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Essay On The Volcano – 10 Lines, Short & Long Essay For Kids

Key Points To Remember When Writing An Essay On The Volcano For Lower Primary Classes

10 lines on the volcano for kids, a paragraph on the volcano for children, short essay on volcano in 200 words for kids, long essay on volcano for children, interesting facts about volcanoes for children, what will your child learn from this essay.

A volcano is a mountain formed through an opening on the Earth’s surface and pushes out lava and rock fragments through that. It is a conical mass that grows large and is found in different sizes. Volcanoes in Hawaiian islands are more than 4000 meters above sea level, and sometimes the total height of a volcano may exceed 9000 meters, depending on the region it is found. Here you will know and learn how to write an essay on a volcano for classes 1, 2 & 3 kids. We will cover writing tips for your essay on a volcano in English and some fun facts about volcanoes in general.

Volcanoes are formed as a result of natural phenomena on the Earth’s surface. There are several types of volcanoes, and each may emit multiple gases. Below are some key points to remember when writing an essay on a volcano:

Start with an introduction about how volcanoes are formed. How they impact the Earth, what they produce, and things to watch out for.
Discuss the different types of volcanoes and talk about the differences between them.
Cover the consequences when volcanoes erupt and the extent of the damage on Earth.
Write a conclusion paragraph for your essay and summarise it.

When writing a few lines on a volcano, it’s crucial to state interesting facts that children will remember. Below are 10 lines on volcanoes for an essay for classes 1 & 2 kids.

Some volcanoes erupt in explosions, and then some release magma quietly.
Lava is hot and molten red in colour and cools down to become black in colour.
Hot gases trapped inside the Earth are released when a volcano erupts.
A circle of volcanoes is referred to as the ‘Ring of Fire.’
Volcano formations are known as seismic activities.
Active volcanoes are spread all across the earth.
Volcanoes can remain inactive for thousands of years and suddenly erupt.
Most volcanic eruptions occur underwater and result from plates diverging from the margins.
Volcanic hazards happen in the form of ashes, lava flows, ballistics, etc.
Volcanic regions have turned into tourist attractions such as the ones in Hawaii.

Volcanoes can be spotted at the meeting points of tectonic plates. Like this, there are tons of interesting facts your kids can learn about volcanoes. Here is a short paragraph on a volcano for children:

A volcano can be defined as an opening in a planet through which lava, gases, and molten rock come out. Earthquake activity around a volcano can give plenty of insight into when it will erupt. The liquid inside a volcano is called magma (lava), which can harden. The Roman word for the volcano is ‘vulcan,’ which means God of Fire. Earth is not the only planet in the solar system with volcanoes; there is one on Mars called the Olympus Mons. There are mainly three types of volcanoes: active, dormant, and extinct. Some eruptions are explosive, and some happen as slow-flowing lava.

Small changes occur in volcanoes, determining if the magma is rising or not flowing enough. One of the common ways to forecast eruptions is by analysing the summit and slopes of these formations. Below is a short essay for classes 1, 2, & 3:

As a student, I have always been curious about volcanoes, and I recently studied a lot about them. Do you know? Krakatoa is a volcano that made an enormous sound when it exploded. Maleo birds seek refuge in the soil found near volcanoes, and they also bury their eggs in these lands as it keeps the eggs warm. Lava salt is a popular condiment used for cooking and extracted from volcanic rocks. And it is famous for its health benefits and is considered superior to other forms of rock or sea salts. Changes in natural gas composition in volcanoes can predict how explosive an eruption can be. A volcano is labelled active if it constantly generates seismic activity and releases magma, and it is considered dormant if it has not exploded for a long time. Gas bubbles can form inside volcanoes and blow up to 1000 times their original size!

Volcanic eruptions can happen through small cracks on the Earth’s surface, fissures, and new landforms. Poisonous gases and debris get mixed with the lava released during these explosions. Here is a long essay for class 3 kids on volcanoes:

Lava can come in different forms, and this is what makes volcanoes unique. Volcanic eruptions can be dangerous and may lead to loss of life, damaging the environment. Lava ejected from a volcano can be fluid, viscous, and may take up different shapes.

When pressure builds up below the Earth’s crust due to natural gases accumulating, that’s when a volcanic explosion happens. Lava and rocks are shot out from the surface to make room on the seafloor. Volcanic eruptions can lead to landslides, ash formations, and lava flows, called natural disasters. Active volcanoes frequently erupt, while the dormant ones are unpredictable. Thousands of years can pass until dormant volcanoes erupt, making their eruption unpredictable. Extinct volcanoes are those that have never erupted in history.

The Earth is not the only planet in the solar system with volcanoes. Many volcanoes exist on several other planets, such as Mars, Venus, etc. Venus is the one planet with the most volcanoes in our solar system. Extremely high temperatures and pressure cause rocks in the volcano to melt and become liquid. This is referred to as magma, and when magma reaches the Earth’s surface, it gets called lava. On Earth, seafloors and common mountains were born from volcanic eruptions in the past.

What Is A Volcano And How Is It Formed?

A volcano is an opening on the Earth’s crust from where molten lava, rocks, and natural gases come out. It is formed when tectonic plates shift or when the ocean plate sinks. Volcano shapes are formed when molten rock, ash, and lava are released from the Earth’s surface and solidify.

Types Of Volcanoes

Given below various types of volcanoes –

1. Shield Volcano

It has gentle sliding slopes and ejects basaltic lava. These are created by the low-viscosity lava eruption that can reach a great distance from a vent.

2. Composite Volcano (Strato)

A composite volcano can stand thousands of meters tall and feature mudflow and pyroclastic deposits.

3. Caldera Volcano

When a volcano explodes and collapses, a large depression is formed, which is called the Caldera.

4. Cinder Cone Volcano

It’s a steep conical hill formed from hardened lava, tephra, and ash deposits.

Causes Of Volcano Eruptions

Following are the most common causes of volcano eruptions:

1. Shifting Of Tectonic Plates

When tectonic plates slide below one another, water is trapped, and pressure builds up by squeezing the plates. This produces enough heat, and gases rise in the chambers, leading to an explosion from underwater to the surface.

2. Environmental Conditions

Sometimes drastic changes in natural environments can lead to volcanoes becoming active again.

3. Natural Phenomena

We all understand that the Earth’s mantle is very hot. So, the rock present in it melts due to high temperature. This thin lava travels to the crust as it can float easily. As the area’s density is compromised, the magma gets to the surface and explodes.

How Does Volcano Affect Human Life?

Active volcanoes threaten human life since they often erupt and affect the environment. It forces people to migrate far away as the amount of heat and poisonous gases it emits cannot be tolerated by humans.

Here are some interesting facts:

The lava is extremely hot!
The liquid inside a volcano is known as magma. The liquid outside is called it is lava.
The largest volcano in the solar system is found on Mars.
Mauna Loa in Hawaii is the largest volcano on Earth.
Volcanoes are found where tectonic plates meet and move.

Your child will learn a lot about how Earth works and why volcanoes are classified as natural disasters, what are their types and how they are formed.

Now that you know enough about volcanoes, you can start writing the essay. For more information on volcanoes, be sure to read and explore more.

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Essays About Volcanoes: Top 5 Examples and 10 Prompts

Do you need to write essays about volcanoes but don’t know where to start? Check out our top essay examples and prompts to help you write a high-quality essay.

Considered the planet’s geologic architects, volcanoes are responsible for more than 80% of the Earth’s surface . The mountains, craters, and fertile soil from these eruptions give way to the very foundation of life itself, making it possible for humans to survive and thrive.

Aside from the numerous ocean floor volcanoes, there are 161 active volcanoes in the US . However, these beautiful and unique landforms can instantly turn into a nightmare, like Mt. Tambora in Indonesia, which killed 92,000 people in 1815 .

Various writings are critical to understanding these openings in the Earth’s crust, especially for students studying volcanoes. It can be tricky to write this topic and will require a lot of research to ensure all the information gathered is accurate.

To help you, read on to see our top essay examples and writing prompts to help you begin writing.

Top 5 Essay Examples

1. short essay on volcanoes by prasad nanda , 2. types of volcanoes by reena a , 3. shield volcano, one of the volcano types by anonymous on gradesfixer.com, 4. benefits and problems caused by volcanoes by anonymous on newyorkessays.com, 5. volcanoes paper by vanessa strickland, 1. volcanoes and their classifications, 2. a dormant volcano’s eruption, 3. volcanic eruptions in the movies, 4. the supervolcano: what is it, 5. the word’s ring of fire, 6. what is a lahar, 7. why does a volcano erupt, 8. my experience with volcanic eruptions, 9. effects of volcanic eruptions, 10. what to do during volcanic disasters.

“The name, “volcano” originates from the name Vulcan, a god of fire in Roman mythology.”

Nanda briefly defines volcanoes, stating they help release hot pressure that builds up deep within the planet. Then, he discusses each volcano classification, including lava and magma’s roles during a volcanic eruption. Besides interesting facts about volcanoes (like the Ojos del Salado as the world’s tallest volcano), Nanda talks about volcanic eruptions’ havoc. However, he also lays down their benefits, such as cooled magma turning to rich soil for crop cultivation.

“The size, style, and frequency of eruptions can differ greatly but all these elements are correlated to the shape of a volcano.”

In this essay, Reena identifies the three main types of volcanoes and compares them by shape, eruption style, and magma type and temperature. A shield volcano is a broad, flat domelike volcano with basaltic magma and gentle eruptions. The strato or composite volcano is the most violent because its explosive eruption results in a lava flow, pyroclastic flows, and lahar. Reena shares that a caldera volcano is rare and has sticky and cool lava, but it’s the most dangerous type. To make it easier for the readers to understand her essay, she adds figures describing the process of volcanic eruptions.

“All in all, shield volcanoes are the nicest of the three but don’t be fooled, it can still do damage.”

As the essay’s title suggests, the author focuses on the most prominent type of volcano with shallow slopes – the shield volcano. Countries like Iceland, New Zealand, and the US have this type of volcano, but it’s usually in the oceans, like the Mauna Loa in the Hawaiian Islands. Also, apart from its shape and magma type, a shield volcano has regular but calmer eruptions until water enters its vents.

“Volcanic eruptions bring both positive and negative impacts to man.”

The essay delves into the different conditions of volcanic eruptions, including their effects on a country and its people. Besides destroying crops, animals, and lives, they damage the economy and environment. However, these misfortunes also leave behind treasures, such as fertile soil from ash, minerals like copper, gold, and silver from magma, and clean and unlimited geothermal energy. After these incidents, a place’s historic eruptions also boost its tourism.

“Beautiful and powerful, awe-inspiring and deadly, they are spectacular reminders of the dynamic forces that shape our planet.”

Strickland’s essay centers on volcanic formations, types, and studies, specifically Krakatoa’s eruption in 1883. She explains that when two plates hit each other, the Earth melts rocks into magma and gases, forming a volcano. Strickland also mentions the pros and cons of living near a volcanic island. For example, even though a tsunami is possible, these islands are rich in marine life, giving fishermen a good living.

Are you looking for more topics like this? Check out our round-up of essay topics about nature .

10 Writing Prompts For Essays About Volcanoes

Do you need more inspiration for your essay? See our best essay prompts about volcanoes below:

Identify and discuss the three classifications of volcanoes according to how often they erupt: active, dormant or inactive, and extinct. Find the similarities and differences of each variety and give examples. At the end of your essay, tell your readers which volcano is the most dangerous and why.

Volcanoes that have not erupted for a very long time are considered inactive or dormant, but they can erupt anytime in the future. For this essay, look for an inactive volcano that suddenly woke up after years of sleeping. Then, find the cause of its sudden eruption and add the extent of its damage. To make your piece more interesting, include an interview with people living near dormant volcanoes and share their thoughts on the possibility of them exploding anytime.

Essays About Volcanoes: Volcanic eruptions in the movies

Choose an on-screen depiction of how volcanoes work, like the documentary “ Krakatoa: Volcano of Destruction .” Next, briefly summarize the movie, then comment on how realistic the film’s effects, scenes, and dialogues are. Finally, conclude your essay by debating the characters’ decisions to save themselves.

The Volcanic Explosivity Index (VEI) criteria interpret danger based on intensity and magnitude. Explain how this scale recognizes a supervolcano. Talk about the world’s supervolcanoes, which are active, dormant, and extinct. Add the latest report on a supervolcano’s eruption and its destruction.

Identify the 15 countries in the Circum-Pacific belt and explore each territory’s risks to being a part of The Ring of Fire. Explain why it’s called The Ring of Fire and write its importance. You can also discuss the most dangerous volcano within the ring.

If talking about volcanoes as a whole seems too generic, focus on one aspect of it. Lahar is a mixture of water, pyroclastic materials, and rocky debris that rapidly flows down from the slopes of a volcano. First, briefly define a lahar in your essay and focus on how it forms. Then, consider its dangers to living things. You should also add lahar warning signs and the best way to escape it.

Use this prompt to learn and write the entire process of a volcanic eruption. Find out the equipment or operations professionals use to detect magma’s movement inside a volcano to signal that it’s about to blow up. Make your essay informative, and use data from reliable sources and documentaries to ensure you only present correct details.

If you don’t have any personal experience with volcanic eruptions, you can interview someone who does. To ensure you can collect all the critical points you need, create a questionnaire beforehand. Take care to ask about their feelings and thoughts on the situation.

