pahoehoe
Quick Summary
Pahoehoe is a type of basaltic lava characterized by a smooth, often shiny, and billowy surface. This highly fluid lava spreads in thin sheets and forms ropy folds as it continues to flow beneath a hardening crust. The surface of pahoehoe lava flows can appear gently undulating or broadly hummocky, with liquid lava beneath the surface wrinkling it into tapestry-like folds that resemble twisted rope. These flows are typically fed internally by streams of liquid lava. In contrast, 'a'a lava has a rougher surface composed of irregular fragments. Pahoehoe and 'a'a lava can originate from the same eruption and a flow can change from pahoehoe to 'a'a as it moves downslope.12
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lava…known by the Hawaiian names pahoehoe and aa (or a’a). Pahoehoe lava flows are characterized by smooth, gently undulating, or broadly hummocky surfaces. The liquid lava flowing beneath a thin, still-plastic crust drags and wrinkles it into tapestry-like folds and rolls resembling twisted rope. Pahoehoe lava flows are fed almost…
Read More…known by the Hawaiian names pahoehoe and aa (or a’a). Pahoehoe lava flows are characterized by smooth, gently undulating, or broadly hummocky surfaces. The liquid lava flowing beneath a thin, still-plastic crust drags and wrinkles it into tapestry-like folds and rolls resembling twisted rope. Pahoehoe lava flows are fed almost…
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volcanoLava flows…world by their Hawaiian names: pahoehoe, a more fluid flow with a smooth to ropy surface; and aa (or a’a), a more viscous flow whose surface is covered by thick, jumbled piles of loose, sharp blocks. Both types have the same chemical composition; the difference seems to be in the…
Read More…world by their Hawaiian names: pahoehoe, a more fluid flow with a smooth to ropy surface; and aa (or a’a), a more viscous flow whose surface is covered by thick, jumbled piles of loose, sharp blocks. Both types have the same chemical composition; the difference seems to be in the…
Read More- volcanoDeterminants of size and shape
These flows, known as pahoehoe, tend to flow farther than the cooler aa flows of the same chemical composition that have rough, broken surfaces. (See the section Lava flows.)
Read MoreThese flows, known as pahoehoe, tend to flow farther than the cooler aa flows of the same chemical composition that have rough, broken surfaces. (See the section Lava flows.)
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