The True Nature of a Volcano
When we think of volcanoes, often the image that comes to mind is a catastrophic Hollywood-worthy explosion. Actually, there are different types of volcanoes—some are very dangerous, while others are not. In order to understand the true nature of a volcano, it is important to know what kind it is.
Geologists and professional volcanologists usually classify volcanoes into four different types based on their shape, magnitude, structure, material, and type of eruption.
Four Major Types of Volcanoes
- Cinder Cone, aka Scoria Cone
- Composite, aka Strato
- Lava Dome
This article will also answer such questions as: What is a volcano? What are the three states of volcanoes? What are the most dangerous volcanoes in the world? What are the tallest volcanoes in the world? Do volcanoes exist on other planets? What do you do when a volcano erupts? And, what is the Yellowstone Caldera?
Different Types of Volcanoes
|Type of Volcano||Shape||Height||Slope|
Cinder Cone, AKA Scoria Cone
Up to 1,200 feet (370 meters)
Tall and broad
Up to over 30,000 feet (9,000 meters)
Roughly 10 degrees near the base and 5 degrees near the top
Composite, AKA Strato
Tall, steep, and symmetrical
Up to 8,000 feet (2,400 meters)
Roughly 6 degrees near the base and roughly 30 degrees near the top
Up to 330 feet (100 meters)
1. Cinder Cone, aka Scoria Cone
Examples of cinder cone volcanoes: Paricutín in Mexico, Lava Butte, Sunset Crater
One of the most common types of volcanoes is the cinder cone. Less dangerous compared to other types, cinder cones only grow to about 1,000-1,200 feet tall. Unlike some other types of volcanoes—shield and composite volcanoes—cinder cones are usually created from a single opening. The opening of a cinder cone is a cone-shaped structure, while the steeps are formed of the erupted, fragmented cinders that fall close to the chimney/vent.
The manner of eruption for cinder cones is relatively simple. When the lava erupts, its cinders of it are blown into the air. These fragmented cinders fall a short distance from the opening, thus creating the cone.
2. Shield Volcanoes
Examples of shield volcanoes: Hualalai, Mauna Loa, Kohala Volcano
Another type of volcano is the shield volcano. Unlike cinder cones, shield volcanoes can be very big in size. However, they are not as dangerous as that size might make it seem. This is because the eruption of lava out of shield volcanoes is not accompanied by pyroclastic material (bursts of gas and particles).
Shield volcanoes may be tall but tend to be very broad, with less steep slopes than other volcanoes.
Shield volcanoes can be huge because of their ample supply of magma. For example, Mauna Loa is a shield volcano that rises more than 30,000 feet above its base on the bottom of the ocean.
3. Composite Volcanoes
Examples of composite volcanoes: Mount Fuji, Mount Shasta, Mount St. Helens, Mount Rainier
Composite volcanoes are also known as stratovolcanoes. Composite volcanoes are reasonably big and can rise up 8,000-10,000 feet. Moreover, they can range anywhere from 1-10 km in diameter. Their eruptions are dangerous and explosive in nature, with many layers of lava and pyroclastic materials, the current of rock and gas that can reach 1,800°F and 450 mph, killing any living organism in its path immediately. The citizens of Pompeii were killed by a composite volcano's pyroclastic flow.
The general structure of composite volcanoes is tall and symmetrical and with steep sides. Commonly, composite volcanoes erupt hot gases, ash, lava, and pumice as well as stiff, slow-moving lava. Moreover, deadly mudflows—commonly known as ‘lahars’—can accompany the eruption.
Composite volcanoes are believed to kill the most people because of their deadly nature and high numbers. Apart from their dangerous side, composite volcanoes are also famous because they comprise some of the most beautiful mountains on planet Earth. For example, Mount Fuji in Japan and Mount Shasta in California are two famous composite volcanoes.