Write about the common effects of volcanic eruptions at the beginning of your essay. Next, focus on discussing its psychological effects on the victims, such as those who have lost loved ones, livelihoods, and properties.

Help your readers prepare for disasters in an informative essay. List what should be done before, during, and after a volcanic eruption. Include relevant tips such as being observant to know where possible emergency shelters are. You can also add any assistance offered by the government to support the victims.Here’s a great tip: Proper grammar is critical for your essays. Grammarly is one of our top grammar checkers. Find out why in this Grammarly review .

Maria Caballero is a freelance writer who has been writing since high school. She believes that to be a writer doesn't only refer to excellent syntax and semantics but also knowing how to weave words together to communicate to any reader effectively.

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Essay on Volcano

Students are often asked to write an essay on Volcano in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Volcano

What is a volcano.

A volcano is a crack in the Earth’s surface. Through this crack, melted rock, ash, and gases can escape from deep inside the Earth. Think of it like a soda bottle. If you shake it and then open the top, everything rushes out. That’s similar to what happens during a volcanic eruption.

Types of Volcanoes

There are mainly three types: shield, cone, and composite. Shield volcanoes are broad and flat. Cone volcanoes are steep and pointy. Composite volcanoes are tall and can be very explosive. Each type acts differently when it erupts.

Why Do Volcanoes Erupt?

Deep inside the Earth, it’s so hot that rocks melt into liquid called magma. When magma is lighter than the rock around it, it moves up. If it reaches the Earth’s surface, it erupts. This can happen because of the Earth’s plates moving and creating pressure.

Living with Volcanoes

People live near volcanoes for the fertile soil, which is good for farming. But, living close to a volcano can be dangerous. Scientists help by monitoring volcanoes to predict eruptions and keep people safe.

Also check:

10 Lines on Volcano
Paragraph on Volcano

250 Words Essay on Volcano

A volcano is a crack in the Earth’s surface where molten rock, ash, and gases from deep inside the Earth come out. Think of it like a soda bottle that’s been shaken up. When you open the cap, everything rushes out because of the pressure. In the same way, when a volcano erupts, it releases pressure from beneath the Earth’s crust.

There are different kinds of volcanoes, mainly based on their shape and how often they erupt. Some are called shield volcanoes because they’re broad and low, like a warrior’s shield. Others are called stratovolcanoes, which are tall and steep. They usually have more explosive eruptions. Then there are cinder cone volcanoes, which are smaller and made of bits of rock and ash.

Volcanoes erupt because of the movement of tectonic plates, which are big pieces of the Earth’s surface. When these plates move, they can cause magma from deep inside the Earth to push its way up to the surface. This magma then becomes lava when it comes out of the volcano.

The Impact of Volcanoes

Volcanoes can be dangerous, destroying homes and forests with their lava flows and ash. But they also create new land and bring important nutrients to the soil, which can help plants grow. Plus, the gases they release into the atmosphere can affect the Earth’s climate.

Understanding volcanoes helps us prepare for their eruptions and appreciate the powerful forces that shape our planet.

500 Words Essay on Volcano

Volcanoes: nature’s fiery breath.

Volcanoes are fascinating natural wonders that capture our imaginations. These colossal mountains showcase the immense power of nature, capable of awe-inspiring eruptions and destruction. Let’s explore the world of volcanoes and delve into some of their most intriguing aspects.

A Peek Inside a Volcano

Imagine a giant underground chamber filled with molten rock, known as magma. This magma is incredibly hot, and it’s constantly pushing against the Earth’s crust. When the pressure becomes too intense, it finds a way to escape, and that’s when a volcano erupts.

Types of Volcanic Eruptions

There are various types of volcanic eruptions, each with its own characteristics. Some eruptions are explosive, sending ash and lava soaring high into the air. Others are more gentle, with lava flowing slowly out of the volcano. Some eruptions produce glowing clouds of ash, called pyroclastic flows, which can race down the volcano’s slopes at high speeds.

Volcanic Hazards

While volcanoes can be a sight to behold, they also pose potential hazards. Lava flows can destroy entire villages and forests, and ash clouds can disrupt air travel. Volcanic eruptions can also trigger earthquakes, landslides, and tsunamis.

Predicting Volcanic Eruptions

Scientists are constantly studying volcanoes to better understand their behavior and predict when they might erupt. They use various instruments to monitor seismic activity, gas emissions, and ground deformation. By gathering this data, scientists can often provide warnings before an eruption occurs, giving people time to evacuate.

Volcanoes and the Environment

Volcanic eruptions can have both positive and negative impacts on the environment. On the one hand, they can release harmful gases and ash into the atmosphere, which can affect air quality and climate. On the other hand, volcanic eruptions can create new landforms, provide fertile soil for agriculture, and support unique ecosystems.

Conclusion: The Majestic Force of Nature

Volcanoes are a powerful reminder of the Earth’s dynamic nature. They can be both destructive and awe-inspiring, showcasing the incredible forces that shape our planet. By studying volcanoes, we can better understand the Earth’s processes and prepare for potential hazards, while still appreciating their majestic beauty.

That’s it! I hope the essay helped you.

If you’re looking for more, here are essays on other interesting topics:

Essay on Vitamins
Essay on Visit To A Strange Place
Essay on Visit To A Beach

Apart from these, you can look at all the essays by clicking here .

Happy studying!

Volcanoes, explained

These fiery peaks have belched up molten rock, hot ash, and gas since Earth formed billions of years ago.

Volcanoes are Earth's geologic architects. They've created more than 80 percent of our planet's surface, laying the foundation that has allowed life to thrive. Their explosive force crafts mountains as well as craters. Lava rivers spread into bleak landscapes. But as time ticks by, the elements break down these volcanic rocks, liberating nutrients from their stony prisons and creating remarkably fertile soils that have allowed civilizations to flourish.

There are volcanoes on every continent, even Antarctica. Some 1,500 volcanoes are still considered potentially active around the world today; 161 of those—over 10 percent—sit within the boundaries of the United States .

But each volcano is different. Some burst to life in explosive eruptions, like the 1991 eruption of Mount Pinatubo , and others burp rivers of lava in what's known as an effusive eruption, like the 2018 activity of Hawaii's Kilauea volcano. These differences are all thanks to the chemistry driving the molten activity. Effusive eruptions are more common when the magma is less viscous, or runny, which allows gas to escape and the magma to flow down the volcano's slopes. Explosive eruptions, however, happen when viscous molten rock traps the gasses, building pressure until it violently breaks free.

How do volcanoes form?

The majority of volcanoes in the world form along the boundaries of Earth's tectonic plates—massive expanses of our planet's lithosphere that continually shift, bumping into one another. When tectonic plates collide, one often plunges deep below the other in what's known as a subduction zone .

As the descending landmass sinks deep into the Earth, temperatures and pressures climb, releasing water from the rocks. The water slightly reduces the melting point of the overlying rock, forming magma that can work its way to the surface—the spark of life to reawaken a slumbering volcano.

Not all volcanoes are related to subduction, however. Another way volcanoes can form is what's known as hotspot volcanism. In this situation, a zone of magmatic activity —or a hotspot—in the middle of a tectonic plate can push up through the crust to form a volcano. Although the hotspot itself is thought to be largely stationary, the tectonic plates continue their slow march, building a line of volcanoes or islands on the surface. This mechanism is thought to be behind the Hawaii volcanic chain .

Where are all these volcanoes?

Some 75 percent of the world's active volcanoes are positioned around the ring of fire , a 25,000-mile long, horseshoe-shaped zone that stretches from the southern tip of South America across the West Coast of North America, through the Bering Sea to Japan, and on to New Zealand.

For Hungry Minds

This region is where the edges of the Pacific and Nazca plates butt up against an array of other tectonic plates. Importantly, however, the volcanoes of the ring aren't geologically connected . In other words, a volcanic eruption in Indonesia is not related to one in Alaska, and it could not stir the infamous Yellowstone supervolcano .

What are some of the dangers from a volcano?

Volcanic eruptions pose many dangers aside from lava flows. It's important to heed local authorities' advice during active eruptions and evacuate regions when necessary.

These crystal lava shards are ‘four dimensional videos’ of a volcano’s underworld

Iceland's latest eruption is quieting down—but the explosive upheaval isn't over yet

Scientists found life in a volcano’s ‘lava tubes’—life on other planets could be next

One particular danger is pyroclastic flows, avalanches of hot rocks, ash, and toxic gas that race down slopes at speeds as high as 450 miles an hour . Such an event was responsible for wiping out the people of Pompeii and Herculaneum after Mount Vesuvius erupted in A.D. 79 .

Similarly, volcanic mudflows called lahars can be very destructive. These fast-flowing waves of mud and debris can race down a volcano's flanks, burying entire towns.

Ash is another volcanic danger. Unlike the soft, fluffy bits of charred wood left after a campfire, volcanic ash is made of sharp fragments of rocks and volcanic glass each less than two millimeters across. The ash forms as the gasses within rising magma expand, shattering the cooling rocks as they burst from the volcano's mouth. It's not only dangerous to inhale , it's heavy and builds up quickly. Volcanic ash can collapse weak structures, cause power outages, and is a challenge to shovel away post-eruption.

Can we predict volcanic eruptions?

Volcanoes give some warning of pending eruption, making it vital for scientists to closely monitor any volcanoes near large population centers. Warning signs include small earthquakes, swelling or bulging of the volcano's sides, and increased emission of gasses from its vents. None of those signs necessarily mean an eruption is imminent, but they can help scientists evaluate the state of the volcano when magma is building.

However, it's impossible to say exactly when, or even if, any given volcano will erupt. Volcanoes don't run on a timetable like a train. This means it's impossible for one to be “overdue” for eruption —no matter what news headlines say.

What is the largest eruption in history?

The deadliest eruption in recorded history was the 1815 explosion of Mount Tabora in Indonesia. The blast was one of the most powerful ever documented and created a caldera —essentially a crater—4 miles across and more than 3,600 feet deep. A superheated plume of hot ash and gas shot 28 miles into the sky, producing numerous pyroclastic flows when it collapsed.

The eruption and its immediate dangers killed around 10,000 people. But that wasn't its only impact. The volcanic ash and gas injected into the atmosphere obscured the sun and increased the reflectivity of Earth, cooling its surface and causing what's known as the year without a summer. Starvation and disease during this time killed some 82,000 more people, and the gloomy conditions are often credited as the inspiration for gothic horror tales, such as Mary Shelley's Frankenstein .

Although there have been several big eruptions in recorded history, volcanic eruptions today are no more frequent than there were a decade or even a century ago. At least a dozen volcanoes erupt on any given day. As monitoring capacity for—and interest in—volcanic eruptions increases, coverage of the activity more frequently appears in the news and on social media. As Erik Klemetti, associate professor of geosciences at Denison University, writes in The Washington Post : “The world is not more volcanically active, we’re just more volcanically aware.”

Volcanoes don’t just erupt on schedule—but they have been in Iceland

Why Iceland's latest eruption may be the most dangerous in recent history

Startling volcanic activity has town in Iceland bracing for crisis

A huge volcano near Naples has been convulsing. What does it mean?

Mysteries lurk below Iceland's restless volcanoes

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33 Writing Prompts about Volcanoes

Mount St. Helens blew its top and captured the imagination and fear of Americans everywhere.

Of course, the destruction brought on by Mount St. Helens was nothing compared to the devastation of Krakatoa or the splendor of Vesuvius.

However, apart from being volcanoes, all of these events managed to capture the imagination of everyone who lived on the Earth to see their majesty and might.

Volcanoes still have that power in the classroom, from what students read to making paper mache volcanoes. So, letting them think more deeply upon volcanoes through these prompts will help spark a longer interest for them, as well as inspiring some wonderful writing along the way!

How to Use These Writing Prompts

There are a lot of ways to use these prompts.

You can use them over an extended period of time, or use them all in a day.

They can be used to jump into a discussion or as prompts to get students to think about volcanoes internally.

At any rate, the goal of these prompts is to spark curiosity in volcanoes and help students understand their importance in our lives and on Earth.

After all, volcanoes are responsible from everything from natural disasters to the formation of land as we know it today.

The Writing Prompts About Volcanoes:

Here are thirty-three different writing prompts about volcanoes:

What do you think it’s like to be near an erupting volcano?
Are volcanoes scary? Why or why not?
What are some potential after effects of a volcano?
Is the initial eruption of a volcano worse than the after effects? Why or why not?
What is volcanic rock, and how does it form?
What is the Ring of Fire?
If you could visit one volcano, which would it be?
Would you want to see a volcano erupt in person?
What type of impact do you think volcanic ash can have on the environment?
How do volcanoes form islands?
What are some famous volcanoes that you know? How do you know them?
What does it mean for a volcano to blow its top?
How long have volcanoes existed?
Why are volcanoes important to how the Earth was formed?
Some people think that it was volcanoes, and not a meteor, that killed the dinosaurs. Which do you think killed the dinosaurs? Why?
Hot springs are considered to be a natural wonder that help you relax like a spa. They’re also a sign of a volcano. Would knowing this make it hard for you to relax? Why or why not?
What do you think the worst volcanic eruption in American history is?
What is a super volcano?
Yellowstone National Park is known as one of the most beautiful parks in the world. Underneath it is a super volcano. Would you still want to visit the park? Why or why not?
Do you think any animals can live in a volcano? Which ones?
What does it mean for a volcano to be dormant?
What does it mean for a volcano to be extinct?
Are active volcanoes always dangerous? Why or why not?
A volcanologist is someone who studies volcanoes. Does this sound like an interesting job? Why or why not?
Geologists study rocks and rock formations. How might this intersect with knowledge about volcanoes?
How are volcanoes and earthquakes related?
If you discovered a new volcano, what would you do?
Pompeii was an ancient city that was destroyed by a volcano called Mt. Vesuvius. Today, it’s known for being incredibly well preserved due to the eruption, with people stuck in the middle of their everyday lives. What do you think when the people of Pompeii thought when Mt. Vesuvius erupted?
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Volcanoes and Their Characteristics Essay

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Volcanoes always presented a broad area for researches in terms of their close relationship between their forms, structures, the styles of their eruption, and the mineral composition of their magma and lava. In the following paper, different types of volcanic mountains will be examined and compared in order to make conclusions concerning the relationship between the volcanoes’ structure and their features. Generally, after evaluating data, it appears that depending on the process of volcano formation it may be related to one of the four existing volcano types which are known for their different characteristics and “conduct” while eruptions.

