Volcanic plateau

A volcanic plateau is a raised area of land made by volcanic activity. It forms when many eruptions pour out thick layers of lava or ash over a large region. These eruptions happen many times over millions of years, building up the land slowly.

There are two main kinds of volcanic plateaus. One is called a lava plateau, where rivers of lava flow and harden in layers. The other is a pyroclastic plateau, made from pieces of rock and ash thrown into the air during eruptions. Both types change the shape of the Earth and create unique landscapes.

These plateaus are important because they tell us about the history of volcanoes and how they shape the world. They also often hold valuable resources, like minerals, that people use. Studying them helps scientists understand how volcanoes work and how landscapes change over time.

Volcanic plateaus are not the same as oceanic plateaus, which are found under the sea.

Lava plateau

Lava plateaus are created when very fluid basaltic lava flows during many quiet eruptions. These eruptions are quiet because the lava is smooth and has few trapped gases. The lava can flow out from long cracks called fissures or rifts, or from big eruptions from many places. Over time, many layers of lava cover the land and form a flat area called a plateau. These plateaus can include lava fields, small hill-like cinder cones, and big shield volcanoes, along with other volcanic landforms.

One example is the huge Level Mountain shield volcano in northern British Columbia, Canada, covering an area of 1,800 km² (690 mi²). There are also large lava plateaus under the ocean, like the Ontong Java Plateau, and ones on land, such as the Columbia River Plateau.

Pyroclastic plateau

Pyroclastic plateaus are created by huge flows of volcanic material. They are made from rocks like volcanic ash that have been turned into solid layers. These plateaus are also known as ignimbrite plateaus.

One example is the Shirasu-Daichi in southern Kyūshū, Japan, and another is the North Island Volcanic Plateau in New Zealand.