Types of Volcanoes: Shield, Cinder Cones & Composite Cones - Video & Lesson Transcript | Study.com Types of Volcanoes: Shield, Cinder Cones & Composite Cones Watch short & fun videos Start Your Free Trial Today An error occurred trying to load this video. Try refreshing the page, or contact customer support. You must create an account to continue watching Register for a free trial Are you a student or a teacher? I am a student Start Your Free Trial To Continue Watching As a member, you'll also get unlimited access to over lessons in math, English, science, history, and more. Plus, get practice tests, quizzes, and personalized coaching to help you succeed. Coming up next: Volcanic Eruption: Gases Released & Their Effects You're on a roll. Keep up the good work! Your next lesson will play in 10 seconds 0:06 Volcanoes Add to Add to Add to Want to watch this again later? Log in or sign up to add this lesson to a Custom Course. Custom Courses are courses that you create from Study.com lessons. Use them just like other courses to track progress, access quizzes and exams, and share content. Teachers Organize and share selected lessons with your class.

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Gillaspy has taught health science at University of Phoenix and Ashford University and has a degree from Palmer College of Chiropractic. The earth ejects lava, rock fragments, hot vapor and gases during volcanic eruptions. Volcanoes vary based on size, shape, composition and eruptive style. Learn about the different types of volcanoes, such as shield, cinder cone and composite cone. Volcanoes Volcanoes are a good way for the earth to blow off a little steam. More correctly, volcanoes are vents in the earth's crust through which lava, rock fragments, hot vapor and gases are ejected. And, while they are all natural events in the life of Earth, there are different types of volcanoes. The types of volcanoes are differentiated based on their size, composition and explosive style. In fact, we could compare the different types of volcanoes to players on a football team. The tall and impressive composite cone volcanoes are much like the strong and confident quarterback. The broad and lower-to-the-ground shield volcanoes are much like the beefy lineman of the team. And, the fast-growing but smaller cinder cone volcanoes are much like the quick-moving and compactly built running backs of our team.

Let's take a closer look at these three main types of volcanoes. Composite Cone Volcanoes Composite cone volcanoes, which are also called 'stratovolcanoes' or simply 'composite volcanoes,' are cone-shaped volcanoes composed of layers of lava, ash and rock debris. Composite cone volcanoes are grand sites and can grow to heights of 8,000 feet or more. Mount St. Helens and Mount Rainier, which are both found in Washington State, are impressive examples of composite volcanoes. These steep-sided volcanoes erupt in an explosive manner. In fact, Mount Vesuvius is a composite volcano that is most famous for burying the ancient Roman city of Pompeii in up to 20 feet of volcanic ash in 79 AD. The explosiveness of their eruptions is due to the thick, highly viscous lava that is produced by composite cone volcanoes. And, this viscous lava has a lot to do with why they are shaped the way they are. The thick lava cannot travel far down the slope of the volcano before it cools. This makes the sides of the composite volcano steep.

These explosive volcanoes also spew out eruptions of small rock and ash, which gets deposited on the sides of the volcano. Therefore, we see that composite volcanoes are composed of alternating layers of hardened lava, volcanic ash and rock fragments, which is why they are called 'composite.' Shield Volcanoes Shield volcanoes are broad, domed-shaped volcanoes with long, gently sloped sides. If you were to fly over top of a shield volcano, it would resemble a warrior's shield, hence the name. These volcanoes can cover large areas but never grow very tall. The reason these volcanoes tend to flatten out is due to the composition of the lava that flows from them, which is very fluid. This more fluid lava spreads out in all directions but cannot pile up in steep mounds. Shield volcano eruptions are less explosive than composite volcanoes, as the lava tends to pour out of the volcano's vent, creating the low-profile layers of lava that are characteristic of these volcanoes. The Hawaiian Islands are actually the tops of gigantic shield volcanoes rising from the ocean basin.

Cinder Cone Volcanoes Cinder cone volcanoes are steep, cone-shaped volcanoes built from lava fragments called 'cinders.' These volcanic cinders, also known as 'scoria,' are glassy volcanic fragments that explode from the volcano and cool quickly. Therefore, they do not fall far from the vent of the volcano, and this builds the steep sides of the cinder cone volcanoes fairly quickly. × Volcanoes: Principal Types of Volcanoes Principal Types of Volcanoes Geologists generally group volcanoes into four main kinds--cinder cones, composite volcanoes, shield volcanoes, and lava domes. Cinder cones Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone. Most cinder cones have a bowl-shaped crater at the summit and rarely rise more than a thousand feet or so above their surroundings. Cinder cones are numerous in western North America as well as throughout other volcanic terrains of the world. Schematic representation of the internal structure of a typical cinder cone.

In 1943 a cinder cone started growing on a farm near the village of Parícutin in Mexico. Explosive eruptions caused by gas rapidly expanding and escaping from molten lava formed cinders that fell back around the vent, building up the cone to a height of 1,200 feet. The last explosive eruption left a funnel-shaped crater at the top of the cone. After the excess gases had largely dissipated, the molten rock quietly poured out on the surrounding surface of the cone and moved downslope as lava flows. This order of events--eruption, formation of cone and crater, lava flow--is a common sequence in the formation of cinder cones. During 9 years of activity, Parícutin built a prominent cone, covered about 100 square miles with ashes, and destroyed the town of San Juan. Geologists from many parts of the world studied Parícutin during its lifetime and learned a great deal about volcanism, its products, and the modification of a volcanic landform by erosion. Parícutin Volcano, Mexico, is a cinder cone rising approximately 1,200 feet above the surrounding plain.

Composite volcanoes Some of the Earth's grandest mountains are composite volcanoes--sometimes called stratovolcanoes. They are typically steep-sided, symmetrical cones of large dimension built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs and may rise as much as 8,000 feet above their bases. Some of the most conspicuous and beautiful mountains in the world are composite volcanoes, including Mount Fuji in Japan, Mount Cotopaxi in Ecuador, Mount Shasta in California, Mount Hood in Oregon, and Mount St. Helens and Mount Rainier in Washington. Most composite volcanoes have a crater at the summit which contains a central vent or a clustered group of vents. Lavas either flow through breaks in the crater wall or issue from fissures on the flanks of the cone. Lava, solidified within the fissures, forms dikes that act as ribs which greatly strengthen the cone. The essential feature of a composite volcano is a conduit system through which magma from a reservoir deep in the Earth's crust rises to the surface. The volcano is built up by the accumulation of material erupted through the conduit and increases in size as lava, cinders, ash, etc., are added to its slopes.