First of all, speaking about different types of volcanoes’ structure, it should be mentioned that depending on their geographic location and, thus, appurtenance to a certain lithosphere platform with varied features, volcanoes demonstrate different ways of eruption ranging from the so-called “quiet” ones to the very disastrous and dangerous (Furniss 56). In general, volcanoes are subdivided into the following categories: shield volcanoes, composite volcanoes, lava domes or plug domes, and, finally, cinder cones which can be distinguished by their sizes, forms, and functioning. All of these volcano types have their peculiarities in structure and way of eruption.

In addition, the very notion of “volcano” is to be explained. A volcano is a geological landform that is made up of two parts – the upper one called a cone, and the lower one called fissure where volcanic material is accumulated (Hess 391). According to Furniss (57),

The vast majority of volcanoes are found along the boundaries of tectonic plates. Convergent boundaries, where the plates are crashing into each other, host around 90 percent of what we generally think of as volcanoes. Here, as one plate is pushed below another–a process is known as subduction–it melts, the resultant magma rising and causing volcanic eruptions. Volcanoes also form away from plate boundaries, above so-called volcanic hotspots.

Volcanoes are known for their disastrous nature which many times led to serious tragedies for humanity. During volcanoes’ eruptions, numerous developing processes in the crust of the earth are taking place. According to Furniss (58),

Several factors are used to assign eruptions a score, including the volume of erupted material, the height of the eruption column, and the duration. The index ranges between zero and eight, with each increase in score representing a ten-fold increase in the various factors. The highest score on the list, VEI8, is reserved for eruptions that emit more than 1,000 cubic kilometers of material.

Below, all the four types of volcanoes will be addressed along with their features and popularities.

Discussing shield volcanoes, it should be said that they are formed as a result of a huge amount of free lava spilling from a vent and coming up abundantly and widely; gradually congealing lava forms a low and wide mountain of dome shape which is called a shield volcano. These types of volcanoes can be very high. Among them are popular volcanoes in Hawaii.

With regards to composite volcanoes, it should be stated that they are formed as a result of the eruption of both lava and tephra which occurs from a central vent. At the end of the erupting process lava and tephra form a cone in the shape of a tower which is called a composite volcano. These volcanoes tend to develop into mountains of beautiful and symmetrical forms. Among the most famous volcanoes of this type are Mount Fuji in Japan and Mount Rainer in Washington (Hegner 88).

Addressing plug domes, it should be stated that they are formed as a result of congealing of very viscous lava (for example, rhyolite one) which is too thick to flow at a remote distance. As a result of this process, the mountain grows from below and from within. This mountain is called a plug dome. The volcanoes of this type are rather young and can be found in numerous parts of the earth including Mono Lake in California.

And finally, speaking about cinder cones, it should be stated that they are formed as a result of tephra’s building up. A cone-shaped mountain that is the result of this process is called a cinder cone volcano. These volcanic mountains are the smallest ones of all types and are generally less in their size than 500 meters. An example of such a volcanic mountain is SP Mountain situated in Arizona, and belonging to the Colorado Plato.

Concluding on all the information related above, it should be stated that there exists a close connection between the structure of any particular volcano and the style of its functioning and its magma and lava nature. Evaluating a row of facts about the functioning of different types of volcanoes, it appears that depending on the process of volcano formation it may be related to one of the four existing volcano types which are known for their different characteristics and “conduct”. In general, volcanoes are subdivided into the following categories: shield volcanoes, composite volcanoes, lava domes or plug domes, and, finally, cinder cones.

Furniss, Charlie. “Volcanoes: They’re the Most Powerful Expressions of Nature’s Might, Responsible for Mass Extinctions, Global Climate Change, and the Demise of Entire Civilisations, but How Much Do We Really Know About Volcanoes? and Just How Close Are We to the Holy Grail of Accurately Predicting When They’re Going to Explode?.” Geographical Mar. 2007: 52+. Questia . Web.

Hegner, E., et al. “Testing Tectonic Models with Geochemical Provenance Parameters in Greywacke.” Journal of the Geological Society (2005): 87+. Questia . Web.

Hess, Darrel. Physical Geography Laboratory Manual (10th ed.), The United States: Prentice-Hall, 2010. Print.

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Home — Essay Samples — Environment — Natural Disasters — The Environmental Effects of Volcanoes: A Comprehensive Analysis

The Environmental Effects of Volcanoes: a Comprehensive Analysis

Categories: Natural Disasters

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Published: Mar 6, 2024

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Air pollution and climate change, positive effects of volcanic activity, mitigating the environmental impacts of volcanoes.

The release of gases and particulate matter into the atmosphere
Global cooling caused by volcanic ash blocking out sunlight
Contribution to air pollution and respiratory problems
Impact on climate change through the release of carbon dioxide
Creation of new landmasses supporting new ecosystems
Increased biodiversity on newly formed landmasses
Contribution to the formation of mineral deposits
Use of volcanic ash and rocks for various purposes
Close monitoring of volcanic activity to predict eruptions
Development of effective mitigation strategies
Reducing reliance on fossil fuels and supporting renewable energy sources
Protection of vulnerable ecosystems and biodiversity

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ENCYCLOPEDIC ENTRY

A volcano is an opening in a planet or moon’s crust through which molten rock and gases trapped under the surface erupt, often forming a hill or mountain.

Volcanic eruption

Volcanic eruptions can create colorful and dramatic displays, such as this eruption of this volcano in the Virunga Moutains of the Democratic Republic of the Congo.

Photograph by Chris Johns

A volcano is an opening in a planet or moon’s crust through which molten rock, hot gases, and other materials erupt . Volcanoes often form a hill or mountain as layers of rock and ash build up from repeated eruptions .

Volcanoes are classified as active, dormant, or extinct. Active volcanoes have a recent history of eruptions ; they are likely to erupt again. Dormant volcanoes have not erupted for a very long time but may erupt at a future time. Extinct volcanoes are not expected to erupt in the future.

Inside an active volcano is a chamber in which molten rock, called magma , collects. Pressure builds up inside the magma chamber, causing the magma to move through channels in the rock and escape onto the planet’s surface. Once it flows onto the surface the magma is known as lava .

Some volcanic eruptions are explosive, while others occur as a slow lava flow. Eruptions can occur through a main opening at the top of the volcano or through vents that form on the sides. The rate and intensity of eruptions, as well as the composition of the magma, determine the shape of the volcano.

Volcanoes are found on both land and the ocean floor. When volcanoes erupt on the ocean floor, they often create underwater mountains and mountain ranges as the released lava cools and hardens. Volcanoes on the ocean floor become islands when the mountains become so large they rise above the surface of the ocean.

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Essay on volcanoes | geology.

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After reading this article you will learn about:- 1. Introduction to Volcanoes 2. Volcano Formation 3. Volcanic Landforms 4. Major Gases Emitted by Volcanoes 5. Lightning and Whirlwinds 6. Features Produced by the Escape of Gases from Volcanic Lavas 7. Volcanic Products 8. Source of the Explosive Energy 9. Classification of Pyroclastics 10. Lahars-Mudflows on Active and Inactive Cones and Other Details.

Essay Contents:

Essay on the Volcanoes and Atmospheric Pollution

Essay # 1. Introduction to Volcanoes :

A volcano is a cone shaped hill or mountain which is built-up around an opening in the earth’s surface through which hot gases, rock fragments and lavas are ejected.

Due to the accumulation of the solid fragments around the conduit a conical mass is built which increases in size to become a large volcanic mountain. The conical mass so built-up is called a volcano. However the term volcano is taken to include not only the central vent in the earth but also the mountain or hill built around it.

Volcanoes are in varying sizes, varying from small conical hills to loftiest mountains on the earth’s surface. The volcanoes of the Hawaiian Islands are nearly 4300 metres above sea level since they are built over the floor of the Pacific ocean which at the site is 4300 to 5500 metres deep, the total height of the volcano may be about 9000 m or more.

The very high peaks in the Andes, in the Cascade Range of the Western United States, Mt. Baker, Mt. Adams, Mt. Hood etc. are all volcanoes which have now become extinct. Over 8000 independent eruptions have been identified from earth’s volcanoes. There are many inaccessible regions and ocean floors where volcanoes have occurred undocumented or unnoticed.

The eruption of a volcano is generally preceded by earthquakes and by loud rumblings like thunder which may continue on a very high scale during the eruption. The loud rumblings are due to explosive movement of gases and molten rock which are held under very high pressure. Before eruption of a volcano fissures are likely to be opened, nearby lakes likely to be drained and hot springs may appear at places.

The eruptive activity of volcanoes is mostly named after the well-known volcanoes, which are known for particular type of behaviour, like Strambolian, Vulcanian, Vesuvian, Hawaiian types of eruption. Volcanoes may erupt in one distinct way or may erupt in many ways, but, the reality is, these eruptions provide a magical view inside the earth’s molten interior.

The nature of a volcanic eruption is determined largely by the type of materials ejected from the vent of the volcano. Volcanic eruptions may be effusive (fluid lavas) or dangerous and explosive with blasts of rock, gas, ash and other pyroclasts.

Some volcanoes erupt for just a few minutes while some volcanoes spew their products for a decade or more. Between these two main types viz. effusive and explosive eruptions, there are many subdivisions like, eruption of gases mixed with gritty pulverised rock forming tall dark ash clouds seen for many kilometres, flank fissure eruptions with lava oozing from long horizontal cracks on the side of a volcano.

There is also the ground hugging lethally hot avalanches of volcanic debris called pyroclastic flows. When magma rises, it may encounter groundwater causing enormous phreatic, i.e., steam eruptions. Eruptions may also release suffocating gases into the atmosphere. Eruptions may produce tsunamis and floods and may trigger earthquakes. They may unleash ravaging rockslides and mudflows.

Volcanoes which have had no eruptions during historic times, but may still show fairly fresh signs of activity and have been active in geologically recent times are said to be dormant. There are also volcanoes which were formerly active but are of declining activity a few of which may be emitting only steam and other gases.

Geysers are hot springs from which water is expelled vigorously at intervals and are characteristics of regions of declining volcanic activity. Geysers are situated in Iceland, the Yellowstone park in USA and in New Zealand.

In contrast to the explosive type of volcanoes, there exist eruptions of great lava flows quietly pouring out of fissures developed on the earth’s surface. These eruptions are not accompanied by explosive outbursts. These are fissure eruptions.

Ex: Deccan Trap formations in India. The lavas in these cases are mostly readily mobile and flow over low slopes. The individual flows are seldom over a few meters in thickness; the average thickness may be less than 15 meters. If the fissure eruptions have taken place in valleys however, the thickness may be much greater.

A noteworthy type of volcano is part of the world encircling mid-ocean ridge (MOR) visible in Iceland. The MOR is really a single, extremely long, active, linear volcano, connecting all spreading plate boundaries through all oceans. Along its length small, separate volcanoes occur. The MOR exudes low-silica, highly fluid basalt producing the entire ocean floor and constituting the largest single structure on the face of the earth.

Essay # 2. Location of Volcanoes:

Volcanoes are widely distributed over the earth, but they are more abundant in certain belts. One such belt encircles the Pacific ocean and includes many of the islands in it. Other volcanic areas are the island of West Indies, those of the West coast of Africa, the Mediterranean region and Iceland.

Most volcanoes occur around or near the margins of the continents and so these areas re regarded as weak zones of the earth’s crust where lavas can readily work their way upward. There are over 400 active volcanoes and many more inactive ones. Numerous submarine volcanoes also exist.

Since it is not possible to examine the magma reservoir which fees a volcano our information must be obtained by studying the material ejected by the volcano. This material consists of three kinds of products, viz. liquid lava, fragmented pyroclasts and gases. There may exist a special problem in studying the gases, both in collecting them under hazardous conditions or impossible conditions.

It may also be difficult to ascertain that the gases collected are true volcanic gases and are not contaminated with atmospheric gases. Investigation of the composition of extruded rock leads to a general, although not very detailed, correlation between composition and intensity of volcanic eruption.

In general, the quite eruptions are characteristic of those volcanoes which emit basic or basaltic lavas, whereas the violent eruptions are characteristic of volcanoes emitting more silicic rocks.

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Essay # 3 . formation of volcanoes :.

The term volcano is used to mean both the opening in the earth’s crust, i.e. the vent through which the eruption of magma occurs as well as the hill built- up by the erupted material. Volcanoes occur where the cracks in the earth’s crust lead to the magma chamber.