4. Lava Dome Volcano
Examples of lava dome volcanoes: There are lava domes within the crater of Mount St. Helens, Chaitén lava dome, Lassen Peak
Lava domes are the fourth type of volcano that we are going to discuss. Unlike composite and shield volcanoes, lava domes are of significantly smaller stature. They are formed when the lava is too viscous to flow to a great distance. As the lava dome slowly grows, the outer surface cools and hardens as the lava continues to pile within. Eventually, the internal pressure can shatter the outer surface, causing loose fragments to spill down its sides. Generally, such lava domes are found on the flanks of larger composite volcanoes.
So, the bottom line is that there are four different types of volcanoes, each with a different set of characteristics and structure. Some are more dangerous and catastrophic than others. Having this knowledge keeps you informed about the different types of volcanoes.
Want to read further on how volcanoes form? Rosalyn M. C. Lopes' The Volcano Adventure Guide breaks the process down in detail starting on page 38.
What Is a Volcano?
A volcano is a vent that directly connects magma to the surface of the Earth. It is also described as a mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth's crust.
Three States of Volcanoes
There are three states of volcanoes, which are important in completely grasping the topic. These three states are:
- Extinct Volcanoes
- Dormant Volcanoes
- Active Volcanoes
Extinct volcanoes will never erupt again.
Ben Nevis, the tallest mountain in Scotland, and the British Isles.
Dormant volcanoes have been in the state of sleep or dormancy for a very long period of time—usually at least 2,000 years. However, dormant volcanoes are not extinct and, hence, could erupt at any time.
Active volcanoes are considered as immediate threats. Lava and gases may erupt from these volcanos, and/or these volcanoes may show seismic activities. An active volcano may have erupted recently and is at a risk of erupting again.
Mauna Loa, Hawaii
Most Dangerous Volcanoes
Composite volcanoes are some of the most dangerous volcanoes on the planet. A composite volcano is formed over hundreds of thousands of years through multiple eruptions. The eruptions build up the composite volcano, layer upon layer until it towers thousands of meters tall. Some layers might be formed from lava, while others might be ash, rock and pyroclastic flows. A composite volcano can also build up large quantities of thick magma, which blocks up inside the volcano, and causes it to detonate in a large volcanic explosion. Even larger, calderas, such as the Yellowstone caldera, are mind-boggling powerful, with the capacity to cover the entire U.S. in ash.
Most Dangerous Volcanoes in the World
A volcano composed of several foci that since 1572 have erupted on 33 occasions, the last one in 1977.
On August 27, 1883, four huge explosions—which could be heard up to 5,000 kilometres away—destroyed almost three quarters of the archipelago of Krakatoa (or Krakatau) in what is now Indonesia.
Considered the most active volcano in Indonesia, it has been erupting almost continuously since the sixteenth century.
This volcano is a scant 70 kilometres that separate the volcano from the 20 million inhabitants of Mexico City.
If this island volcano erupts it could cause the entire face to collapse westward and provoke a mega-tsunami that could cross the Atlantic and devastate the American east coast.
Canary Islands, Spain
Italy’s Vesuvius has been a menacing figure since an eruption in 79 CE buried the city of Pompeii.
The heat from Mount Rainier’s lava flows could potentially melt the snow and ice on the volcano, causing a rapid downstream flow of mud, rocks and debris called lahar.
Earth's crust is around three to 37 miles thick. It is broken up into seven major and 152 smaller pieces called tectonic plates. These plates float on a layer of magma (semi-liquid rock and dissolved gases). At the boundaries of these plates they move past, are pushed under, or move away from each other. The magma (which is lighter than the surrounding solid rock) is often able to force its way up through cracks and fissures. Magma that has erupted is called lava.
The world's largest volcano, Mauna Loa in Hawaii, is a shield volcano. Mauna Loa is about 55,770 feet from its base, which is deep beneath the ocean to the summit. It's summit is 13,681 feet above sea level. It is one of the Earth's most active volcanoes. Shield volcanoes have a reputation for being powerful and enormous.
Tallest Volcanoes in the World
Ojos del Salado
Andes on the Argentina–Chile border
Southern Peruvian Andes
The border of Chile and Bolivia
Do Volcanoes Exist on Other Planets?
