Shield Volcano


Types of Volcanoes


One of the reasons that volcanoes are so fascinating is that you could find many different types of volcanoes. The volcanoes can be classified according to their shape, size, dome and even their location. There are other aspects that can also affect the classification of the types of volcanoes found on Earth like the structure of the volcano and if there are any vents or fissure that allow air. Some of those volcanoes are not known for their features but for the type of eruption they will have. Here are some of the volcano types that you will find and how to recognize them.

Fissure Vent

A fissure vent or volcanic fissure is a linear vent on the ground of a volcanic area where lava can erupt from. Usually the lava eruption from a fissure vent will not be an explosive one. The size of the vent is not something that is standard as some can be as small as a few meters wide, but the length can be several kilometers. These types of volcanoes can be very difficult to recognize unless you know that you are standing over it as it is mostly flat. There is no central caldera to these volcanoes and the fissures can be covered up when lava cools down.

Shield Volcano

Shield volcanoes are types of volcanoes which are formed due to several lava flows which eventually give them the shape of a warrior’s shield. These volcanoes are not the tall mountains that you expect to see when you think of a volcano, but rather low profile structures that look more like a small hill than a full mountain. The summit of these volcanoes is usually flat whole the width can be very big. Usually the height of a shield volcano will be just 1/20th of the total volcano’s width.

Lava Dome

A lava dome is a circular volcanic formation which happens due to the viscous lava slow movement. Its shape happens because of the viscosity of the material coming out of the volcano. The domes are very common in volcanic areas and while they are not the awesome show that a volcanic explosion would be it is still something to be admired. Another reason that they form is that there usually is not enough pressure for an massive explosion which means that there could be some sort of vent allowing the gases to escape the structure.


A stratovolcano is recognized mostly because of its shape and size. These types of volcanoes tend to be very tall and conical. Their composition will also help you recognize them as they are made of a hardened lava layer, volcanic ash and tephra. Their profile is steep and the lava that shoots out of these types of volcanoes tends to be very viscous and because of that the cooling of the lava will be done quicker than in other volcanoes meaning that the flow will not get too far away. It is not rare for the stratovolcano to be very tall with a lot of them exceeding 2500 meters.

Because of their shape and height a lot of these types of volcanoes have become very famous. One of the most recognized volcanoes that fall under this category is Mount Fuji in Japan. Mount Vesuvius is another highly recognized and extremely famous stratovolcano. Stromboli is another very famous active volcano that falls under the same category. These volcanoes are famous not only because of their shape but also because of the damage they have caused in the past and the possibility that they will cause severe damage in the future as well.


The supervolcano is out of all types of volcanoes the one that could cause the most damage. Some scientists predict that an eruption of a supervolcano today could in fact end life in the planet due to the massiveness of the eruption. The problem with that prediction is that there have been such eruptions in the past and there will be another one in the future. The last eruption of the Yellowstone supervolcano is believed to have caused the last ice age and that killed several species. If that were to happen today it could mean a world-wide food shortage that would lead to the starvation of those that survived the eruption and the ash.

The supervolcanoes are ranked by the Volcano Eruption Index and they usually fall under the VEI 7 and the VEI 8 Rankings. There have been a total of VEI 8 eruptions in the history of the planet, five of which have taken place in the United States area. There are currently six famous supervolcanoes in the world, and they are the Yellowstone Caldera in the US, The Long Valley Caldera in the US, the Valles Caldera also in the US, Lake Toba in Indonesia, the Taupo Caldera in New Zealand and the Aira Caldera in Japan.

Submarine Volcano

A submarine volcano is a fissure which can be found under water from which there can be an eruption of magma. It has been calculated that up to 75% of the magma output each year comes from these types of volcanoes. Most of these volcanoes are found close to areas where tectonic movement takes place. Those areas are called ocean ridges. Most of these volcanoes are very deep in the ocean, but there are a few of them which can also be found very close to the surface of the water. Because of the depth of some submarine volcanoes they can be very hard to detect.

Subglacial Volcano

A subglacial volcano or glaciovolcano is one that takes place under the surface of the glacier and in some cases under the ice sheet. These types of volcanoes will quickly create a lake due to the fact that the hot lava will melt the ice very fast. The places with the most subglacial volcanoes are Antarctica and Iceland, but they can also be found in Yukon and British Columbia in Canada.

The subglacial volcano is very similar to the submarine volcano because they will both cool the magma quickly creating very similar reactions on the surface. The areas close to a subglacial volcano can be affected by flooding because of the displacement of the water during the eruption and the additional volcanic material which is released. Theoretically an eruption that was massive enough could cause a tsunami to take place.