Schematic representation of the internal structue of a typical composite volcano. When a composite volcano becomes dormant, erosion begins to destroy the cone. As the cone is stripped away, the hardened magma filling the conduit (the volcanic plug) and fissures (the dikes) becomes exposed, and it too is slowly reduced by erosion. Finally, all that remains is the plug and dike complex projecting above the land surface--a telltale remnant of the vanished volcano. Shishaldin Volcano, an imposing composite cone, towers 9,372 feet above sea level in the Aleutian Islands, Alaska. An interesting variation of a composite volcano can be seen at Crater Lake in Oregon. From what geologists can interpret of its past, a high volcano--called Mount Mazama- probably similar in appearance to present-day Mount Rainier was once located at this spot. Following a series of tremendous explosions about 6,800 years ago, the volcano lost its top. Enormous volumes of volcanic ash and dust were expelled and swept down the slopes as ash flows and avalanches. These large-volume explosions rapidly drained the lava beneath the mountain and weakened the upper part.

The top then collapsed to form a large depression, which later filled with water and is now completely occupied by beautiful Crater Lake. A last gasp of eruptions produced a small cinder cone, which rises above the water surface as Wizard Island near the rim of the lake. Depressions such as Crater Lake, formed by collapse of volcanoes, are known as calderas. They are usually large, steep-walled, basin-shaped depressions formed by the collapse of a large area over, and around, a volcanic vent or vents. Calderas range in form and size from roughly circular depressions 1 to 15 miles in diameter to huge elongated depressions as much as 60 miles long. Crater Lake, Oregon; Wizard Island, a cinder cone, rises above the lake surface. The Evolution of a Composite Volcano A. Magma, rising upward through a conduit, erupts at the Earth's surface to form a volcanic cone. Lava flows spread over the surrounding area. B. As volcanic activity continues, perhaps over spans of hundreds of years, the cone is built to a great height and lava flows form an extensive plateau around its base. During this period, streams enlarge and deepend their valleys. C.

When volcanic activity ceases, erosion starts to destroy the cone. After thousands of years, the great cone is stripped away to expose the hardened "volcanic plug" in the conduit. During this period of inactivity, streams broaden their valleys and dissect the lava plateau to form isolated lava-capped mesas. D. Continued erosion removes all traces of the cone and the land is worn down to a surface of low relief. All that remains is a projecting plug or "volcanic neck," a small lava-capped mesa, and vestiges of the once lofty volcano and its surrounding lava plateau. Shield volcanoes Schematic representation of the internal structure of a typical volcanic dome. Volcanic or lava domes are formed by relatively small, bulbous masses of lava too viscous to flow any great distance; consequently, on extrusion, the lava piles over and around its vent. A dome grows largely by expansion from within. As it grows its outer surface cools and hardens, then shatters, spilling loose fragments down its sides.

Some domes form craggy knobs or spines over the volcanic vent, whereas others form short, steep-sided lava flows known as "coulees." Volcanic domes commonly occur within the craters or on the flanks of large composite volcanoes. The nearly circular Novarupta Dome that formed during the 1912 eruption of Katmai Volcano, Alaska, measures 800 feet across and 200 feet high. The internal structure of this dome--defined by layering of lava fanning upward and outward from the center--indicates that it grew largely by expansion from within. The Novarupta Dome formed during the 1912 eruption of Katma Volcano, Alaska. Mont Pelée in Martinique, Lesser Antilles, and Lassen Peak and Mono domes in California are examples of lava domes. An extremely destructive eruption accompanied the growth of a dome at Mont Pelée in 1902. The coastal town of St. Pierre, about 4 miles downslope to the south, was demolished and nearly 30,000 inhabitants were killed by an incandescent, high-velocity ash flow and associated hot gases and volcanic dust.

Only two men survived; one because he was in a poorly ventilated, dungeon-like jail cell and the other who somehow made his way safely through the burning city. A sketch of the havoc wrought in St. Pierre Harbor on Martinique during the eruption of Mont Pelée in 1902. Cochise College P Composite volcanoes, also known as stratovolcanoes, make up some of the most known volcanoes that we have here on earth. A composite volcano is made up of many layers of hardened lava and volcano ash from eruptions that have already taken place. That is usually why they can make such peaks because of the constant overlapping that occurs. They really make beautiful mountains and draws people close to them and that usually isnï¿½t good because when these volcanoes blow they are usually violent and have a higher number of casualties than other volcanoes. Like I said before, composite volcanoes are made of an overlapping of lava flows that come out when there is an explosion. All the lava that comes out during like minor explosions usually doesnï¿½t get too far, so what is left just keeps getting piled and piled on top of each other.

While the lava keeps piling up this is what causes for the high steep tops of these volcanoes. Also during these eruptions cinder bombs and blocks are thrown out and so when the next eruption occurs the lava flows cement these all together also adding height to the volcano. These volcanoes mostly always have violent eruptions. The eruption is caused by the viscous magma, when it rises to the top it usually clogs up the crater pipe and gases in the crater pipe get locked up. So the pressure will increase and also the magnitude of the eruption. During these eruptions the volcanoes will throw out debris, have lots of lava flows, and they can also create landslides, avalanches and even tsunamis. The eruptions of these volcanoes cause the most damage than any of the rest. Some of the most well known volcano eruptions are from composite volcanoes like Mt. St Helens, Mt. Fuji and Mt. Etna. Cinder cones are a very classic look that a volcano can have. They have a bowl shaped crater at the top of the summit. The rock fragments, cinders are glassy and contain gas bubbles frozen into place as the magma explodes and is thrown into the air and is cooled quickly.