Volcanoes are a fairly regular feature on rocky planets and moons. For example, the surface of Venus is dominated by volcanic features. It has more volcanoes than any other planet in the Solar System.
Scientists have never recorded an active volcano eruption on the surface of Mars. However, Mars has the tallest dormant volcano in the solar system, Olympus Mons.
With over 400 active volcanoes, Io is the most volcanically active object in the Solar System. This extreme geologic activity is the result of tidal heating from friction generated within its interior as it is pulled between Jupiter, Europa, Ganymede, and Callisto.
What Do You Do When a Volcano Erupts?
When a large volcano erupts, it's one of the most devastating events in the natural world. Those who are unprepared can die in numerous ways. If a volcano erupts in your area, there are several things you'll need to do in order to survive
To survive a volcanic eruption you'll need to:
- Evacuate only as recommended by authorities to stay clear of lava, mud flows, and flying rocks and debris.
- Before you leave the house, change into long-sleeved shirts and long pants and use goggles or eyeglasses, not contacts.
- Wear an emergency mask or hold a damp cloth over your face.
- Stay away from areas downwind from the volcano to avoid volcanic ash.
- Stay indoors until the ash has settled unless there is a danger of the roof collapsing.
What Is the Yellowstone Caldera?
Location: Yellowstone National Park, Wyoming, United States
Mountain range: Rocky Mountains
The last time the Yellowstone supervolcano erupted was over 640,000+ years ago. The eruption area collapsed upon itself, creating a gigantic sunken crater or caldera that is 1,500 square miles in area. The magmatic heat powering that eruption still powers the park’s famous geysers, hot springs, fumaroles, and mud pots.
Yellowstone is technically a "supervolcano." The term “supervolcano” implies an eruption of magnitude 8 on the Volcano Explosivity Index. This indicates an eruption of more than 1,000 cubic kilometers of magma. The yellowstone eruptions 6,000 years ago was estimated to be 2,500 times larger than the May 18, 1980 eruption of Mt. St. Helens in Washington State.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Sydney Marie Corrigan on May 26, 2020:
Here there are videos that I watched and I watched a lot of them
Titus Philip on May 23, 2020:
I search for types of volcanoes
Paul Mulligan on December 22, 2019:
A very educational video. It would be interesting to know how many of the worlds most active volcanoes have seismic probes that measure seismic activity and weather this can provide predictive capacity for possible eruptions.Here in Australia we are lucky enough not to have any active volcanoes . Unfortunately there was an eruption in New Zealand to the East of us that caused fatalities to a number of tourists.Hopefully future scientific research will become more accurate in mappng and disseminating knowledge making public those places that tourists should steer clear of
Michael Weston on December 17, 2019:
Thank you for sharing
Jenes urio on December 03, 2019:
i got a good idea i never have it before.
bruh on October 27, 2019:
gang on October 22, 2019:
? on July 28, 2019:
I like it soooooooooooooooo much
marisol on May 06, 2019:
this does not help me out
KINGSTON on April 16, 2019:
WOW!, that is the most interesting volcano text I ever read.
chizkiyah richmond on April 03, 2019:
this website is the best one yet, I looked at all of the other websites and they were not near to as good as this one,
thank you very much *_*
Geo Student on December 16, 2018:
Just wanted to make note that Mt. St. Helens is a Stratovolcano, not a lava dome.
That guy from Nz on November 14, 2018:
I live on the side of a cinder cone lol
And an Island just out at sea is a shield volcano
...and farther south we have composite volcanoes
@jairah on November 10, 2018:
Nordlys on June 03, 2018:
The volcano I saw is a stratovolcano, the most famous and among the most dangerous: Mount Vesuvius.
a guy on May 22, 2018:
ana maria orantes u are passionate
Ana Maria Orantes from Miami Florida on May 17, 2018:
Thank you for responding my comment mister boiiii.