Mud Volcano

A mud volcano is a very different thing from a regular volcano, but the concept can be similar. These types of volcanoes are also called mud domes and they form by pressure from gases and liquids. The hot water and the mud mix with surface deposits and that is what pushes the surface up. Currently there are 1100 such structures identified, but more are always a possibility especially in subduction zones. Generally these volcanoes will indicate that there may be a petroleum deposit or that there is a volcano nearby.

If a volcano is close to a mud volcano then most of the gas leaving the structure will be Helium, while those that do not have a volcano nearby will emit mostly methane. Current estimates that would take into account the mud volcanoes not found yet, would have the total amount at over 10,000.


Types Of Volcanoes Related Articles

Shield Volcano Facts


A shield volcano resembles the appearance of a Hawaiian warrior’s shield in that they have a low-angle profile. In almost all cases the comparison to a shield is done because the width of these volcanoes is typically around 20 times the size of their height. Despite this, they can vary greatly in terms of size with some having small diameters of a few kilometers while others can be over 95 kilometers. Some located in Hawaii reaching an altitude of 8,000 meters above the sea floor, which is 12,000 meters above their base. In fact, some of the largest volcanoes you will find on the planet are actually shield volcanoes, with Mauna Loa, located on Big Island in Hawaii, being the largest of this type.


A shield volcano is most likely to form during a lava flow of fluid basaltic material, usually those that flow down from either a flank fissure system or the summit itself. The most common type of shield volcano is those that form during one long-term eruption. Some shield volcanoes, however, are pyroclastic shields meaning that their low-angle slopes have been formed from the accumulation of fragmented material over the course of several eruptions.

Because of the variety of formation, you will see slightly different shapes in the various shield volcanoes around the world. The ones in Iceland, for example, are generally much smaller in size and almost perfectly symmetrical while those found in Hawaii are much larger (think of Mauna Loa) and elongated. The shields found on the Galapagos Islands are different from both of these, having flat tops, steep middle slopes and deep calderas at the summit. These differences not only show variations in formation but also in the eruption types generally found in the region.


Although the type of eruptions found in a shield volcano can vary slightly, most experience Hawaiian eruptions. These eruptions will usually have ground flows of lava that is capable of traveling great distances. Because the flows travel a longer distance, the individual sheets of lava are generally thinner. These longer lava flows from the eruptions are what gives the shied volcano their distinctive shape.

Hawaiian Volcanoes

Hawaii is home to a great deal of the planet’s shield volcanoes as the Pacific Plate and the Hawaii hotspot have combined to form a large chain of various volcanoes of all types. This chain includes more than 43 major volcanoes, including Mauna Loa. As mentioned earlier, Mauna Loa is the largest shield volcano. It is also Hawaii’s highest volcano, reaching 4,170 meters above sea level in addition to traveling 13 kilometers down below the waterline. This volcano has most likely been eruption for over 700,000 years and the most recent eruption took place in 1984.

Mauna Kea is another shield volcano found in Hawaii and it has an altitude 4,205 meters above sea level and from its base below sea level it is 10,200 meters. This means that although Mauna Kea has a higher elevation than Mauna Loa, its total height is smaller. Mauna Kea is probably around a million years old, attributing to its steeper and smoother profile. Despite this, this shield volcano has experienced several explosive eruptions late in its life which created several cinder cones on its summit.

Another one of Hawaii’s shield volcanoes is Kilauea which is in fact the most active of the island’s volcanoes. This volcano is only between 300,000 and 600,000 years old, making it one of the youngest in the area. At first scientists actually thought Kilauea was part of Mauna Loa; however they have since discovered that it acts independently. Interestingly enough, Kilauea’s current eruption began on January 3, 1983, meaning it has been going on for 30 years to date.


Another place that you can find multiple shield volcanoes is in Iceland. The shield volcanoes found there usually range from 5,000 to 10,000 years old. These volcanoes are also usually smaller than those in other locations and are generally symmetrical and their eruptions usually occur from their summit calderas.

Galapagos Volcanoes

Another area with a great deal of shield volcanoes is the Galapagos Islands, with the volcanoes ranging from 700,000 to 4.2 million years old. Several of the islands are in fact shield volcanoes, such as Fernandina. This shield volcano has steep upper flanks but low-angle lower flanks. It has been currently erupting since April of 2009.

In terms of composition, the lava flows found in the Galapagos Islands are very similar to those in Hawaii although unlike other sets of volcanoes formed by one hotspot, they do not create a line.

Other Volcanoes

In the Auckland volcanic field in New Zealand you can find Rangitoto which actually forms its own island with a width of 5.5 kilometers. This volcano erupted around 550 years ago. In the United States, you can find the Belknap volcano in the Cascade Range in Oregon in addition to the Newberry volcano which takes up around 1600 square kilometers of land.


Shield Volcano Related Articles