So basically they are made up of ash and not lava. These volcanoes grow rapidly and made there maximum size fairly quickly. Cinders cones can become fairly large. Cinders are commonly found on the flanks of shield and stratovolcanoes. The eruptions of cinder volcanoes are usually not that harmful to the human population. There eruptions can vary from being violent to non-violent. Their eruptions do have blobs of lava thrown out but all that usually cools very soon as it hits and air and a lot of it goes to the structure of the volcanoes, by again making it is what it is. vulcan.wr.usgs.gov/Imgs/Jpg/Hawaii/Images/Mau... Shield volcanoes are very large in size; the picture above shows an example of one which is the largest volcano on earth, Mauna Lau. They are formed by lava flows of low-viscosity, so over time and flow after flow, it is what makes the mountain grow. They can get so big that they have been confused with mountain ranges. Shield volcanoes are not only huge on earth but the largest mountain in our solar system Olympus Mons is a shield volcanoes. They are pretty common volcanoes.

Shield volcanic eruptions just like any other really depends on how it will erupt, violent or non-violent. When the shields volcanoes erupt it does like the rest it sends ash in the air and lava flows out. The lava flow on these volcanoes can be very interesting because they can just flow. They really make some pretty pictures. They usually donï¿½t have huge explosions that injure people but like all volcanoes they do damage to the environment. images.forbestraveler.com/.../volcano-01-g.jpg So as we can see all the different types of volcanoes are different but then again they alike in a lot of ways but the one thing that I learned is how there are different types of volcanoes and that they are not all the same. Types of Volcanoes Types of Volcanoes —Robert I. Tilling Source: U.S. Geological Survey Geologists generally group volcanoes into four main kinds—cinder cones, composite volcanoes, shield volcanoes, and lava domes. Cinder cones Cinder cones are the simplest type of volcano. They are built from particles and blobs of congealed lava ejected from a single vent.

As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as cinders around the vent to form a circular or oval cone. Most cinder cones have a bowl-shaped crater at the summit and rarely rise more than a thousand feet or so above their surroundings. Cinder cones are numerous in western North America as well as throughout other volcanic terrains of the world. In 1943 a cinder cone started growing on a farm near the village of Parícutin in Mexico. Explosive eruptions caused by gas rapidly expanding and escaping from molten lava formed cinders that fell back around the vent, building up the cone to a height of 1,200 feet. The last explosive eruption left a funnel-shaped crater at the top of the cone. After the excess gases had largely dissipated, the molten rock quietly poured out on the surrounding surface of the cone and moved downslope as lava flows. This order of events—eruption, formation of cone and crater, lava flow—is a common sequence in the formation of cinder cones.

During 9 years of activity, Parícutin built a prominent cone, covered about 100 square miles with ashes, and destroyed the town of San Juan. Geologists from many parts of the world studied Parícutin during its lifetime and learned a great deal about volcanism, its products, and the modification of a volcanic landform by erosion. Composite volcanoes Some of the Earth's grandest mountains are composite volcanoes—sometimes called stratovolcanoes. They are typically steep-sided, symmetrical cones of large dimension built of alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs and may rise as much as 8,000 feet above their bases. Some of the most conspicuous and beautiful mountains in the world are composite volcanoes, including Mount Fuji in Japan, Mount Cotopaxi in Ecuador, Mount Shasta in California, Mount Hood in Oregon, and Mount St. Helens and Mount Rainier in Washington. Most composite volcanoes have a crater at the summit which contains a central vent or a clustered group of vents. Lavas either flow through breaks in the crater wall or issue from fissures on the flanks of the cone.

Lava, solidified within the fissures, forms dikes that act as ribs which greatly strengthen the cone. The essential feature of a composite volcano is a conduit system through which magma from a reservoir deep in the Earth's crust rises to the surface. The volcano is built up by the accumulation of material erupted through the conduit and increases in size as lava, cinders, ash, etc., are added to its slopes. When a composite volcano becomes dormant, erosion begins to destroy the cone. As the cone is stripped away, the hardened magma filling the conduit (the volcanic plug) and fissures (the dikes) becomes exposed, and it too is slowly reduced by erosion. Finally, all that remains is the plug and dike complex projecting above the land surface—a telltale remnant of the vanished volcano. An interesting variation of a composite volcano can be seen at Crater Lake in Oregon. From what geologists can interpret of its past, a high volcano—called Mount Mazama- probably similar in appearance to present-day Mount Rainier was once located at this spot. Following a series of tremendous explosions about 6,800 years ago, the volcano lost its top.

Enormous volumes of volcanic ash and dust were expelled and swept down the slopes as ash flows and avalanches. These large-volume explosions rapidly drained the lava beneath the mountain and weakened the upper part. The top then collapsed to form a large depression, which later filled with water and is now completely occupied by beautiful Crater Lake. A last gasp of eruptions produced a small cinder cone, which rises above the water surface as Wizard Island near the rim of the lake. Depressions such as Crater Lake, formed by collapse of volcanoes, are known as calderas. They are usually large, steep-walled, basin-shaped depressions formed by the collapse of a large area over, and around, a volcanic vent or vents. Calderas range in form and size from roughly circular depressions 1 to 15 miles in diameter to huge elongated depressions as much as 60 miles long. Shield volcanoes Shield volcanoes, the third type of volcano, are built almost entirely of fluid lava flows. Flow after flow pours out in all directions from a central summit vent, or group of vents, building a broad, gently sloping cone of flat, domical shape, with a profile much like that of a warrior's shield.

They are built up slowly by the accretion of thousands of highly fluid lava flows called basalt lava that spread widely over great distances, and then cool as thin, gently dipping sheets. Lavas also commonly erupt from vents along fractures (rift zones) that develop on the flanks of the cone. Some of the largest volcanoes in the world are shield volcanoes. In northern California and Oregon, many shield volcanoes have diameters of 3 or 4 miles and heights of 1,500 to 2,000 feet. The Hawaiian Islands are composed of linear chains of these volcanoes including Kilauea and Mauna Loa on the island of Hawaii—two of the world's most active volcanoes. The floor of the ocean is more than 15,000 feet deep at the bases of the islands. As Mauna Loa, the largest of the shield volcanoes (and also the world's largest active volcano), projects 13,677 feet above sea level, its top is over 28,000 feet above the deep ocean floor.

