What are the Different Types of Volcanoes?

There are four different types of volcanoes. A volcano is categorized both by formation and appearance. Different types of volcanoes also indicate the types of expected eruptions. The different types of volcanoes are: composite (or stratovolcanoes), shield, cinder cones and spatter cones. Throughout the world, one can see pictures of the four types of volcanoes, each type indicative of the active underground world we often view as static.

Layers, or strata, of rock and lava form the composite or stratovolcanoes. These volcanoes come in a number of shapes. A composite volcano like Mt. Rainier resembles a helmet. The sides of this type of volcano are usually steep, some reaching a pointy peek at the top. Mt. St. Helens, also in Washington, and Mt. Shasta in Northern California are both composites. As well, the recognizable Mt. Fuji in Japan is one of the largest composites in the world.

The composite volcano, when dormant, is generally a beautiful and impressive mountain. However, eruptions are particularly intense. As magma rises to the eruption point, it tends to get clogged due to high viscosity. The pressure needed to force the magma out of the volcano is huge, and the result is an explosion of both rock and lava. It is quite dangerous to witness such an eruption up close.

Shield volcanoes are also enormous. However, they differ from the stratovolcanoes since they are made of numerous layers of flowing lava. Hot spots may occur far from the central vent of the volcano.

Shields erupt frequently, but tend not to be highly explosive. These are some of the best volcano eruptions to witness at a relatively close, but still safe, range, since lava spray is uncommon. Both Mauna Loa and Kilauea in Hawaii are examples of the shield volcano. Shields also form on the ocean floor, gradually building height through a steady stream of magma.

Cinder cones are likewise relatively gentle in eruption. They tend to occur in mountain ranges with other types of volcanoes. A central vent forms a volcano made up of lava fragments. Cinders grow quickly but tend not to exceed about 800 feet (243.84m) in height. Occasionally, cinders form on ground with no known history of volcanic activity. In 1934, Paricutín erupted out of a Mexican cornfield and in approximately five days, grew to 300 feet (91.44m) tall.

Puʻu ʻŌʻō, pronounced poo-oo, is a Hawaiian spatter cone that has produced a continuous flow of lava since 1983. Occasional eruptions have been as high as 1500 feet (457.2m). The lava flow tends to be low in viscosity, and readily moves down the cone to cover the surrounding area. The Hawaiian volcano has caused the loss of a great deal of usable land and roads due to the constant flow. The lava tends to come down from the initial eruption in spattered formations, making it dangerous to come too close. While restricting access to some of the highways, Puʻu ʻŌʻō has added 544 acres of land to Hawaii’s main island.

One further classification of volcanoes is when geologists refer to a volcano as complex. A complex volcano can be combinations of any of the above volcanoes, but are primarily classified by the fact that they have at least two vents, often erupting in quite different ways.

There are four primary types of volcanoes: shield, cinder cone, composite (or stratovolcano), and lava dome. Shield volcanoes, like those in Hawaii, have gentle slopes and are formed by low-viscosity lava. Cinder cone volcanoes are small, steeply sloped, and erupt explosively. Composite volcanoes, such as Mount St. Helens, are characterized by a combination of explosive activity and lava flows. Lava domes are formed by viscous lava that piles up near the vent.

Shield volcanoes have broad, gently sloping sides formed by the flow of low-viscosity lava over great distances. In contrast, composite volcanoes have steeper profiles and are built from alternating layers of lava flows, volcanic ash, and other debris. Composite volcanoes tend to have more violent eruptions due to the higher viscosity of their magma compared to the fluid lava of shield volcanoes.

Composite volcanoes, also known as stratovolcanoes, are typically the most explosive. Their eruptions can be highly destructive due to the combination of explosive release of gases, pyroclastic flows, and the emission of thick, viscous lava. The eruption of Mount Tambora in 1815, a composite volcano, is one of the most powerful in recorded history.

Yes, the eruption style is often indicative of the type of volcano. Shield volcanoes usually have effusive eruptions, where lava flows out gently. Cinder cone volcanoes have more explosive eruptions, ejecting ash and lapilli. Composite volcanoes can have both explosive eruptions and effusive lava flows. Lava domes are typically associated with the extrusion of viscous lava.

The largest type of volcano on Earth is the shield volcano. These volcanoes can cover vast areas with their low-angle slopes. Mauna Loa in Hawaii is an example and is considered the largest volcano on Earth by volume and area covered. It spans over 5,271 square kilometers and rises more than 4,169 meters above sea level.

Not all volcanoes are cone-shaped. While cinder cone and composite volcanoes typically have a conical profile, shield volcanoes have a much flatter dome-like shape due to the fluidity of their lava. Lava domes can also vary in shape, often forming bulbous or spiny protrusions rather than neat cones.