The liquid magma which is lighter than the surrounding rocks is under high pressure is pushed up towards the surface through these cracks. In this process the gases dissolved in the magma which expand are released providing an upward push to the magma.

As the magma gets closer to the surface, due to the reducing confining pressure to overcome, the magma and the gases flow faster. The magma, depending on its viscosity may quietly pour to the surface in the form of a flood of molten rock or it may explosively spurt out the molten rock to considerable heights as showers on the surrounding region with solid rock fragments and globs of molten rock. The liquid magma discharged to the surface is called lava.

Essay # 4 . Volcanic Landforms :

Many surface features of volcanic origin are created. These features range from towering peaks and huge lava sheets to small and low craters. The features created by a volcano vary depending on the type of eruption, the material erupted and the effects of erosion.

Four types of volcanic landforms are formed:

i. Ash and Cinder Cones or Explosion Cones:

These appear where explosive eruptions take place. When very hot solid fragments from a central crater (or a subsidiary crater) are ejected. A concave cone of height not exceeding 300 m is formed.

ii. Lava Cones:

These are formed from slowly upwelling lava.

These are of two types:

(a) Steep Sided Volcanoes:

These are formed from sticky acid lava which gets hardened quickly. The highly viscous lava which is squeezed out makes spines like tower.

(b) Shield Volcanoes:

These show gently sloping dome features. These are formed from runny lava which flows long distances, before getting hardened.

iii. Composite Cones or Strato-Volcanoes or Strato Cones:

These volcanoes have concave cone shaped sides of alternating ash and lava layers. These are common in most very high volcanoes. In some cases solid lava may plug the main pipe to the crater. Then pent up gases may blast the top off.

When the magma chamber empties, the summit of the volcano collapses. As a consequence, the feature produced is a vast shallow cavity called a Caldera. Strato volcanoes are the accumulated products of many volcanoes. Chemically most of these products are andesite. Some are dacite and a few are basalt and rhyolite. Due to this chemical mix and characteristic interlayering of lava flows, this volcano is called strato volcano.

iv. Shield Volcanoes:

When a volcano vent produces many successive basaltic lava flows stacked one on top of another in eruptive order, the resulting landform is called a shield volcano. A cinder cone and its associated lava flow can be thought of as the initial building blocks of a shield volcano.

A cinder cone is monogenetic because it forms from a single short-lived eruption (of a few years to a decade or two in duration). In contrast, a shield volcano that is an accumulation of the products of many eruptions over a period of say thousands to hundreds of thousands of years is polygenic.

On land these volcanoes have low angle cones. When they form under water they start with a steeper shape because the lava freezes much faster and does not travel far. The shape fattens to the shield form as the cone builds above the sea level.

v. Plateau Basalts or Lava Plains:

These form the bulk of many volcanic fields. These are features which occur where successive flows of basic lava leaks through fissures, over land surface and then cools and hardens forming a blanket-like feature.

The surface appearance of a flow provides information on the composition and temperature of the magma before it solidified. Very hot low viscosity basalt flows far and fast and produces smooth ropy surfaces. Cooler and less-fluid basalt flows form irregular, jagged surfaces littered with blocks.

The lava flows have blanketed to about 2000 m thickness covering 6,50,000 sq.km. in the Indian Deccan Plateau. Such lava flows have also created the U.S. Columbia River Plateau, the Abyssinian Plateau, the Panama Plateau of South America and the Antrim Plateau of Northern Ireland.

Magmas like dacite and rhyolite that have high silica contents are cooler and more viscous than basalt and hence they do not flow far resulting in the features, lobes, pancakes and domes. Domes often plug up the vent from which they issued, sometimes creating catastrophic explosions and may create a crater.

Eroded volcanoes have their importance. They give us a glimpse of the interior plumbing along which the magma rose to the surface. At the end of an eruption, magma solidifies in the conduits along which it had been rising. The rock so formed is more resistant than the shattered rock forming the walls and hence these lava filled conduits are often left behind when the rest of the volcano has been eroded away.

The filling of the central vertical vent is somewhat circular in section and forms a spire called a neck. The filling of cracks along which lava rose forms nearly vertical tabular bodies called dikes. Sometimes magma works its way along cracks that are nearly horizontal, often along bedding planes of sedimentary rocks. This results in the formation of table-like bodies called sills.

Essay # 5 . Major Gases Emitted by Volcanoes :

Volcanic gases present within the magma are released as they reach the earth’s surface, escaping at the major volcanic opening or from fissures and vents along the side of the volcano. The most prevalent gases emitted are steam, carbon dioxide and hydrogen sulphide. Carbon dioxide is an invisible, odourless poisonous gas. The table below shows the gases emitted from volcanoes.

Essay # 6 . Lightning and Whirlwinds :

Lightning flashes accompany most volcanic eruptions, especially those involving dust. The cause of this lightning is believed to be either contact of sea water with magma or generation of static electricity by friction between colliding particles carried in the erupting gases. Lightning is characteristic of vulcanian eruptions and is common during glowing avalanches.

Whirlwinds are seen during many volcanic eruptions. They are seen above hot lavas. Sometimes they form inverted cones extending a little below the eruption cloud. Energy for the whirlwinds might be from the hot gases and lava, high velocity gas jets in the eruption, heat released into the atmosphere during falls of hot tephra or where lava flows into the sea creating steam.

Essay # 7 . Features Produced by the Escape of Gases from Volcanic Lavas :

The gases of volcanic lavas produce several interesting features while they escape. They expand in the lava of the flow and thus cause the formation of Scoriaceous and Pumiceous rocks. By their explosion, they blow the hardened lava above them in the conduit, into bits and thus produce pyroclastic material.

They form clouds above volcanoes, the rain from which assists in the production of mud flows. When the volcano becomes inactive, they escape aiding in the formation of jumaroles, geysers and hot springs. Scoriaceous rocks are extremely porous. They are formed by the expansion of the steam and other gases beneath the hardened crust of a lava. The final escape of the gases from the hardening lava leaves large rounded holes in the rock.

Pumice is a rock also formed by the expansion and escape of gases. In pumice, many of the holes are in the form of long, minute, closed tubes which make the rock so light that it will float on water.

These tubes are formed by the expansive force of large amounts of gases in an extremely viscous lava that cools very rapidly, forming a glassy rock. Pumice is the rock that is usually formed from the lava ejected from explosive volcanoes. It can be blown to kilometres by explosions.

Essay # 8 . Volcanic Products :

Volcanoes give out products in all the states of matter – gases, liquids and solids.

Steam, hydrogen, sulphur and carbon dioxide are discharged as gases by a volcano. The steam let out by a volcano condenses in the air forming clouds which shed heavy rains. Various gases interact and intensify the heat of the erupting lavas. Explosive eruptions cause burning clouds of gas with scraps of glowing lava called nuees ardentes.

The main volcanic product is liquid lava. Sticky acid lava on cooling, solidifies and hardens before flowing long distances. Such lava can also block a vent resulting in pressure build-up which was relieved by an explosion. Basic fluid lava of lesser viscosity flows to great distances before hardening.

Some lava forms are produced by varying conditions as follows. Clinkery block shaped features are produced when gas spurted from sluggish molten rock capped by cooling crust. These are called Aa.

Pahoehoe is a feature which has a wrinkled skin appearance caused by molten lava flowing below it.

Pillow lava is a feature resembling pillows. This feature piles up when fast cooling lava erupts under water.

Products in explosive outbursts are called Pyroclasts. These consist of either fresh material or ejected scraps of old hard lava and other rock. Volcanic bombs include pancake-flat scoria shaped on impacting the ground and spindle bombs which are twisted at ends as they whizzle through the air. Acid lava full of gas formed cavities produces a light volcanic rock.

Pumice which is so light it can float on water. The product Ignimbrite shows welded glassy fragments. Lapilli are hurled out cinder fragments. Vast clouds of dust or very tiny lava particles are called volcanic ash. Volcanic ash mixed with heavy rain creates mudflows.

Sometimes mudflows can bury large areas of land. Powerful explosions can smoother land for many kilometres around with ash and can hurl huge amount of dust into the higher atmosphere. Violent explosions destroy farms and towns, but volcanic ash provides rich soil for crops.

i. Hot springs:

The underground hot rocks heat the spring waters creating hot springs. The hot springs shed minerals dissolved in them resulting in crusts of calcium carbonate and quartz (geyserite).

ii. Smoker:

This is a submarine hot spring at an oceanic spreading ridge. This submarine spring emits sulphides and builds smoky clouds.

iii. Geyser:

Periodically steam and hot water are forced up from a vent by super-heated water in pipe like passage deep down. Famous geysers are present in Iceland and Yellowstone National Park.

iv. Mud volcano:

This is a low mud cone deposited by mud-rich water gushing out of a vent.

v. Solfatara:

This is a volcanic vent which emits steam and sulphurous gas.

vi. Fumarole:

This is a vent which emits steam jets as at Mt. Etna, Sicily and Valley of Ten Thousand smokes in Alaska.

vii. Mofette:

This is a small vent which emits gases including carbon dioxide. These occur in France, Italy and Java.

Various terms used while describing volcanic features are given below:

i. Magma Chamber:

Magma is created below the surface of the earth (at depth of about 60 km) and is held in the magma chamber until sufficient pressure is built-up to push the magma towards the surface.

This is a pipe like passage through which the magma is pushed up from the magma chamber.

This is the outlet end of the pipe. Magma exits out of the vent. If a vent erupts only gases, it is called fumarole.

iv. Crater:

Generally the vent opens out to a depression called crater at the top of the volcano. This is caused due to the collapse of the surface materials.

v. Caldera:

This is a very big crater formed when the top of an entire volcanic hill collapses inward.

When the erupted materials cover the vent, a volcanic dome is created covering the vent. Later as the pressure of gas and magma rises, another eruption occurs shattering the dome.

A mountain-like structure created over thousands of years as the volcanic lava, ash, rock fragments are poured out onto the surface. This feature is called volcanic cone.

viii. Pyroclastic Flow :

A pyroclastic flow (also known as nuee ardentes (French word) is a ground hugging, turbulent avalanche of hot ash. pumice, rock fragments, crystals, glass shards and volcanic gas. These flows can rush down the steep slopes of a volcano at 80 to 160 km/li, burning everything in their path.

Temperatures of these flows can reach over 500°C. A deposit of this mixture is also often referred to as pyroclastic flow. An even more energetic and dilute mixture of searing volcanic gases and rock-fragments is called a pyroclastic surge which can easily ride up and over ridges.

ix. Seamounts :

A spectacular underwater volcanic feature is a huge localized volcano called a seamount. These isolated underwater volcanic mountains rise from 900 m to 3000 m above the ocean floor, but typically are not high enough to poke above the water surface.

Seamounts are present in all the oceans of the world, with the Pacific ocean having the highest concentration. More than 2000 seamounts have been identified in this ocean. The Gulf of Alaska also has many seamounts. The Axial Seamount is an active volcano off the north coast of Oregon (currently rises about 1400 m above the ocean floor, but its peak is still about 1200 m below the water surface.

Essay # 9 . Source of the Explosive Energy :

The energy for the explosive violence comes from the expansion of the volatile constituents present in the magma, the gas content of which determines the degree of commination of the materials and the explosive violence of the eruption.

This energy is expanded in two ways, firstly in the expulsion of the materials into the atmosphere and secondly, due to expansion within the magma leading to the development of vesicles. The most important gas is steam, which may form between 60 to 90 per cent of the total gas content in a lava. Carbon dioxide, nitrogen and sulphur dioxide occur commonly and hydrogen, carbon monoxide, sulphur and chlorine are also present.

Essay # 10 . Classification of Pyroclastics :

Pyroclastics refer to fragmental material erupted by a volcano. The larger fragments consisting of pieces of crystal layers beneath the volcano or of older lavas broken from the walls of the conduit or from the surface of the crater are called blocks.

Volcanic bombs are masses of new lava blown from the crater and solidified during flight, becoming round or spindle shaped as they are hurled through the air. They may range in size from small pellets up to huge masses weighing many kilonewtons.

Sometimes they are still plastic when they strike the surface and are flattened or distorted as they roll down the side of the cone. Another type called bread crust bomb resembles a loaf of bread with large gaping cracks in the crust.

This cracking of the crust results from the continued expansion of the internal gases. Many fragments of lava and scoria solidified in flight drop back into the crater and are intermixed with the fluid lava and are again erupted.

In contrast to bombs, smaller broken fragments are lapilli (from Italian meaning, little stones) about the size of walnuts; then in decreasing size, cinders, ash and dust. The cinders and ash are pulverized lava, broken up by the force of rapidly expanding gases in them or by the grinding together of the fragments in the crater, as they are repeatedly blown out and dropped back into the crater after each explosion.

Pumice is a type of pyroclastic produced by acidic lavas if the gas content is so great as to cause the magma to froth as it rises in the chimney of the volcano. When the expansion occurs the rock from the froth is expelled as pumice. Pumice is of size ranging from the size of a marble to 30 cm or more in diameter. Pumice will float in water due to many air spaces formed by the expanding gases.

Lava fountains in which steam jets blow the lava into the air produce a material known as Pele’s hair which is identical with rock wool which is manufactured by blowing a jet of steam into a stream of molten rock (Rock wool is used for many types of insulation).