In some eruptions, basaltic lava pours out quietly from long fissures instead of central vents and floods the surrounding countryside with lava flow upon lava flow, forming broad plateaus. Lava plateaus of this type can be seen in Iceland, southeastern Washington, eastern Oregon, and southern Idaho. Along the Snake River in Idaho, and the Columbia River in Washington and Oregon, these lava flows are beautifully exposed and measure more than a mile in total thickness. Lava domes Volcanic or lava domes are formed by relatively small, bulbous masses of lava too viscous to flow any great distance; consequently, on extrusion, the lava piles over and around its vent. A dome grows largely by expansion from within. As it grows its outer surface cools and hardens, then shatters, spilling loose fragments down its sides. Some domes form craggy knobs or spines over the volcanic vent, whereas others form short, steep-sided lava flows known as “coulees.” Volcanic domes commonly occur within the craters or on the flanks of large composite volcanoes.

The nearly circular Novarupta Dome that formed during the 1912 eruption of Katmai Volcano, Alaska, measures 800 feet across and 200 feet high. The internal structure of this dome—defined by layering of lava fanning upward and outward from the center—indicates that it grew largely by expansion from within. Mont Pelée in Martinique, Lesser Antilles, and Lassen Peak and Mono domes in California are examples of lava domes. An extremely destructive eruption accompanied the growth of a dome at Mont Pelée in 1902. The coastal town of St. Pierre, about 4 miles downslope to the south, was demolished and nearly 30,000 inhabitants were killed by an incandescent, high-velocity ash flow and associated hot gases and volcanic dust. Only two men survived; one because he was in a poorly ventilated, dungeon-like jail cell and the other who somehow made his way safely through the burning city. Three Types of Volcanoes: Cinder Cone, Composite, and Shield By Janice VanCleave A volcano is the mountain or hill formed by the accumulation of materials erupted through one or more openings in the Earth’s surface.

The pipe-like openings that connect the volcano’s crater (depression at the top) to the magma chamber (pool of molten rock deep within the Earth) are called volcanic vents. Volcanoes form because heat and pressure within Earth cause rock to melt . This molten rock, called magma, is less dense than the solid rock around it, so it is slowly forced toward the surface of Earth. Magma that reaches Earth’s surface through vents is called lava. A volcanic eruption is when lava, ash, debris, and/or gas is thrown out of a volcano. Some eruptions are very explosive while others are relatively quiet outpouring of bubbling lava or even gas. Some volcanoes on Earth are active (erupted within the last century), but most of them are dormant (inactive). Dormant volcanoes have not erupted in hundreds of years, but they could. Volcanoes that have not erupted in thousands of years are considered extinct and most likely will never again become active. There are more than 5,000 active underwater volcanoes and more than 800 active above-sea volcanoes in existence around the world. Different types of eruptions produce different kinds of volcanoes.

Following are three different types of volcanoes, for more information about these volcanoes and the different types of lava produced, see Exploring t he Environment: Volcanoes 1. Cinder Cone Volcanoes Explosive eruptions throw lava high into the air. The lava cools and hardens into different volcanic material called tephra (lava blasted into the air by a violent volcanic eruption that solidifies as it falls to the ground). Tephra comes in different sizes, including ash, cinders, and large rocks called volcanic bombs. A cinder cone volcano is formed by an explosive eruption in which tephra piles up into a steep-sided loosely packed cone. As the tephra fall back down around the vent, the heavier materials fall near the vent and the lighter weight materials are thrown farther away. This type of volcano usually has a rounded top with a small bowl-shaped crater (hollowed-out area at the top of a volcano). The upper parts of the volcano are steep with a more gently sloping base. There are many cinder cone volcanoes in the western United States, such as Sunset Crater in Arizona. These volcanoes are also found in many other parts of Earth, including the island of Java, in Indonesia.

2. Shield Volcanoes A shield volcano (a volcano composed of layers of solidified lava, a wide base, and a large, bowl-shaped opening at the top) is generally less steep and shorter than other types of volcanoes. It is made by repeated eruptions producing lava flows. The lava forming this volcano is relatively thin and flows away from the vent. As the lava cools, it becomes thicker, flows more slowly and finally becomes solid. Mauna Loa in Hawaii is one of the largest shield volcanoes. 3. Composite Volcano A composite volcano (cone-shaped volcano formed by alternating layers of solidified lava and rock particles) is a combination of a cinder cone and shield volcano that results from alternating eruptions of volcanic debris and lava. This type of volcano is likely to be the tallest and steepest volcano. Mount Rainier, in the state of Washington, is an example of a composite volcano. Cinder Cones | Volcano World | Oregon State University OREGON STATE UNIVERSITY Cinder Cones At the high-fountaining end of the spectrum are cinder cones.

Cinder cones can be quite large in Hawai'i; those on the summit of Mauna Kea (formed during gas-rich alkalic -stage eruptions) are a few hundred meters high, whereas those on Mauna Loa and Kilauea usually range between 20 and 100 m high. Pu'u 'O'o on the E rift of Kilauea, which formed between 1983 and 1986 is unusual in that it reached a height of 255 m above the surrounding surface (Heliker & Wright 1991). To the left is a photo of Pu'u 'O'o cinder cone, Kilauea, viewed toward the west. The prevailing right-to-left tradewind direction is obvious from the way that the plume is being blown. During the eruptions that formed Pu'u 'O'o, these same tradewinds built the cone much higher on the downwind side of the vent than the upwind side. Almost all the lava flows therefore came out of the upwind side (i.e. towards where the photo was taken). basalt .

Lava fountains are driven by expanding gas bubbles; the bubbles are trying to expand in all directions but the only way to relieve the pressure is up out the vent so fountains are usually directed relatively vertically. The Pu'u 'O'o fountains were at times up to 350 m high, and those during the early stages of the Mauna Ulu eruption were up to 500 m high. Because the pyroclasts are thrown so high, they cool before they land and don't stick together. Cinder cones are therefore composed of loose pyroclastics at the angle of (~33º). Right is an image of fountaining at Pu'u 'O'o, Kilauea (July 1985). These particular fountains were ~200 m high, and were sending short fast flows in many directions. In plan view, cinder cones tend to be roughly circular. They are usually formed later in an eruption when activity has localized to one or more discrete vents. If the precise location of the vent changes during an eruption, the cone loses its simple circular shape, and becomes more complex.