Ana Maria Orantes from Miami Florida on May 17, 2018:
Did you see what it is going on with Hawaii volcanoes. El Salvador Central America has a team of scientists working and monitoring the volcanoes activity. If you used you tub . They explain what it is going on. The video is in Spanish language.
boiiii on May 16, 2018:
thx so much this was so much help
yei boiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii on May 16, 2018:
thanks sooooo much i just had a paper on this in class and this helped so much volcanoes are really cool thanks
Ana Maria Orantes from Miami Florida on May 10, 2018:
Hello mister Said. I was reading your hub. Congratulations to you. Volcanoes are so dangerous to all of us. I saw what happened in Hawaii and still going on. Your explanation is very important to the people in Hawaii and to others. The shoes to walk around the hot areas have to be from a good rubber to protect the feet; lava is so hot that can burn the skin. Thank you for the information.
caleb on May 09, 2018:
this video was cooooooooolllllllll i like jeffy from sml .
Ashten on May 02, 2018:
Thanks i needed this website for a paper and came very handed i will be sure to leave a Source.
Gia on April 06, 2018:
Thanks for the info, I really needed somthing good for a project and this was the best infomation that I found. Thanks!
adr on March 20, 2018:
helps so much thanks
GnarlyNinja7 on February 22, 2018:
devn on February 21, 2018:
Cristhel Mae C. Escatron on February 11, 2018:
This helped me a lot in my assignment thank you very much for doing this.☺
princess myrna austria on February 07, 2018:
helped me a lot with my assignments,thank you so much
xXxnarutoboyxXx on February 06, 2018:
Kennady Velo on February 02, 2018:
I'm a sixth grader, and this helped me with my homework, thank you sir, I appreciate it.
cocola on January 26, 2018:
helped me with a paper thx
amazing kris on January 22, 2018:
VERY ,VERY,VERY NICE
Mister on December 09, 2017:
This helped me with a mistery thank you
Pennywise The Dancing Clown on November 30, 2017:
nobody knows on November 28, 2017:
hey that's pretty good
cow2 on November 01, 2017:
cloie come on
cow2 on November 01, 2017:
abby on October 30, 2017:
helped me a lot with my essay, thank you so much
Cokeinhaler on September 03, 2017:
hey that's pretty good
Bakar Suleiman on August 21, 2017:
itis good notes
Colton jarosz on June 12, 2017:
This did not help me ;3(
jesus javier cuadra on May 25, 2017:
this helped me really much
Jimbobway on May 19, 2017:
Very Very Good In Opinion
paige on April 11, 2017:
june on March 30, 2017:
thanks ,this is a good writing
may on March 30, 2017:
orcblat on March 30, 2017:
you are great people and this author is awsome. kaboom!!
MAWSHIN on March 21, 2017:
junior.Damai on February 23, 2017:
Thanks for they information
SONE on February 16, 2017:
jhon on February 13, 2017:
awesome not it was bad to the baadd
Kyla on November 30, 2016:
This really helps
erik on November 29, 2016:
aiden on November 29, 2016:
its really fun thankyou
marwin on November 24, 2016:
i like it. it was great.
allison on November 17, 2016:
sort of helpful but didn't find what I was looking for
WWednsdee on November 16, 2016:
Cool... Very Factual
Jim on October 04, 2016:
Thanks for this explanation. I'm taking a geology course and this really helps!
p on September 14, 2016:
very good site
cool on September 14, 2016:
volcanohater#1 on May 24, 2016:
I ment dume
vocanohatr#1 on May 24, 2016:
this is a stupid website
calito on January 14, 2016:
this is very good for students to learn.thanks for the info
Awesomeness on October 15, 2015:
erich marie alcaide on October 09, 2015:
good news i had search
abdulohbp;y./ 06bp76 on September 28, 2015:
this is useless
attaullah on September 28, 2015:
this is goooooooooooooood
Deanna Amodeo from Big Island on May 07, 2015:
This is awesome. I lived on the big island in Pahoa, and had a lava flow not even a mile away from me!