Coarse angular fragments become cemented to form a rock called volcanic breccia. The finer material like cinders and ash forms thick deposits which get consolidated through the percolation of ground water and is called tuff. Tuff is a building stone used in the volcanic regions. It is soft and easily quarried and can be shaped and has enough strength to be set into walls with mortar.

i. Agglomerate:

The debris in and around the vent contains the largest ejected masses of lava bombs which are embedded in dust and ash. A deposit of this kind is known as agglomerate. The layers of ash and dust which are formed for some distance around the volcano and which builds its cone, become hardened into rocks which are called tuffs.

Ash includes all materials with size less than 4 mm. It is pulverized lava, in which the fragments are often sharply angular and formed of volcanic glass; these angular and often curved fragments are called shards.

Since the gas content of ash on expulsion is high it has considerable mobility on reaching the surface; it is also hot and plastic, the result of these conditions being that the fragments often become welded together. The finest of ash is so light that wind can transport it for great distances.

The table below sets out a general classification of pyroclastic rocks based on the particle size of the fragments forming the rocks.

The chart in Fig. 15.3 summarizes the names of the common magmas and their associated ranges in silica. A very important property of magma that determines the eruption style and the eventual shape of the volcano it builds, is its resistance to flow, namely its viscosity.

Magma viscosity increases as its silica content increases. Eruptions of highly viscous magmas are violent. The highly viscous rhyolite magma piles up its ticky masses right over its eruptive vent to farm tall steep sided volcanoes.

On the contrary the basaltic magma flows great distances from its eruptive vent to from low, broad volcanic features. Magma in the intermediate viscosity spectrum say the andesite magma tends to form volcanoes of profile shapes between these two extremes.

An additional important ingredient of magma is water. Magmas also contain carbon dioxide and various sulphur-containing gases in solution. These substances are considered volatile since they tend to occur as gases at temperatures and pressures at the surface of the earth.

As basaltic magma changes composition toward rhyolite the volatiles become concentrated in the silica-rich magma. Presence of these volatiles (mainly water) in high concentration produces highly explosive volcanoes. It should be noted that these volatiles are held in magma by confining pressure. Within the earth, the confining pressure is provided by the load of the overlying rocks.

As the magma rises from the mantle to depths about 1.5 km or somewhat less, the rock load is reduced to that extent that the volatiles (mainly water) start to boil. Bubbles rising through highly viscous rhyolitic magma have such difficulty to escape their way, that many carry blobs of magma and fine bits of rock with them and they finally break free and jet violently upward resulting in a violent buoyant eruption column that can rise to kilometres above the earth.

The fine volcanic debris in such a powerful eruption gets dispersed within the upper atmosphere, hide the sunlight affecting the weather. The greater the original gas concentration in a magma and the greater the volume rate of magma leaving the vent, the taller is the eruption column produced.

The gases escaping from magma during eruption mix with the atmosphere and become part of the air humans, animals and plants breath and assimilate. However as magma cools and solidifies to rock during eruption, some of the gas remains trapped in bubbles creating vesicles. Generally all volcanic rocks contain some gas bubbles. A variety of vesicular rhyolite is pumice. Pumice is vesicular to such an extent, it floats in water.

Essay # 15. Classification of Volcanic Activity:

A classification of volcanic activity based on the type of product is shown in Fig. 15.4. The basic subdivision is based on the proportions of the gas, liquid and solid components, which can be represented on a triangular diagram. The four basic triangles represent the domain of four basic kinds of volcanic activity.

Essay # 16. Cone Topped and Flat Topped Volcanoes:

Generally rhyolite volcanoes are flat-topped because rhyolite magma which is extremely viscous, oozes out of the ground, piles up around the vent and then oozes away a bit to form a pancake shape. In contrast basalt volcanoes generally feed lava flows that flow far from the vent, building a cone.

Basaltic tephra (large particles of different size) is a spongy-looking black, rough material of pebble or cobble. Commercially this tephra is known as cinder and is used for gardening and rail-road beds. In some situations basaltic volcanoes develop flat top profile.

Flat topped volcanoes of basalt can form when there is an eruption under a glacier. Instead of getting ejected as tephra to form a cone, it forms a cauldron of lava surrounded by ice and water and eventually solidifying. When the ice melts, a steep-sided, table-shaped mountain known as a tuya remains. Volcanoes of this type are common in Iceland and British Columbia, where volcanoes have repeatedly erupted under glaciers.

Surprisingly, the Pacific ocean is a home to many flat-topped undersea basaltic mountains. These are called seamounts. How these seamounts were formed was a mystery for a long time. Surveying and dredging operations revealed that most seamounts were formerly conical volcanoes projecting above the water.

Geologists found that the conical volcanoes got lowered due to subsidence and the tops of the volcanoes came near the sea water level and the powerful waves mowed them flat. Continued subsidence caused them to drop below the water surface.

Essay # 17. Types of Volcanoes :

There are many types of volcanoes depending on the composition of magma especially on the relative proportion of water and silica contents. If the magma contains little of either of these, it is more liquid and it flows freely forming a shallow rounded hill.

Large water content with little silica permits the vapour to rapidly rise through the molten rock, throwing fountains of fire high into the air. More silica and less water in the magma make the magma more viscous. Such magma flows slowly and builds-up a high dome.

High content of both water and silica create another condition. In such a case the dense silica prevents the water from vaporizing until it is close to the surface and results in a highly explosive way. Such an eruption is called a Vulcan eruption.

Other types of eruption are named after people or regions associated with them. Vesuvian eruption named after Vesuvius is a highly explosive type occurring after a long period of dormancy. This type ejects a huge column of ash and rock to great heights upto 50 km.

A peleean eruption named after the eruption of Mt. Pelee in Martin que in 1902 is a highly violent eruption ejecting a hot cloud of ash mixed with considerable quantity of gas which flows down the sides of the volcano like a liquid. The cloud is termed nuee ardente meaning glowing cloud. Pyroclastic or ash flow refers to a flow of ash, solid rock pieces and gas. Hawaiian eruptions eject fire fountains.

Essay # 18. Violence of Volcanic Eruptions :

Volcanic activity may be classified by its violence, which in turn is generally related to rock type, the course of eruptive activity and the resulting landforms. We may in general distinguish between lava eruptions associated with basic and intermediate magmas and pumice eruptions associated with acid magmas.

The percentage of the fragmentary material in the total volcanic material produced can be used as a measure of explosiveness and if calculated for a volcanic region can be adopted as an Explosion Index (E), useful for comparing one volcanic region with others. Explosion Index for selected volcanic regions by Rittmann (1962) are shown in the table below.

Newhall and Self (1982) proposed a Volcanic Explosivity Index (VEI) which helps to summarize many aspects of eruption and is shown in the table below.

Essay # 19. Famous Volcanoes around the World :

Many volcanoes are present around the world. Some of the largest and well known volcanoes are listed in the table below.

Essay # 20. Volcanic Hazards :

Volcanic eruptions have caused destruction to life and property. In most cases volcanic hazards cannot be controlled, but their impacts can be mitigated by effective prediction methods.

Flows of lava, pyroclastic activity, emissions of gas and volcanic seismicity are major hazards. These are accompanied with movement of magma and eruptive products of the volcano. There are also other secondary effects of the eruptions which may have long term effects.

In most cases volcanoes let out lava which causes property damage rather than injuries or deaths. For instance, in Hawaii lava flows erupted from Kilauea for over a decade and as a consequence, homes, roads, forests, cars and other vehicles were buried in lavas and in some cases were burned by the resulting fires but no lives were lost. Sometimes it has become possible to control or divert the lava flow by constructing retaining walls or by some provision to chill the front of the lava flow with water.

Lava flows move slowly. But the pyroclastic flows move rapidly and these with lateral blasts may kill lives before they can run away. In 1902, on the island of Martinique the most destructive pyroclastic flow of the century occurred resulting in very large number of deaths.

A glowing avalanche rushed out of the flanks of Mount Pelee, running at a speed of over 160 km/h and killed about 29000 people. In A.D. 79 a large number of people of Pompeii and Herculaneum were buried under the hot pyroclastic material erupted by Mount Vesuvius.

The poisonous gas killed many of the victims and their bodies got later buried by pyroclastic material. In 1986, the eruption of the volcano at Lake Nyos, Cameroon killed over 1700 people and over 3000 cattle.

When magma moves towards the surface of the earth rocks may get fractured and this may result in swarms of earthquakes. The turbulent bubbling and boiling of magma below the earth can produce high frequency seismicity called volcanic tremor.

There are also secondary and tertiary hazards connected with volcanic eruptions. A powerful eruption in a coastal setting can cause a displacement of the seafloor leading to a tsunami. Hazardous effects are caused by pyroclastic material after a volcanic eruption has ceased.

Either melt water from snow or rain at the summit of the volcano can mix with the volcanic ash and start a deadly mud flow (called as lahar). Sometimes a volcanic debris avalanche in which various materials like pyroclastic matter, mud, shattered trees etc. is set out causing damage.

Volcanic eruptions produce other effects too. They can permanently change a landscape. They can block river channels causing flooding and diversion of water flow. Mountain terrains can be severely changed.

Volcanic eruptions can change the chemistry of the atmosphere. The effects of eruption on the atmosphere are precipitation of salty toxic or acidic matter. Spectacular sun set, extended period of darkness and stratospheric ozone depletion are all other effects of eruptions. Blockage of solar radiation by fine pyroclastic material can cause global cooling.

Apart from the above negative effects of volcanisms there are a few positive effects too. Periodic volcanic eruptions replenish the mineral contents of soils making it fertile. Geothermal energy is provided by volcanism. Volcanism is also linked with some type of mineral deposits. Magnificent scenery is provided by some volcanoes.

The study of volcanoes has great scientific as well as social interest. Widespread tephra layers inter-bedded with natural and artificial deposits have been used for deciphering and dating glacial and volcanic sequences, geomorphic features and archeological sites.

For example, ash from Mt. St. Helens Volcano in Washington travelled at least 900 km into Alberta. North American Indians fashioned tools and weapons out of volcanic glass, the origin of which is used to trace migratory and trading routes.

Volcanoes are windows through which the scientists look into the interiors of the earth. From volcanoes we learn the composition of the earth at great depths below the surface. We learn about the history of shifting layers of the earth’s crust. We learn about the processes which transform molten material into solid rock.

From the geological historical view point, volcanic activity was crucial in providing to the earth a unique habitat for life. The degassing of molten materials provided water for the oceans and gases for the atmosphere – indeed, the very ingredients for life and its sustenance.

Essay # 21. Volcanoes and Atmospheric Pollution :

During eruptions volcanoes inject solid particles and gases into the atmosphere. Particles may remain in the atmosphere for months to years and rain back on to the earth. Volcanoes also release chlorine and carbon dioxide.

The main products injected into the atmosphere from volcanic eruptions however are volcanic ash particles and small drops of sulphuric acid in the form of a fine spray known as aerosol. Most chlorine released from volcanoes is in the form of hydrochloric acid which is washed out in the troposphere. Volcanoes also emit carbon dioxide.

During the times of giant volcanic eruptions in the past the amount of carbon dioxide released may have been enough to affect the climate. In general global temperatures are cooler for a year or two after a major eruption.

A large magnitude pyroclastic eruption such as a caldera-forming event can be expected to eject huge volumes of fine ash high into the atmosphere where it may remain for several years, carried around the globe by strong air currents in the upper atmosphere.

The presence of this ash will increase the opacity of the atmosphere, that is, it will reduce the amount of sunlight reaching the earth’s surface. Accordingly, the earth’s surface and climate will become cooler. Various other atmospheric effects may be observed. Particularly noticeable is an increase in the intensity of sunsets.

i. Global Warming :

Besides blocking the rays of the sun, the vast clouds of dust and ash that result from a volcanic eruption can also trap ultraviolet radiation within the atmosphere causing global warming.

Volcanic eruptions usually include emissions of gases such as carbon dioxide which can further enhance this warming. Even if it lasted only for a relatively short time, a sudden increase in temperature could in turn have contributed to extinctions by creating an environment unsuitable for many animals.

ii. Geothermal Energy :

Geothermal energy is the heat energy trapped below the surface of the earth. In all volcanic regions, even thousands of years after activity has ceased the magma continues to cool at a slow rate. The temperature increases with depth below the surface of the earth. The average temperature gradient in the outer crust is about 0.56° C per 30 m of depth.

There are regions however, where the temperature gradient may be as much as 100 times the normal. This high heat flow is often sufficient to affect shallow strata containing water. When the water is so heated such surface manifestations like hot springs, fumaroles, geysers and related phenomena often occur.

It may be noted that over 10 per cent of the earth’s surface manifests very high heat flow and the hot springs and related features which are present in such areas have been used throughout the ages, for bathing, laundry and cooking.

In some places elaborate health spas and recreation areas have been developed around the hot-spring areas. The cooling of magma, even though it is relatively close to the surface is such a slow process that probably in terms of human history, it may be considered to supply a source of heat indefinitely.

Temperatures in the earth rise with increasing depth at about 0.56°C per 30 m depth. Thus if a well is drilled at a place where the average surface temperature is say 15.6°C a temperature of 100°C would be expected at about 4500 m depth. Many wells are drilled in excess of 6000 m and temperatures far above the boiling point of water are encountered.

Thermal energy is stored both in the solid rocks and in water and steam filling the pore spaces and fractures. The water and steam serve to transmit the heat from the rocks to a well and then to the surface.