Roadcuts through most cinder cones expose very complicated crosscutting relationships relating to the different locations of the fountain centers. Photos of cinder cones on Mauna Kea (arrows), viewed from the summit of another cinder cone. The reddish color is common to cinder cones and occurs both during and soon after the associated eruption due to the combined efforts of moisture and oxidizing gases. The light blue line marks the Mauna Kea-Mauna Loa boundary. Note that one of the cones (yellow arrow) has been surrounded by (younger) Mauna Loa lavas. Cinder cones can also be distinctly asymmetric if there was a persistent wind blowing during the eruption and/or they form at the heads of major lava flows. In this second instance they are horseshoe-shaped (see below), with the lava flow issuing out of the open end because during the eruption any pyroclasts that landed on the flow were rafted away. A Mauna Kea cinder cone viewed from the air. A lava flow field (white outline) has issued from the base of the cone, giving the cone an asymmetric form. The flow spread almost all the way around the cone (white arrows).

Magenta lines mark the rims of older cinder cones nearby. Between the two extremes of spatter ramparts and cinder cones are all gradations. Some pyroclastic constructs consist of alternating layers of kilmer - Volcano Types Volcano Types The three main types of volcanoes There are three main types of volcanoes: shield, composite, and cinder-cone The Shield Volcano Shield volcano Shield volcanoes are large volcanoes that are built almost entirely of fluid lava flows. It has broad sloping sides and is usually surrounded by gently sloping hills in a circular or fan shaped pattern, that looks like a warrior's shield.The volcano is produced by the action of the gas with heat from the earth's core. This action melts rock turning it into magma. The pressure from the heat of the gas pushes the magma upwards till it explodes. Molten magma shoots upward from deep below the ocean floor and breaks through the plates to form shield volcanoes. Lava flows gently and continuously out of the central volcanic vent or group of vents. This lava is very runny, and can't be piled up into steep mounds. It gradually comes together and cools around the volcano.

The volcanoes are built up slowly by the accretion of thousands of highly fluid lava flows called basalt lava. The lava spread widely over great distances, then cools as thin gently dipping sheets. Lavas also erupt from vents along fractures (rift zones) that form on the flanks of the cone. Some of the largest volcanoes in the world are Shield volcanoes. Shield volcanoes may be produced by hot spots which lay far away from the edges of tectonic plates. Shields also occur along the mid-oceanic ridge, where sea floor spreading is in progress and along subduction related volcanic arcs. In northern California and Oregon, many Shield volcanoes have diameters of three or four miles and heights of 1,500 to 2,000 feet. A good example of a shield volcano is the Island of Hawaii. The Big Island is formed of five coalesced volcanoes of successively younger ages. The Hawaiian Islands are composed of linear chains of volcanoes including Kilauea and Mauna on the island of Hawaii. That is the shield volcano!

The Cinder-cone Volcano cinder cone volcano Cinder cone volcanoes are the most common kind of volcanoes.They are steep sided cones of basaltic fragments and are smaller and simpler than composite volcanoes. Streaming gases carry liquid lava blobs into the atmosphere that fall back to earth around a single vent to form the cone. The volcano forms when ash, cinders and bombs pile up around the vent to form a circular or oval cone.Cinders are melted volcanic rock that cooled and formed pebble-sized pieces when it was thrown out into the air. They are ejected from a single vent and accumulate around the vent when they fall back to earth.Bombs are melted volcanic rock that cooled and formed large pieces of rock when it was thrown out into the air before landing on the ground.Cinder cones are chiefly formed by Strombolian eruptions. They grow rapidly and soon reach their maximum size. Cinder cones can occur alone or in small to large groups or fields. Most have a bowl-shaped crater at the summit. The longer the eruption, the higher the cone. They rarely exceed 250 meters in height and 500 meters in diameter, although some may rise to as high as 650 meters or more.

If gas pressure drops, the final stage cinder cone construction may be a lava flow that breaks through the base of the cone. If a lot of water in the environment has access to the molten magma, their interaction may result in a maar volcano rather than a cinder cone. The shape of a cinder cone can be modified during its life. When the position of the vent alters, aligned twin cones develop. Nested, buried or breached cones are formed when the power of the eruption varies. A example of a cinder cone is Paricutin in Mexico. In Iceland, Surter I and Surter II cinder cone volcanoes. The Composite Volcano composite volcano Sometimes called Stratovolcanoes, Composite volcanoes form when runny lava escapes through a fissure and flows a long way. Composite volcanoes are tall cone-shaped mountains that are typically steeply-sided, symmetrical cones of large dimensions. The essential feature of a composite volcano is a conduit system through which magma from a reservoir deep in the earth's crust rises to the surface. The volcano is built up by the accumulation of material erupted through the conduit and increases in size as lava, cinders, ash etc. are added to its slopes.

Composite volcanoes erupt in different ways at different times. These volcanoes are built in layers by multiple eruptions, sometimes recurring over hundreds of thousands of years, sometimes over a few hundred. Andesite magma (the most common but not the only magma type), tends to form composite cones. During some eruptions, cinders, bombs and blocks form a mountain or add height to one that earlier volcanic eruptions had built. During other eruptions, lava flows cement these rocks together. Most composite volcanoes have a crater at the summit which contains a central vent or a clustered group of vents. Lava either flow through breaks in the crater wall or from fissures on the flanks of the cone. Lava, solidified within the fissures, form dikes that act as ribs which help to strengthen the cone. They may rise as much as 8,000 feet above their bases. Depending on the type of volcanic material it is composed of, some can grow to such heights that their slopes become unstable and are susceptible to collapse from the pull of gravity. When volcanic activity ceases, erosion begins to destroy the cone.

After thousands of years, the cone is stripped away and the hardened magma filling the conduit (the volcanic plug) and fissures (the dikes) become exposed, and it too is slowly reduced by erosion. Finally, all that is left is the plug or "volcanic neck" and dike complex projecting above the land surface. Some composite volcanoes occur in chains and are separated by several tens of kilometers. There are many composite volcano chains on earth, notably around the Pacific rim, known as the "Rim of Fire". Other examples of composite volcanoes and their locations are: Mount St. Helens - Washington State Mount Rainier - Washington State Three Types of Volcanoes: Cinder Cone, Shield and Composite | Sciencing Three Types of Volcanoes: Cinder Cone, Shield and Composite By Doug Bennett Jupiterimages/Photos.com/Getty Images There are three primary types of volcanoes, each with unique physical characteristics and eruptive natures. Composite volcanoes are explosive, towering giants. Shield volcanoes quietly produce broad, massive structures through lava flows. Cinder cone volcanoes are the smallest and simplest, but still pack a volcanic punch.

