Page 96 - Super Earth Encyclopedia

AT A GLANCE LOCATION Yellowstone National Park, CALDERA SIZE 1,500 sq miles (3,900 sq km) FORMATION Collapse into magma chamber emptied by a huge volcanic eruption MAIN FEATURES Geysers, hot springs, fumaroles, and minor earthquakes A shallow magma chamber beneath the caldera heats groundwater. This water erupts as hot springs and geysers. The lower magma chamber contains a mixture of hot, semi-molten, spongy rock, and liquid magma.

• Wyoming • • •

This entire area of Yellowstone National Park is 3,472 square miles (8,991 sq km).

lies a simmering supervolcano—a gigantic mass of molten rock that could erupt with
atmosphere with volcanic dust. As the magma chamber emptied, the ground above
collapsed into it, forming a broad depression known as the Yellowstone caldera.
enough force to cause global chaos. It has done so in the distant past, filling the

Deep beneath the spectacular wilderness of Yellowstone National Park

Today, this has many hot springs and geysers, fuelled by the heat below.

YELLOWSTONE CALDERA

Parts of the caldera floor are being forced up into shallow domes by the swelling magma below.
SUPERVOLCANO

Yellowstone Lake lies in the lowest part of the caldera at the heart of Yellowstone National Park. Sleeping giant Yellowstone lies above a hotspot in Earth’s mantle—a huge, mobile mass of extra-hot rock that rises from near the planet’s core. This mantle plume is solid, but flows very slowly. At the top, reduced pressure allows some of the hot rock to melt and flow into a magma chamber deep in Earth’s crust below Yellowstone. This feeds a shallower magma chamber that lies

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