In a geothermal system water also serves as the medium by which heat is transmitted from a deep igneous source to a geothermal reservoir at a depth shallow enough to be tapped by drilling. Geothermal reservoirs are located in the upward flowing part of a water – convective system. Rainwater percolates underground and reaches a depth where it is heated as it comes into contact with the hot rocks.

On getting heated, the water expands and moves upward in a convective system. If this upward movement is unrestricted the water will be dissipated at the surface as hot springs; but if such upward movement is prevented, trapped by an impervious layer the geothermal energy accumulates, and becomes a geothermal reservoir.

Until recently it was believed that the water in a geothermal system was derived mainly from water given off by the cooling of magma below the surface. Later studies have revealed that most of the water is from surface precipitation, with not more than 5 per cent from the cooling magma.

Production of electric power is the most important application of geothermal energy. A geothermal plant can provide a cheap and reliable supply of electrical energy. Geothermal power is nearly pollution free and there is little resource depletion.

Geothermal power is a significant source of electricity in New Zealand and has been furnishing electricity to parts of Italy. Geothermal installations at the Geysers in northern California have a capacity of 550 megawatts, enough to supply the power needs of the city of San Francisco.

Geothermal energy is versatile. It is being used for domestic heating in Italy, New Zealand and Iceland. Over 70 per cent of Iceland’s population live in houses heated by geothermal energy. Geothermal energy is being used for forced raising of vegetables and flowers in green houses in Iceland where the climate is too harsh to support normal growth. It is used for animal husbandry in Hungary and feeding in Iceland.

Geothermal energy can be used for simple heating processes, drying or distillation in every conceivable fashion, refrigeration, tempering in various mining and metal handling operations, sugar processing, production of boric acid, recovery of salts from seawater, pulp and paper production and wood processing.

Geothermal desalinization of sea water holds promise for abundant supply of fresh water. In some areas it is a real alternative to fossil fuels and hydroelectricity and in future may help meet the crisis of our insatiable appetite for energy.

iii. Phenomena Associated with Volcanism :

In some regions of current or past volcanic activity some phenomena related to volcanism are found. Fumaroles, hot springs and geysers are the widely known belonging to this group. During the process of consolidation of molten magma either at the surface or at some depths beneath the surface gaseous emanations may be given off.

These gas vents constitute the fumaroles. The Valley of Ten Thousand Smokes in Alaska is a well-known fumarole and is maintained as a national monument. This group of fumaroles was formed by the eruption of Mount Katmai in 1912. This valley of area of about 130 square kilometres contains thousands of vents discharging steam and gases.

These gases are of varied temperatures and the temperatures vary from that of ordinary steam to superheated steam coming out as dry gas. Many of the gases escaping from the vents may be poisonous, such as hydrogen sulphide and carbon monoxide which are suffocating and may settle at low places in the topography. For example, the fumaroles at the Poison Valley, Java discharge deadly poisonous gases.

Solfataras are fumaroles emitting sulphur gases. At some places, the hydrogen sulphide gases undergo oxidation on exposure to air to form sulphur. The sulphur accumulates in large amount so that the rocks close to the solfataras may contain commercial quantities of sulphur.

Hot springs are also phenomena associated with volcanic activity. Waters from the surface which penetrate into the ground can get heated either by contact with the rocks which are still hot or by gaseous emanations from the volcanic rocks. The water so heated may re-emerge at the surface giving rise to hot springs. In some situations the hot springs may be intermittently eruptive. Such intermittently hot springs are called geysers.

Lava: Types and Eruptions | Volcanoes
Submarine and Sub Glacial Eruptions | Volcanoes

Science , Essay , Geology , Volcanoes , Essay on Volcanoes

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Volcanic Eruptions and Their Repose, Unrest, Precursors, and Timing (2017)

Chapter: summary.

Volcanoes are a key part of the Earth system, and open a window into the inner workings of the planet. More than a dozen volcanoes are usually erupting on Earth at any given time. Some of these eruptions are devastating, killing people, damaging homes and infrastructure, altering landscapes, and even disrupting climate. Fortunately, many eruptions are preceded by signs of unrest (precursors) that can be used to anticipate eruptions and support disaster planning.

Accurate forecasts of the likelihood and magnitude of an eruption in a specified timeframe are rooted in a scientific understanding of the processes that govern the storage, ascent, and eruption of magma. Yet our understanding of volcanic systems is incomplete and biased by the limited number of volcanoes and eruption styles observed with advanced instrumentation. Eruption behaviors are diverse (e.g., violently explosive or gently effusive, intermittent or sustained, last hours or decades) and may change over time at a volcano. More accurate and societally useful forecasts of eruptions and their hazards are possible by using new observations and models of volcanic processes.

At the request of managers at the National Aeronautics and Space Administration, the National Science Foundation (NSF), and the U.S. Geological Survey (USGS), the National Academies of Sciences, Engineering, and Medicine established a committee to undertake the following tasks:

Summarize current understanding of how magma is stored, ascends, and erupts.
Discuss new disciplinary and interdisciplinary research on volcanic processes and precursors that could lead to forecasts of the type, size, and timing of volcanic eruptions.
Describe new observations or instrument deployment strategies that could improve quantification of volcanic eruption processes and precursors.
Identify priority research and observations needed to improve understanding of volcanic eruptions and to inform monitoring and early warning efforts.

These four tasks are closely related. Improved understanding of volcanic processes guides monitoring efforts and improves forecasts. In turn, improved monitoring provides the insights and constraints to better understand volcanic processes. This report identifies key science questions, research and observation priorities, and approaches for building a volcano science community capable of tackling them. The discussion below first summarizes common themes among these science questions and priorities, and then describes ambitious goals (grand challenges) for making major advances in volcano science.

KEY QUESTIONS AND RESEARCH AND OBSERVATION PRIORITIES

Many fundamental aspects of volcanoes are understood conceptually and often quantitatively. Plate tectonics and mantle convection explain where volcanoes occur. We understand how magma is initially created in Earth’s mantle, how it rises toward the surface, that it can be stored and evolve in magma chambers within the crust, and that a number of processes initiate eruptions. We understand in general terms why some magmas erupt explosively and others do not, and why some volcanoes erupt more often than others. High-resolution observations and models combined provide a detailed and quantitative picture of eruptions once they begin.

Our understanding is incomplete, however, especially those aspects of volcano behavior that define the timing, duration, style, size, and consequences of eruptions. Additional questions relate to our ability to forecast eruptions. What processes produce commonly observed geophysical and geochemical precursors? What factors determine if and when unrest will be followed by eruption? How rapidly do magmas mobilize prior to eruption? Which volcanoes are most likely to erupt in coming years and decades? And we are only beginning to decipher the impacts of large volcanic eruptions on Earth’s climate and biosphere.

Our understanding of the entire life cycle and diversity of volcanoes—from their conception in the mantle to their periods of repose, unrest, and eruption to their eventual demise—is poised for major advances over the next decades. Exciting advances in our ability to observe volcanoes—including satellite measurements of ground deformation and gas emissions, drone observations, advanced seismic monitoring, and real-time, high-speed acquisition of data during eruptions—await broad application to volcanic systems. Parallel advances in analytical capabilities to decipher the history of magmas, and in conceptual, experimental, and numerical models of magmatic and volcanic phenomena, both below and above ground, will provide new insights on the processes that govern the generation and eruption of magma and greatly improve the quality of short-term, months to minutes, forecasts. The time is ripe to test these models with observations from new instrumentation, data collected on fine temporal and spatial scales, and multidisciplinary synthesis.

Four common themes emerged from the research priorities detailed in the following chapters:

Develop multiscale models that capture critical processes, feedbacks, and thresholds to advance understanding of volcanic processes and the consequences of eruptions on Earth systems.

Advances will come from measurements of physical and chemical properties of magmas and erupted materials, deciphering the history of magmas (before and during eruption) recorded in their crystals and bubbles, and developing new models that account for the numerous interacting processes and vast range of scales, from microscopic ash particles and crystals, to eruption columns that extend to the stratosphere.

Collect high-resolution measurements at more volcanoes and throughout their life cycle to overcome observational bias.

Few volcanoes have a long record of monitoring data. New and expanded networks of ground, submarine, airborne, and satellite sensors that characterize deformation, gases, and fluids are needed to document volcanic processes during decade-long periods of repose and unrest. High-rate, near-real-time measurements are needed to capture eruptions as they occur, and efficient dissemination of information is needed to formulate a response. Both rapid response and sustained monitoring are required to document the life cycle of volcanoes. Monitoring and understanding volcanic processes go hand-in-hand: Different types of volcanoes have different life cycles and behaviors, and hence merit different monitoring strategies.

Synthesize a broad range of observations, from the subsurface to space, to interpret unrest and forecast eruption size, style, and duration.

Physics-based models promise to improve forecasts by assimilating monitoring data and observations. Progress in forecasting also requires theoretical and experimental advances in understanding eruption processes, characterization of the thermal and mechanical properties of magmas and their host rocks, and model validation and verification. Critical to eruption forecast-

ing is reproducing with models and documenting with measurements the emergent precursory phenomena in the run-up to eruption.

Obtain better chronologies and rates of volcanic processes.

Long-term forecasts rely on understanding the geologic record of eruptions preserved in volcanic deposits on land, in marine and lake sediments, and in ice cores. Secondary hazards that are not part of the eruption itself, such as mud flows and floods, need to be better studied, as they can have more devastating consequences than the eruption. Understanding the effects of eruptions on other Earth systems, including climate, the oceans, and landscapes, will take coordinated efforts across disciplines. Progress in long-term forecasts, years to decades, requires open-access databases that document the full life cycle of volcanoes.

GRAND CHALLENGES

The key science questions, research and observation priorities, and new approaches highlighted in this report can be summarized by three overarching grand challenges. These challenges are grand because they are large in scope and would substantially advance the field, and they are challenges because great effort will be needed. Figure S.1 illustrates these challenges using the example of the 2016 eruption of Pavlof volcano, Alaska. The volcanic hazards and eruption history of Pavlof are summarized by Waythomas et al. (2006) .

A principal goal of volcano science is to reduce the adverse impacts of volcanism on humanity, which requires accurate forecasts. Most current eruption forecasts use pattern recognition in monitoring and geologic data. Such approaches have led to notable forecasts in some cases, but their use is limited because volcanoes evolve over time, there is a great diversity of volcano behavior, and we have no experience with many of the potentially most dangerous volcanoes. A major challenge is to develop forecasting models based instead on physical and chemical processes, informed by monitoring. This approach is used in weather forecasting. Addressing this challenge requires an understanding of the basic processes of magma storage and ascent as well as thresholds of eruption initiation. This understanding and new discoveries will emerge from new observations, experimental measurements, and modeling approaches. Models are important because they capture our conceptual and quantitative understanding. Experiments test our understanding. Relating models to observations requires multiple types of complementary data collected over an extended period of time.

Determining the life cycle of volcanoes is key for interpreting precursors and unrest, revealing the processes that govern the initiation and duration of eruptions, and understanding how volcanoes evolve between eruptions. Our understanding is biased by an emphasis over the last few decades of observation with modern instruments, and most of these well-studied eruptions have been small events that may not scale to the largest and most devastating eruptions. Strategic deployment of instruments on volcanoes with different characteristics would help build the requisite knowledge and confidence to make useful forecasts. For every volcano in the United States, a realistic goal is to have at least one seismometer to record the small earthquakes that accompany magma movement. Even in the United States, less than half of potentially active volcanoes have a seismometer, and less than 2 percent have continuous gas measurements. Global and daily satellite images of deformation, and the ability to measure passive CO 2 degassing from space would fill critical observational gaps. Geologic and geophysical studies are required to extend understanding of the life cycle of volcanoes to longer periods of time. On shorter time scales, satellite measurements, emerging technologies such as drones, and expansion of ground-based monitoring networks promise to document processes that remain poorly understood.

The volcano science community needs to be prepared to capitalize on the data and insights gained from eruptions as they happen. This will come from effective integration of the complementary research and monitoring roles by universities, the USGS, and other government agencies. Volcano science is fundamentally interdisciplinary and the necessary expertise is spread across these institutions. The science is also international, because every volcano provides insights on processes that drive eruptions. Volcanic eruptions can have global impacts and so demand international collaboration and cooperation. New vehicles are needed to support interdisciplinary research and training, including community collaboration and education at all levels. Examples of similar successful programs in other fields include NSF’s Cooperative Studies of the Earth’s Deep Interior program for interdisciplinary research and National Earthquake Hazards Reduction

Program for federal government agency–academic partnerships.

Results of the above investments in science will be most evident to the public in improved planning and warning and, ideally, a deeper appreciation of this amazing natural phenomenon.

Volcanic eruptions are common, with more than 50 volcanic eruptions in the United States alone in the past 31 years. These eruptions can have devastating economic and social consequences, even at great distances from the volcano. Fortunately many eruptions are preceded by unrest that can be detected using ground, airborne, and spaceborne instruments. Data from these instruments, combined with basic understanding of how volcanoes work, form the basis for forecasting eruptions—where, when, how big, how long, and the consequences.

Accurate forecasts of the likelihood and magnitude of an eruption in a specified timeframe are rooted in a scientific understanding of the processes that govern the storage, ascent, and eruption of magma. Yet our understanding of volcanic systems is incomplete and biased by the limited number of volcanoes and eruption styles observed with advanced instrumentation. Volcanic Eruptions and Their Repose, Unrest, Precursors, and Timing identifies key science questions, research and observation priorities, and approaches for building a volcano science community capable of tackling them. This report presents goals for making major advances in volcano science.