Composite Volcanoes Composite volcanoes, also referred to as stratovolcanoes, represent the classic shape most associated with a volcano. They tower over the landscape, rising to elevations of more than 10,000 feet. They are also the most common type of volcano on Earth, accounting for approximately 60 percent of the planet's volcanoes. They feature steep, upwardly concave sides and either a central vent or a cluster of vents at their summit. Their gas-rich andesite lava makes their eruptions explosive. As their name suggests, they are formed by alternating layers of hardened lava and pyroclastic material. In addition to their explosivity, composite eruptions typically plinian in nature, meaning they produce large eruptive columns that inject gases and particles high into the atmosphere. Shield Volcanoes Shield volcanoes are constructed almost entirely out of lava flows. Unlike composite volcanoes, shield volcanoes produce eruptions of very fluid basaltic lava. This lava flows out of vents in all directions, traveling long distances before solidifying. They are characterized by broad, gently sloping cones, resembling a soldier's convex shield.

They are commonly associated with a high magma supply rate, fueling a continuous flow of lava on the surface. Lacking any real explosivity, these ongoing eruptions take the form of lava fountains. Over time, shield volcanoes can become extremely large, producing islands in the middle of the ocean. Cinder Cone Volcanoes Cinder cone volcanoes are much smaller than either composite or shield volcanoes, typically rising no higher than 1,000 feet. They feature straight sides, with a steep slope of 30 to 40 degrees. They are typically circular, with a large bowl-shaped cater at the summit. Like shield volcanoes, cinder cone volcanoes eject basaltic lava. However, their lava is slightly thicker and contains more trapped gases. This gas results in small explosions that break the lava into smaller blobs, known as tephra. This tephra solidifies before it reaches the ground, producing piles of lava rocks around the vent. These cinder-like materials are where the volcanoes get their name. Because these volcanoes are constructed of loose tephra, they often produce lava flows from their base. Volcano Examples Mount St. Helens is an example of a composite volcano.

During the highly explosive 1980 eruption, the volcano experienced a large sector collapse that left a horseshoe-shaped crater. Mauna Loa, in Hawaii, is an example of a shield volcano. This volcano is the largest volcano on Earth, with a volume of 19,000 cubic miles and an area that covers 2,035 square miles. The Paricutin volcano, in Mexico, is an example of a cinder cone volcano. This volcano erupted out of a farmer's field in 1943, eventually covering 100 square miles in ash and 10 square miles in lava flows over a nine-year period. References Volcano Types Volcano Types Volcano Types The U.S. Geological Survey estimates that there are about 65 active volcanoes in the United States and its territories. The Dynamic maps viewer (shown at right) provides an interactive presentation of potentially active volcanoes in the 48 continguous states. Volcanoes are distinguished by their eruption style, composition, and structure. Volcanoes act differently and form differently because they are made up of different types of rocks and minerals. Below is a description of common volcano types that can be recognized as distinguishable land formations.

For more than 200 years keen observers have noted that some volcanic eruptions affect weather and climate. Scientists report that large eruptions at low latitudes can cause the greatest global climate change. Weaker eruptions send their eruptive materials only into the troposphere, where wind and rain quickly remove them. High latitude eruptions send their materials into only one hemisphere. Based on this information and the nature of different volcano types presented below, do you think that certain types of volcanoes are more likely to cause climate change when they erupt? See if you can answer this question as you investigate the relationship between volcanoes and climate change. Volcanoes have many shapes and sizes, but the following three types are most important: stratovolcanoes, shields, and supervolcanoes. Use the Dynamic map tool to find further illustrations of volcanoes described in this overview of volcano types. Stratovolcanoes (Composite Volcanoes) Many of Earth's most beautiful mountains are stratovolcanoes—also referred to as composite volcanoes. The stratovolcanoes are made up of layers of lava flows interlayed with sand- or gravel-like volcanic rock called cinders or volcanic ash.

These volcano land formations are typically 10-20 miles across and up to 10,000 or more feet tall. This type of volcano has steeper slopes of 6-10 degrees on its flanks and as much as a 30 degree slope near the top. Stratovolcanoes show interlayering of lava flows and typically up to 50 percent pyroclastic material, which is why they are sometimes called composite volcanoes. Pyroclastic flows are high-density mixtures of hot, dry rock fragments and hot gases that move away from the vent that erupted them at high speeds. They may result from the explosive eruption of molten or solid rock fragments, or both. They may also result from the nonexplosive eruption of lava when parts of dome or a thick lava flow collapses down a steep slope. Most pyroclastic flows consist of two distinguishable flowing mixtures: a basal flow of coarse fragments that moves along the ground and a turbulent cloud of ash that rises above the basal flow. Ash may fall from this cloud over a wide area downwind from the pyroclastic flow.

Referring to the images below, the diagram shows how a composite or stratovolcano is “built” on the inside, and the photograph represents an example of an actual stratovolcano. Image above at left: A schematic representation of the internal structue of a typical stratovolcano (composite volcano). Image source: USGS publications . Image above at right: Mayon, a stratovolcano in the Philippines. Image source: . Shield Volcanoes The second type may be familiar to you from news reports from Hawaii: the shield volcano. This type of volcano can be hundreds of miles across and 10,000 feet high. A shield volcano is characterized by gentle upper slopes (about 5 degrees) with somewhat steeper lower slopes (about 10 degrees). The shield volcanoes are almost entirely composed of relatively thin lava flows built up over a central vent. These features are illustrated in the shield volcano diagram shown below. Shield volcanoes have small amounts of pyroclastic material, most of which accumulates near the eruptive vents, resulting from fire fuming events. Thus, shield volcanoes typically form from nonexplosive eruptions of low viscosity basaltic magma.

