• An example of pahoehoe lava texture at the base of Hawaii's Mauna Kea volcano. (Photo: Alexandra Pope)

Pahoehoe

[pah-hoh-ey-hoh-ey]
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Definition
A form of lava flow of basaltic rock, usually dark-coloured with a smooth or rippled surface.

Origin
Hawaiian, meaning "smooth, unbroken lava." American geologist Clarence Dutton introduced the Hawaiian word as a technical term in geology.

Example
Pahoehoe lava is one of two main forms of lava flow that come from Hawaiian volcanoes. It is characterized by its appearance, which can be described as smooth, ropey, or undulating. These surface features are caused by the continued movement of very fluid lava underneath a cooling crust.

The other main form of lava found in Hawaii is a'a, which is rough and jagged.

An example of a'a lava texture at the base of Hawaii's Mauna Kea volcano. (Photo: Alexandra Pope)