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Science News Explores

Explainer: the volcano basics.

All volcanoes are not alike, but all do deserve respect

An ash burst coming from Washington’s Mount St. Helens in May 1982.

Lyn Topinka/ USGS

Where do volcanoes form?

Volcanoes can form on land or below the sea. Indeed, Earth’s biggest volcano lies submerged a mile below the ocean’s surface. Certain spots on our planet’s surface are especially susceptible to volcano formation.

Most volcanoes, for instance, form at or near the edges — or boundaries — of Earth’s tectonic plates . These plates are large slabs of crust that jostle and scrape past each other. Their movement is driven largely by the circulation of the scalding, liquid rock in Earth’s mantle. That mantle is thousands of kilometers (miles) thick. It lies between our planet’s outer crust and its molten outer core.

The edge of one tectonic plate may begin sliding beneath a neighboring one. This process is known as subduction . The downward-moving plate carries rock back toward the mantle, where temperatures and pressures are very high. This disappearing, water-filled rock melts easily.

Because the liquid rock is lighter than the surrounding material, it will try to float back up toward Earth’s surface. When it finds a weak spot, it breaks through. This creates a new volcano.

Many of the world’s active volcanoes reside along an arc. Known as the “Ring of Fire,” this arc surrounds the Pacific Ocean. (In fact, it was the fiery lava erupting from volcanoes all along this boundary that inspired the arc’s nickname.) Along almost all sections of the Ring of Fire, a tectonic plate is shoving beneath its neighbor.

Many more of the world’s volcanoes, especially those located far from the edge of any plate, develop over or near broad plumes of molten material that rise up from Earth’s outer core. These are called “mantle plumes.” They behave very much like the blobs of hot material in a “lava lamp.” (Those blobs rise from the heat source at the bottom of the lamp. When they cool, they fall back towards the bottom.)

Many oceanic islands are volcanoes. The Hawaiian Islands formed over one well-known mantle plume. As the Pacific plate gradually moved northwest over that plume, a series of new volcanoes punched their way through to the surface. This created the island chain. Today, that mantle plume fuels volcanic activity on the island of Hawaii. It’s the youngest island in the chain.

A small fraction of the world’s volcanoes form where Earth’s crust is being stretched apart, as it is in East Africa. Tanzania’s Mount Kilimanjaro is a prime example. In these thin spots, molten rock can break through to the surface and erupt. The lava they exude can build, layer upon layer, to create tall peaks.

How deadly are volcanoes?

Throughout recorded history, volcanoes have probably killed about 275,000 people, according to a 2001 study led by researchers at the Smithsonian Institution in Washington, D.C. Scientists estimate that almost 80,000 of the deaths — not quite one in every three — were caused by pyroclastic flows . These hot clouds of ash and rock sweep down a volcano’s slopes at hurricane speeds. Volcano-triggered tsunamis likely triggered another 55,000 deaths. These big waves can pose a threat to people living along coasts even hundreds of kilometers (miles) from the volcanic activity.

Many volcano-related deaths happen in the first 24 hours of an eruption. But a surprisingly high fraction — about two in every three — occurs more than a month after an eruption begins. These victims may succumb to indirect effects. Such effects might include famines when crops fail. Or people may return to a danger zone and then die in landslides or during follow-up eruptions.

Each of the past three centuries has seen a doubling of fatal volcanic eruptions. But volcanic activity has remained roughly constant during recent centuries. This suggests, the scientists say, that much of the increase in fatalities is due to population growth or to the decision of people to live (and play) near (or on) volcanoes.

For instance, nearly 50 hikers died on September 27, 2014, while climbing Japan’s Mount Ontake. The volcano unexpectedly erupted . Some 200 other hikers escaped to safety.

How big can a volcanic eruption be?

Some volcanic eruptions amount to small, relatively harmless puffs of steam and ash. At the other extreme are cataclysmic events. These can last for days to months, changing climate across the globe.

Early in the 1980s, researchers invented a scale to describe the strength of a volcanic eruption. This scale, which runs from 0 to 8, is called the Volcanic Explosivity Index (VEI). Each eruption gets a number based on the amount of ash spewed, the height of the ash plume and the power of the eruption.

For each number between 2 and 8, an increase of 1 corresponds to an eruption that’s ten times more powerful. For example, a VEI-2 eruption releases at least 1 million cubic meters (35 million cubic feet) of ash and lava. So a VEI-3 eruption releases at least 10 million cubic meters of material.

Small eruptions pose a threat only to nearby regions. Small clouds of ash might wipe out a few farms and buildings on the slopes of a volcano or on the surrounding plains. They also might smother crops or grazing areas. That could trigger a local famine.

Larger eruptions pose different types of hazards. Their ash can spew dozens of kilometers from the peak. If the volcano is topped with snow or ice, lava flows can melt it. That can create a thick mix of mud, ash, soil and rocks. Called a lahar, this material has a consistency like wet, newly mixed concrete. It can flow far from the peak — and destroy anything in its path.

Nevado del Ruiz is a volcano in the South American nation of Colombia. Its eruption in 1985 created lahars that destroyed 5,000 homes and killed more than 23,000 people. The lahars’ effects were felt in towns up to 50 kilometers (31 miles) from the volcano.

A volcano’s threats can even extend into the sky. Ash plumes can reach altitudes at which jets fly. If ash (which actually is tiny bits of broken rock) gets sucked into an aircraft’s engine, high temperatures there can re-melt the ash. Those droplets can then solidify when they hit the engine’s turbine blades.

This will disrupt the flow of air around those blades, causing the engines to fail. (That’s not something anyone would like to experience when they are several kilometers in the air!) What’s more, flying into a cloud of ash at cruising speed can effectively sandblast a plane’s front windows to the point that pilots can no longer see through them.

Finally, a really big eruption can affect global climate. In a very explosive eruption, particles of ash can reach altitudes above where rains are available to quickly wash them from the air. Now, these ash bits can spread around the world, diminishing how much sunlight reaches Earth’s surface. This will cool temperatures globally, sometimes for many months.

Besides spewing ash, volcanoes also emit a witches’ brew of noxious gases, including carbon dioxide and sulfur dioxide. When sulfur dioxide reacts with the water vapor spewed by eruptions, it creates droplets of sulfuric acid. And if those droplets make it to high altitude, they too can scatter sunlight back into space, cooling climate even more.

It’s happened.

In 1600, for instance, a little-known volcano in the South American nation of Peru erupted. Its ash plumes cooled global climate so much that many parts of Europe had record-setting snowfalls the next winter. Large portions of Europe also suffered unprecedented floods the next spring (when the snow melted). Heavy rains and cool temperatures during the summer of 1601 ensured massive crop failures in Russia. The famines that followed lasted through 1603.

In the end, this one eruption’s impacts resulted in the deaths of an estimated 2 million people — many of them half a world away. (Scientists didn’t make the connection between the Peruvian eruption and the Russian famines until several years after the 2001 study that estimated the death tolls from all volcanoes in recorded history.)

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WATCH — Volcano erupts in Iceland. Here’s how volcanoes work

There are more than 1,500 active volcanoes worldwide, according to researchers

Imagine a stream of lava as tall as a 15-storey building shooting into the sky.

That’s what it looked like when a volcano started erupting in southwestern Iceland on Wednesday.

It was the fifth time this volcano had erupted since December.

Officials evacuated people living in the coastal town of Grindavik.

Volcanic eruptions are common in Iceland, so the people there have experience dealing with them.

But why do volcanoes erupt at all?

Learn more about how volcanoes work by watching the video below. ⬇️⬇️⬇️

How many volcanoes are there.

There are more than 1,500 active volcanoes worldwide, according to the British Geological Survey.

A volcano is called “active” if scientists believe it could erupt in the future.

People stand in the distance against an orange sky filled with clouds.

About 50 to 70 volcanoes erupt per year, according to the British Geological Survey.

Some parts of the world, such as Iceland, are prone to volcanic activity.

The last time a volcano erupted in Canada was about 150 years ago, at Lava Forks, in British Columbia. That’s according to Natural Resources Canada.

It’s in the Pacific “Ring of Fire,” an area in Western Canada known for volcanic activity.

When will this Canadian volcano erupt?

There have been at least 49 volcanic eruptions in British Columbia and the Yukon in the last 10,000 years, according to Natural Resources Canada.

How to stay safe if a volcano erupts

Volcanic eruptions can cause fires and put ash and toxic gases in the air, making it hard to breathe.

Even hundreds of kilometres away, a volcanic eruption can ground airplanes because of ash and smoke.

If you are in an area near an erupting volcano, it’s important to follow local guidelines.

Volcano erupts in Tonga, smoke visible from space

Stay up to date on evacuation orders and leave if you are ordered to do so.

To stay safe from ash indoors, close all windows, doors and fireplaces and turn off all fans, heating and air conditioning systems.

If you are outdoors during an eruption, seek shelter indoors.

If you have to go outside while there is ash falling, wear protective clothing, including long sleeves, goggles and a disposable particulate respirator (like an N95 face mask).

Check out these other extreme nature videos next:

WATCH — Unravelling the cool science behind the polar vortex
WATCH — How hurricanes happen and how to prepare
WATCH — Tornadoes explained: How they form and what to look out for

Have more questions? Want to tell us how we're doing? Use the “send us feedback” link below. ⬇️⬇️⬇️

TOP IMAGE CREDIT: Sophia Groves/Getty Images, graphic design by Philip Street

Rivers of Lava on Venus Reveal a More Volcanically Active Planet

New software let scientists re-examine old radar images, providing some of the strongest evidence yet that volcanoes continue to reshape the hellish planet.

By Robin George Andrews

Witnessing the blood-red fires of a volcanic eruption on Earth is memorable. But to see molten rock bleed out of a volcano on a different planet would be extraordinary. That is close to what scientists have spotted on Venus: two vast, sinuous lava flows oozing from two different corners of Earth’s planetary neighbor.

“After you see something like this, the first reaction is ‘wow,’” said Davide Sulcanese , a doctoral student at the Università d’Annunzio in Pescara, Italy, and an author of a study reporting the discovery in the journal Nature Astronomy , published on Monday.

Earth and Venus were forged at the same time. Both are made of the same primeval matter, and both are the same age and size. So why is Earth a paradise overflowing with water and life, while Venus is a scorched hellscape with acidic skies?

Volcanic eruptions tinker with planetary atmospheres. One theory holds that, eons ago, several apocalyptic eruptions set off a runaway greenhouse effect on Venus, turning it from a temperate, waterlogged world into an arid desert of burned glass.

To better understand its volcanism, scientists hoped to catch a Venusian eruption in the act. But although the planet is known to be smothered in volcanoes, an opaque atmosphere has prevented anyone from seeing an eruption the way spacecraft have spotted them on Io, the hypervolcanic moon of Jupiter .

In the 1990s, NASA’s spacecraft Magellan used cloud-penetrating radar to survey most of the planet. But back then, the relatively low-resolution images made spotting fresh molten rock a troublesome task.

By using modern software to peruse Magellan’s data, scientists have now found two unambiguous lava flows: one tripping down the flank of Sif Mons, a broad shield volcano, and another winding its way across a western part of Niobe Planitia, a flat plain pockmarked with numerous volcanic mountains.

Many planetary scientists reckoned Venus was effervescing with eruptions. “But it’s one thing to strongly suspect it and quite another to know it,” said Paul Byrne , a planetary scientist at Washington University in St. Louis who was not part of the new study.

Venus lacks the plate tectonics of Earth. But its similarly rocky constitution and comparable size suggests that something must still be cooking inside the sun’s second planet — and it should be volcanically active.

There is indirect supporting evidence: Volcanic gases linger in Venus’s skies, and the way that parts of the planet glow suggests they were painted over by lava in the recent geologic past .

Direct evidence of volcanic fury finally, and surprisingly, emerged in 2023, when researchers caught sight of a volcanic vent doubling in size and possibly filling with lava in old Magellan data. Other scientists still yearned for signs of an unequivocal lava flow, an almost literal smoking gun.

Mr. Sulcanese granted their wish. He found bright, riverlike patches on Sif Mons and Niobe Planitia in later Magellan survey images that weren’t present in earlier data. After carefully ruling out other possibilities, including landslides, his team concluded that lava was the only reasonable explanation.

“Magellan is the gift that keeps on giving,” said Stephen Kane , a planetary astrophysicist at the University of California, Riverside, who was not involved with the new study.

Both lava flows are comparable in size to the output of the Kilauea volcano in Hawaii during its three-month paroxysm in 2018. And using these two eruptions, the study’s authors estimate that there is considerably more eruptive activity than previously assumed — and that it’s happening elsewhere on the planet in the present day.

“Venus is active,” said Giuseppe Mitri , an astronomer also at the Università d’Annunzio and an author of the study.

More important, volcanically speaking, Venus “is Earth-like,” said Anna Gülcher , a planetary scientist at the California Institute of Technology who was not involved with the work.

The result also complicates the tentative detection of phosphine in Venus’s atmosphere; phosphine is a substance that is usually associated on Earth with living things. But other explanations for its possible presence on Venus couldn’t be ruled out . Volcanic activity can also make phosphine, but rebuttals to that idea have suggested that Venus simply doesn’t have sufficient volcanism to make it.

“Well, apparently there is,” Dr. Kane said.

The only way to find better answers — on phosphine, Venus’s volcanic cadence, its cataclysmic transformation — is to revisit the planet. Fortunately, a fleet of new spacecraft is set to do just that in the 2030s .