The individual islands of the state of Hawaii are simply large shield volcanoes. Mauna Loa, a shield volcano on the "big" island of Hawaii, is the largest single mountain in the world, rising more than 30,000 feet above the ocean floor and reaching almost 100 miles across at its base. Shield volcanoes have low slopes and consist almost entirely of lavas. They almost always have large calderas at their summits. The graphic at left illustrates the internal structure of a typical shield volcano. Image source: Calderas: A Landform at the Summit of Shield and Stratovolcanoes Both strato/composite and shield volcanoes can lose their tops following a series of tremendous explosions. The change in these volcanoes' structure is visible as a large depression at the shield or stratovolcano summit. After enormous volumes of volcanic ash and dust are expelled and swept down the slopes as ash and avalanches, these large volume explosions rapidly drain in magna beneath the mountain and can no longer support the volcano top. The collapsing top forms a large depression in the landscape, which may later fill with water to form a lake.

Similarly, the tops of shield volcanoes collapse when magma erupts as lava flows, emptying the magma chambers. The steep-walled, basin-shaped depressions formed by the collapse of volcanoes are called calderas. Calderas by definition are larger than 1.5 miles in diameter and can range up to 15 miles wide or as huge elongated depressions as much as 60 miles long. The two images below show two very different caldera land formations. Image above at left: Crater Lake, Oregon; Wizard Island, a cinder cone, rises above the lake surface. Image source: USGS publications . Image above at right: This Ikonos image, taken on Jan. 14, 2003, shows Kilauea’s summit caldera, the surface of which is covered in fresh lava flows. The newer flows are dark, while the older flows pale as the iron in the lava oxidizes into rust. The oldest flow in the caldera is from 1882. The Halema`uma`u crater forms a pale circle in the southwest section of the caldera. As recently as 1924, the crater was filled with a molten lava lake.

Image source: NASA Earth Observatory . Supervolcanoes While ordinary volcanoes can kill thousands of people and destroy entire cities, scientists believe that a supervolcano explosion is big enough to affect everyone on the planet. Although they're called "super," most people would have trouble spotting a supervolcano before it erupts. The main feature of supervolcanoes is a large magma chamber, which is an underground reservoir filled with flowing, hot rock under huge pressures. Afer their eruption ash has been blown so far away that no mountain exists, and commonly the area is low and lake-filled. A supervolcanic eruption is rare. The last one occurred at Toba, Indonesia, about 74,000 years ago. Geologists think these eruptions take place about every 50,000 years. About 40 supervolcanoes are identified across the globe, but fortunately no supervolcano eruption has occured in the last 1,000 years. Yellowstone, located in Wyoming, is a dormant supervolcano, which means a major eruption could happen in the future.

The Yellowstone National Park lies within the Yellowstone Caldera, a collapse hat formed during a super eruption 640,000 years ago. Heat from magma beneath the caldera still fuels some 10,000 geothermal features (geysers and hot springs)—that's half of the world total. The map above at left of the Yellowstone supervolcano shows the lava flows. The flow is dated to be 72,000 years old and to have erupted as a single event. Other flows were likely formed from multiple eruptions. Photo credit: USGS/Yellowstone Volcano Observatory. The image above at right shows steam rising from Castle Geyser in Yellowstone National Park. Image source: Yellowstone National Park (file photo): Photograph by Mark Thiessen, National Geographic. Cinder Cone Volcanoes An easily recognized type of volcano is the cinder cone. As you might expect from the name, these volcanoes consist almost entirely of loose, grainy cinders consisting typically of basaltic and andesitic material and almost no lava. They are small volcanoes, usually only about a mile across and up to about 1,000 feet high.

They have very steep sides and usually have a small crater on top. Often cinder cones are classed as a major type of volcano. But cinder cones are much smaller than most shield, composite, and ash flow volcanoes. In fact, cinder cones occur on all of these larger volcano types. Image at left: A schematic representation of the internal structure of a typical cinder cone. Image source: USGS publications . Image at right: Cinder cone volcano near Veyo, Utah. Image source: . More Volcano Types Maars, lava domes, geysers, fumaroles, hot springs, and pateau basalts are also volcanic land forms caused by different geological processes that form them and control their activities once these different geophysical structures are formed. These and the other volcanic stuctures described above are characterized by the types of materials they are made of, which results from prior eruptive behavior of the volcano. Explore how geologists study and classify volcanic eruptions and landforms with these additional resources: The Volcano Hazards Program at USGS: Earth Observatory: Volcano Images and Features: Can You Recognize Types of Volcanoes?

What types of volcanoes are seen in this image of Russia’s Kamcharka Peninsula? Hint: Look closely. There are two stratovolcanoes, one shield volcano, and one volcano that appears to be formed from overlapping stratovolcanoes. View image with volcano types identified in the Volcanoes Featured Data section. This image was taken by an astronaut of the Expedition 25 crew from the International Space Station. Volcano Facts and Types of Volcanoes Volcano Facts and Types of Volcanoes By Mary Bagley, LiveScience Contributor | February 20, 2013 07:00pm ET MORE Close view of Stromboli Volcano erupting incandescent molten lava framgents. Credit: B. Chouet/USGS. A volcano is a vent or fissure in Earth's crust through which lava, ash, rock and gases erupt. A volcano is also a mountain formed by the accumulation of these eruptive products. Let's take a look at how volcanoes form: Earth's crust is 40 to 250 miles (64 to 402 kilometers) thick.

It is broken up into 14 major and 38 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 — where they move past, are pushed under, or move away from each other — magma, which is lighter than the surrounding solid rock, is often able to force its way up through cracks and fissures. Magma can explode from the vent, or it can flow out of the volcano like an overflowing cup. Magma that has erupted is called lava. [ Related: 50 Amazing Volcano Facts ] Principal types of volcanoes Cinder cone volcanoes (also called scoria cones) are the most common type of volcano and are the symmetrical cone shaped volcanoes we typically think of. They may occur as single volcanoes or as secondary volcanoes on the sides of stratovolcanoes or shield volcanoes. Airborne fragments of lava, called tephra, are ejected from a single vent. The lava cools rapidly and builds up around the vent, forming a crater at the summit.

Cinder cone volcanoes are fairly small, generally only about 300 feet (91 meters) tall and not rising more than 1,200 feet (366 meters). They can build up over short periods of a few months or years. Stratovolcanoes are also called composite volcanoes because they are built of layers of alternating lava flow, ash and blocks of unmelted stone. They are larger than cinder cones, rising up to 8,000 feet (2,438 meters). Stratovolcanoes result from a conduit system of vents leading from a magma reservoir beneath the surface. When dormant, they typically have steep concave sides that sweep together at the top around a relatively small crater. Stratovolcanoes erupt with great violence. Pressure builds in the magma chamber as gases, under immense heat and pressure, are dissolved in the liquid rock. When the magma reaches the conduits the pressure is released and the gases explode, like soda spewing out of a soda can that you shook up and opened suddenly. Because they form in a system of underground conduits, stratovolcanoes may blow out the sides of the cone as well as the summit crater.