Emily on April 13, 2015:
this really helped me
King Peter the magnificent on March 09, 2015:
volcanoes are awesome
Kristen Howe from Northeast Ohio on March 05, 2015:
This was a fascinating hub on the different types of volcanoes. There are always beautiful to see and dangerous to be near at the same time. Voted up!
jhoy on January 29, 2015:
thanks a lot ((: GB
analiza on December 09, 2014:
The wolf on December 05, 2014:
Wow, good job! This was very informative and it really helped with my paper for Earth Science!
Leria on November 24, 2014:
thank you for the info :)
Pj on November 19, 2014:
I can use it to be my answer in my assignment
Snakesmum on October 01, 2014:
Volcanoes are awesome, and I've stood on the outer crater of one which was in minor eruption at the time. It was one of the great experiences of all time for me. We weren't allowed into the crater to the lower level though, as it was too active to go down and see the lava lake.
Pauleee on September 25, 2014:
great service :)
luke on August 10, 2014:
Ana Maria Orantes from Miami Florida on May 19, 2014:
I like your article on the volcanos. Volcanos are the most dangerous activity that the earth have. Volcanos are destructive . Every time, I see a volcano active on television. I feel worry about the scientists that work on the volcanos. Other people around , they are smart . They leave fast. You did a marvelous job on your hub. Thank you for sharing your good work.
shinga on May 09, 2014:
I am really happy with your service
Avinesh Prahladi from Chandigarh on November 04, 2013:
I must say that it's a nice & an interesting theme for a hub. Keep posting such interesting hubs.
Twilight Lawns from Norbury-sur-Mer, Surrey, England. U.K. on October 18, 2013:
Not so close neighbours now, my friend. I moved a few miles down the road to London, UK.
Syed Hunbbel Meer (author) from Karachi, Pakistan. on October 17, 2013:
@Mel: Indeed. It is very scary, and walking there must be fascinating and interesting :)
@vibesites: It must have been a great experience hiking there. Great to hear about that and thanks for stopping by :)
Syed Hunbbel Meer (author) from Karachi, Pakistan. on October 17, 2013:
@Twilightlawns: Yes, I have :) In fact, consider me your neighbor. I'm from Karachi :)
vibesites from United States on October 17, 2013:
This is really interesting.. The Philippines' Mayon Volcano is also a good composite (and active) volcano btw, having the perfect shape. I've hiked there once and fortunately I've returned in one piece. :)
The works of Mother Nature is always interesting and awe-inspiring
Mel Carriere from Snowbound and down in Northern Colorado on October 06, 2013:
Very concise and interesting summary. I have been to Sunset Crater and was fascinated walking through the lava flows. It is sort of scary to think that major cities like Seattle are located at the foot of deadly volcanoes. Nice work!
Twilight Lawns from Norbury-sur-Mer, Surrey, England. U.K. on October 04, 2013:
A really very interesting hub. Thank you.
I have always been fascinated by volcanoes and loved it when we studied them at school.
Your hub was easy to read and struck just the right balance between really interesting and very informative, without being tedious.
By the way, I feel that my interest in volcanoes may stem from the fact that i was born in a city that is build in the crater of an extinct volcano.
I think you must have heard of it... Quetta, in Baluchistan.
judy ann on August 16, 2013:
wonderful!!!!@ interesting huh..
jacob noonan on June 17, 2013:
i use this website all the time for high school research paers. love the website
Syed Hunbbel Meer (author) from Karachi, Pakistan. on January 18, 2013:
@Livingsta and @Joseph: Thank you for stopping by :)
Joseph Muendo from Nairobi, Kenya on January 18, 2013:
Interesting and informative
livingsta from United Kingdom on December 06, 2012:
Interesting hub, thank you for sharing!
Syed Hunbbel Meer (author) from Karachi, Pakistan. on December 06, 2012:
Thank you, Vellur, for stopping by. Volcanoes always intrigues me and I hope that by studying these 4 different types of Volcanoes, people will understand them better.
Nithya Venkat from Dubai on December 05, 2012:
Volcanoes very well explained, thank you for sharing this with us. Voted up and shared.