Pāhoehoe

Pāhoehoe

A pāhoehoe flow typically advances as a series of small lobes and toes that continually break out from a cooled crust. It also forms where the minimal heat loss maintains low viscosity. The surface texture of pāhoehoe flows varies widely, displaying all kinds of bizarre shapes often referred to as lava sculpture. With increasing distance from the source, pāhoehoe flows may change into ʻaʻā flows in response to heat loss and consequent increase in viscosity. Pahoehoe lavas typically have a temperature of 1100 to 1200 °C.

The rounded texture makes pāhoehoe a poor radar reflector, and is difficult to see from an orbiting satellite (dark on Magellan picture).

Pāhoehoe (also spelled pahoehoe, pronounced from Hawaiian, meaning "smooth, unbroken lava") is lava that has a smooth, billowy, undulating, or ropy surface. These surface features are due to the movement of very fluid lava under a congealing surface crust. The Hawaiian word was introduced as a technical term in geology by calrecnce dutton.