Stratovolcanoes are considered the most violent eruptions. Mount St. Helens , in Washington state, is a stratovolcano that erupted on May 18, 1980. Approximately 230 square miles (596 square kilometers) of forest was completely obliterated and 57 people were killed. Ash was blown up into the atmosphere and fell over 11 states. Shield volcanoes are huge, gently sloping volcanoes built of very thin lava spreading out in all directions from a central vent. They have wide bases several miles in diameter with steeper middle slopes and a flatter summit. The gentle convex slopes give them an outline like a medieval knight’s shield. Eruptions are not generally explosive, more like liquid overflowing around the edges of a container. The world’s largest volcano, Mauna Loa in Hawaii, is a shield volcano. Mauna Loa is about 55,770 feet (17,000 meters) from its base beneath the ocean to the summit, which is 13,681 feet (4,170 meters) above sea level. It is also one of the Earth’s most active volcanoes and is carefully monitored.

The most recent eruption was in 1984. Lava domes are built up when the lava is too viscous to flow. A bubble or plug of cooling rock forms over a fissure. This cooler, thick lava usually rises near the end of an explosive eruption and lava domes often form within the craters of stratovolcanoes. Mount St. Helens has several well-defined lava domes inside the crater. Other volcanic landforms Besides the symmetry of well-known stratovolcanoes such as Mount Fuji in Japan and Kilimanjaro in Tanzania, volcanic activity is responsible for several other distinctive landforms. Calderas: A caldera is a bowl-shaped depression formed when a volcano collapses into the void left when its magma chamber is emptied; there are three types. The first type is a crater lake caldera. This is the result of a stratovolcano collapsing into its magma chamber during a violent eruption. Basaltic calderas have a concentric ring pattern resulting from a series of gradual collapses rather than a single event. They are often found at the summit of shield volcanoes such as the craters at the tops of Mauna Loa and Kilauea .

Resurgent calderas are the largest volcanic structures on Earth. They are the result of catastrophic eruptions that dwarf any eruptions ever recorded by human beings. Yellowstone caldera, sometimes called the “super volcano,” is one example. Volcanic plugs: When magma solidifies in the fissure of a volcano the hard dense rock may form a “neck” that remains when softer surrounding rock has been eroded away. This can result in dramatic landmarks such as Ship Rock in New Mexico, and Devil’s Tower in Wyoming. Lava Plateaus: Shield volcanoes may erupt along lines of fissures rather than a central vent spilling liquid lava in successive layers. Over time as these layers form broad plateaus such as the Columbia Plateau. These plateaus are often cut by deep canyons that expose the layers of rock. A fissure vent opened on Hawaii's Kilauea volcano. Credit: HVO/USGS Volcanoes in history A.D. 79: One of the most famous volcanoes is Mount Vesuvius, which sits along the Bay of Naples in southern Italy. It has erupted more than 50 times in the past 2,000 years. The A.D.

79 eruption, which buried Pompeii, made Vesuvius famous, but another eruption in 1631 killed some 4,000 people. 1669: In Sicily, Mount Etna sent a river of lava through the streets of Catania, killing some 20,000 people there and in the surrounding region. [ Video: Mount Etna's Dramatic New Eruption ] 1783: The eruption of Mount Skaptar in Iceland devastated farming and fishing, causing a famine that killed a fifth of the country's people. 1815:Whirlwinds and tsunamis from the eruption of Mount Tambora, on Sumbawa Island in Indonesia, killed 12,000 people. The volcano sent a cloud ejecta into the atmosphere that was more than four times the amount ejected by Mount Pinatubo in 1991. 1883: Another Indonesian volcano, Krakatoa, erupted in an explosion heard 3,000 miles away. Seventy-pound boulders landed on islands 50 miles away, and a 130-foot tsunami devastated hundreds of villages, including Java and Sumatra.

About 36,000 people died. Dust high in the atmosphere caused the Moon to appear blue, and sometimes green, for two years. 1902: Mount Pelée, on the island of Martinique, smothered the town of Saint-Pierre in deadly gas and hot ash, killing 29,933 of the 29,937 residents. 1980: Mount St. Helens in Washington state blew 1,300 feet off its top, killing 57 people and causing a midday darkness in towns 85 miles away. 1991: After 600 years of dormancy, Mount Pinatubo in the Philippines rumbled for days before erupting and killing about 750 people. Ash was more than 6 feet deep in a two-mile radius around the volcano, and buried a U.S. air base 15 miles away. Pinatubo's cloud of sulfuric acid, some 20 million tons of it, climbed to more than 12 miles in the stratosphere. Over the next several weeks, the cloud encircled the equator and spread to the poles, covering the entire planet.

The particles reflected sunlight and cooled the Earth by nearly a full degree Fahrenheit. Other significant U.S. volcanoes Lassen Peak, California: Erupted between 1914 and 1917, causing no deaths. Lassen is considered one of the most likely in the Cascade Range to erupt again. Long Valley, California: The Long Valley Caldera is a 10-by 20-mile depression in the Sierra Nevada Mountains caused by an eruption 700,000 years ago. A tremendous explosion spit out molten rock from 4 miles under the surface; afterward, the whole mess settled more than a mile down into the depression where the magma had been. Magma still feeds hot springs in the caldera. Earthquakes in 1980 marked the beginning of new activity that has included shifts in the position of hot springs and swarms of other small earthquakes. Geologists say it probably indicates that magma is again rising from below, and they suspect the area will erupt again. Mount Shasta, California: Last known eruption was in 1786. It is believed to erupt every 600 to 800 years.

Mountain is significant as the incredibly dominant visual element in the Northern California landscape. Kilauea and Muana Loa, Hawaii: Each tends to erupt every two or three years; eruptions are non-explosive, allowing these two volcanoes to be among the most studied active volcanoes in the world. Further reading:

Question: Cinder Cone, composite, and shield are all types of what?
Answer: Volcanoes