While we wait, Magellan’s memories will continue to offer unexpected gifts.

“We can start to think of Venus as a living, breathing world,” Dr. Byrne said.

What’s Up in Space and Astronomy

Keep track of things going on in our solar system and all around the universe..

Never miss an eclipse, a meteor shower, a rocket launch or any other 2024 event that’s out of this world with our space and astronomy calendar .

Euclid, a European Space Agency telescope launched into space last summer, finally showed off what it’s capable of with a batch of breathtaking images and early science results.

A dramatic blast from the sun set off the highest-level geomagnetic storm in Earth’s atmosphere, making the northern lights visible around the world .

With the help of Google Cloud, scientists who hunt killer asteroids churned through hundreds of thousands of images of the night sky to reveal 27,500 overlooked space rocks in the solar system .

A celestial image, an Impressionistic swirl of color in the center of the Milky Way, represents a first step toward understanding the role of magnetic fields in the cycle of stellar death and rebirth.

Is Pluto a planet? And what is a planet, anyway? Test your knowledge here .

Watch our Memorial Day tribute to the military who sacrificed all to serve their country

Memorial Day is the unofficial start of summer. It's a time to gather with friends and family for a grill out, a picnic, or maybe a trip to the beach to soak up the sun. But while it may well feel like a day of celebration, what sometimes gets forgotten is that it was conceived as a day of commemoration for the brave military members who died serving their country.

A University of Phoenix survey found that less than half of Americans polled knew the exact purpose of Memorial Day, while around a third were unsure of the difference between Memorial Day and Veterans Day.

To clarify, Veterans Day, which takes place in November, is a tribute to all those who served honorably in the military in wartime or peacetime, whether living or dead.

The confusion is compounded by Armed Forces Day, a military celebration held in May for those currently serving. However, while the reasons differ, the sentiment of each day is the same: all three are important opportunities to show gratitude.

So, when you chow down on that hot dog, barrel down that slip 'n slide, or whatever you do for fun this Memorial Day, spare a moment to acknowledge the people in uniform whose sacrifice made a difference.

On this Memorial Day, watch the video for a surprise reunion of battle buddies bonded by the loss of their leade r

Humankind is your go-to spot for good news! Click here to submit your uplifting, cute, or inspiring video moments for us to feature. Also, click here to subscribe to our newsletter , bringing our top stories of the week straight to your inbox.

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When Should You Start Writing Your College Essay?

Posted on May 29, 2024

Let’s be frank: there’s never an ideal moment to craft college essays. At best, there are times that are somewhat less unfavorable.

Why is that? Simply put, there’s constantly going to be something else that requires your attention right now. A more captivating event, a task that eats up more time, a thrilling experience, pressure-filled situations — you get what I mean.

Nevertheless, it’s important to tackle the task of writing your college essays, and it’s best to do so well in advance of submission dates. My extensive experience with a diverse range of students has taught me that composing an essay becomes much more manageable when divided into more digestible segments. Thus, beginning the process early, approaching it gradually, and allowing ample time for introspection and idea generation are crucial steps.

For those seeking additional support or guidance throughout the essay writing process, considering the assistance of professional essay writing services can provide valuable expertise and assistance in crafting compelling and polished essays.

When should I start writing my college essay ?

For every student, it’s best to begin thinking about essay topics early, for example, around winter during your junior year. The most challenging aspect of essay writing for college applications is identifying what to write about, as it requires extensive self-examination and time. Consequently, if your school assigns the task of composing the personal statement (also recognized as the Common App essay) in the spring, you’ll be well-prepared to tackle it.

In most cases, the best time to write my college essay is the summer following the junior year. You should aim to complete it before the senior year kicks off. By doing so, you can remove the burden of essay writing from your to-do list and concentrate on finalizing your application submissions, as well as dedicating attention to your final-year courses and extracurricular engagements.

Students planning to attend summer camp should aim to complete their personal statements before going there. Additionally, they should have all additional essays finished by October 31st.

Students aiming for Early Action or Early Decision should aim to have their essays completed by the end of September, which is a month prior to the typical ED/EA application deadlines. Doing this will ensure you have ample opportunity to review your essay and refine it if necessary before sending in your application in early to mid-October.

Students who have numerous supplement essays should aim to complete them by October 31st. It will allow you to concentrate on your senior year, where maintaining high grades is crucial, and also have ample time to respond to any potential deferrals or waitlist decisions.

When to write college essay depends on your goals and commitments other than applying for college. Yet, it is best for all students to complete their essays at least a month prior to the due date. Doing so allows ample opportunity to carefully review them, make adjustments, and refine the work without the stress of an approaching deadline.

Who can help me in crafting college application essays?

Your mentors, teachers, tutors, and professional admission essay writers can all help you maximize your chances for success. They can oversee your writing process and ensure you meet your deadlines, removing that burden from parents. Additionally, they motivate you to engage in self-reflection about your personal narratives and offer constructive criticism for every version of every essay and application. Essay writers can help you with the entire writing process, ensuring you get a well-crafted and polished essay to submit.

Reach out for help early, during your junior year in November, with the winter months being the preferable period to initiate the writing process. This gives you the necessary time to brainstorm ideas and approach the task in a thoughtful and organized manner.

Final Thoughts

Starting your college essay early is key to creating a compelling and thoughtful piece. By beginning the process during the junior year and aiming to finish by the start of senior year, students can alleviate the pressure of deadlines and dedicate the necessary time to refine their essays. Remember, the support of mentors and professional essay writers can be invaluable in navigating this crucial step towards your college journey, ensuring your essays are both profound and polished.

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COMMENTS

Essay On The Volcano
Here is a short paragraph on a volcano for children: A volcano can be defined as an opening in a planet through which lava, gases, and molten rock come out. Earthquake activity around a volcano can give plenty of insight into when it will erupt. The liquid inside a volcano is called magma (lava), which can harden.
Essays About Volcanoes: Top 5 Examples And 10 Prompts
Top 5 Essay Examples. 1. Short Essay on Volcanoes by Prasad Nanda. "The name, "volcano" originates from the name Vulcan, a god of fire in Roman mythology.". Nanda briefly defines volcanoes, stating they help release hot pressure that builds up deep within the planet.
Informative Essay on Volcanoes
Informative Essay on Volcanoes. This essay sample was donated by a student to help the academic community. Papers provided by EduBirdie writers usually outdo students' samples. To start off, I am going to tell you what a volcano is, what they do, what's their purpose, how they have formed what types of volcanoes they are, and their anatomy ...
Essay on Volcano
A volcano is a crack in the Earth's surface where molten rock, ash, and gases from deep inside the Earth come out. Think of it like a soda bottle that's been shaken up. When you open the cap, everything rushes out because of the pressure. In the same way, when a volcano erupts, it releases pressure from beneath the Earth's crust.
Volcano facts and information
Volcanoes, explained. These fiery peaks have belched up molten rock, hot ash, and gas since Earth formed billions of years ago. Volcanoes are Earth's geologic architects. They've created more than ...
33 Writing Prompts about Volcanoes
33 Writing Prompts about Volcanoes. Mount St. Helens blew its top and captured the imagination and fear of Americans everywhere. Of course, the destruction brought on by Mount St. Helens was nothing compared to the devastation of Krakatoa or the splendor of Vesuvius. However, apart from being volcanoes, all of these events managed to capture ...
Different Types of Volcanoes: [Essay Example], 618 words
Volcanoes are diverse and complex geological formations that play a crucial role in shaping the Earth's surface and influencing global climate. The different types of volcanoes—shield volcanoes, stratovolcanoes, calderas, cinder cones, and submarine volcanoes—each have their own unique characteristics and geological processes.
How to Write a Report on Volcanoes
Pressure causes a multitude of physical actions to occur. Combine heat and pressure and you may create a volcano. Begin your report by explaining how magma -- hot, liquid rock below the earth -- rises because its density is less than the density of the surrounding rocks. The distance the magma moves vertically depends on factors such as the ...
70 Volcano Essay Topic Ideas & Examples
The Volcano and Aurora in Iceland. In other words, the volcano Hekla was erupting from the surface of the earth while the natural light was shining from the sky. Hawaii - A Volcano in the Sea. All the volcanoes in Hawaii are shield volcanoes. They are large and have shallow-sloping sides - almost like a warrior's shield.
Volcanoes and Their Characteristics
A cone-shaped mountain that is the result of this process is called a cinder cone volcano. These volcanic mountains are the smallest ones of all types and are generally less in their size than 500 meters. An example of such a volcanic mountain is SP Mountain situated in Arizona, and belonging to the Colorado Plato.
Exploring Volcanoes: From Formation to Societal Resilience: [Essay
The essays presented here offer a multifaceted exploration of volcanoes, shedding light on their formation, characteristics, environmental impacts, and societal responses. Volcanoes, as powerful geological phenomena, shape our planet's landscapes and ecosystems while posing significant hazards to human societies.
1 Introduction
FIGURE 1.1 NASA Ozone Monitoring Instrument observations of the SO 2 cloud produced by the August 7, 2008, eruption of Kasatochi (Aleutian Islands, Alaska) drifting over the lower 48 states and Canada on August 15, 2008. Satellite observations such as these are crucial for mitigating aviation hazards due to drifting volcanic clouds and for assessing the impact of volcanic eruptions on Earth ...
The Environmental Effects of Volcanoes: a Comprehensive Analysis
In this essay, I will explore the myriad ways in which volcanoes affect the environment, including air pollution, climate change, and the creation of new landmasses. We will also examine the relationship between humans and volcanoes, exploring how we can mitigate the environmental impacts of these powerful geological forces.
Volcanoes
A volcano is an opening in a planet or moon's crust through which molten rock, hot gases, and other materials erupt. Volcanoes often form a hill or mountain as layers of rock and ash build up from repeated eruptions. Volcanoes are classified as active, dormant, or extinct. Active volcanoes have a recent history of eruptions; they are likely ...
Volcano Essay In English
A volcano essay can be both informative and exciting for students studying them. Educating students about volcanoes through research and writing can help the...
Essay on Volcanoes
Essay # 3. Formation of Volcanoes: The term volcano is used to mean both the opening in the earth's crust, i.e. the vent through which the eruption of magma occurs as well as the hill built- up by the erupted material. Volcanoes occur where the cracks in the earth's crust lead to the magma chamber.
volcano
A volcano is an opening in Earth 's crust. When a volcano erupts, hot gases and melted rock from deep within Earth find their way up to the surface. This material may flow slowly out of a fissure, or crack, in the ground, or it may explode suddenly into the air. Volcanic eruptions may be very destructive. But they also create new landforms. ...
Volcano Essays: Examples, Topics, & Outlines
Volcanic Hazards. hen Mount St. Helens exploded on May 18, 1980, there was no red hot lava flowing down from the top of the mountain. But there was an enormously powerful blast that permanently altered the landscape. This kind of explosive blast from a volcano is considered to be the most violent.
Essay on Volcanoes
Volcanoes. Volcanoes are natural phenomena which are on the Earth's surface through which molten rock and gases escape from below the surface (Tarbuck, 139). These volcanoes are very interesting to observe and to study because of their amazing occurrences and majestic lava eruptions. Volcanoes have been studied ever since the beginning of ...
Summary
Summary. Volcanoes are a key part of the Earth system, and open a window into the inner workings of the planet. More than a dozen volcanoes are usually erupting on Earth at any given time.
Volcanoes: Compilation of Essays on Volcanoes
Essay # 1. Meaning of Volcanoes: Sometimes the molten rock, ash, steam and other gases find their way to the surface of the earth through some vents or openings. These ejected materials accumulate around the vent and give rise to a volcanic cone or a hill. The conical hill along with the vent is known as volcano.
Explainer: The volcano basics
October 1, 2014 at 12:57 pm. A volcano is a spot in Earth's crust where molten rock, volcanic ash and certain types of gases escape from an underground chamber. Magma is the name for that molten rock when it's below ground. Scientists call it lava once that liquid rock erupts from the ground — and may start flowing across Earth's surface.
Informative Text Writing Task
This informational prompt guides students through researching, planning, and writing an informative text called Why Do Volcanoes Erupt? The students will need to: research the topic. record bullet point notes on the template provided. write up their text in complete sentences on the scaffold provided.
WATCH
About 50 to 70 volcanoes erupt per year, according to the British Geological Survey. Some parts of the world, such as Iceland, are prone to volcanic activity. The last time a volcano erupted in ...
How To Start A Business In 11 Steps (2024 Guide)
The best way to accomplish any business or personal goal is to write out every possible step it takes to achieve the goal. Then, order those steps by what needs to happen first. Some steps may ...
Rivers of Lava on Venus Reveal a More Volcanically Active Planet
By Robin George Andrews. May 27, 2024, 11:00 a.m. ET. Witnessing the blood-red fires of a volcanic eruption on Earth is memorable. But to see molten rock bleed out of a volcano on a different ...
Memorial Day: A day to remember those who died in military service
Memorial Day is the unofficial start of summer. It's a time to gather with friends and family for a grill out, a picnic, or maybe a trip to the beach to soak up the sun. ... So, when you chow down ...
When Should You Start Writing Your College Essay?
Students who have numerous supplement essays should aim to complete them by October 31st. It will allow you to concentrate on your senior year, where maintaining high grades is crucial, and also have ample time to respond to any potential deferrals or waitlist decisions. When to write college essay depends on your goals and commitments other ...