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Photo glossary of volcano terms

Photo: ropy pahoehoe, Kilauea Volcano, Hawaii

Photograph by T.N. Mattox
on 11 June 1995

Close view of ropy texture forming on the surface of a pahoehoe flow at Kilauea Volcano, Hawai`i.

Ropy pahoehoe
Ropy pahoehoe is the most common surface texture of pahoehoe flows. The numerous folds and wrinkles ("ropes") that are characteristic of ropy pahoehoe form when the thin, partially solidified crust of a flow is slowed or halted (for example, if the crust encounters an obstruction or slower-moving crust). Because lava beneath the crust continues to move forward, it tends to drag the crust along. The crust then behaves like an accordian that is squeezed together--the crust is flexible enough to develop wrinkles or a series of small ridges and troughs as it is compressed and driven forward.

Related photo glossary terms:

 

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U.S. Department of the Interior, U.S. Geological Survey, Menlo Park, California, USA
URL http://volcanoes.usgs.gov/Products/Pglossary/pahoehoe_ropy.html
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Last modification: Monday, 04-Sep-2000 22:44:33 EDT (SRB)