|Hawaii Volcanoes Photo Gallery|
Top: Fast moving channel of `a`a behind the leading edge of the flow.
Photographs by D.A. Swanson, USGS
photo and caption credit
U.S. Department of Interior, U.S. Geological Survey
Bottom: Leading edge of the same `a`a flow; pieces of broken crust are tumbling from the front, exposing the molten interior.
This `a`a flow originated from a breakout of lava tube 200-300 m upslope on Pulama pali. The breakout initially formed a pahoehoe flow. As the pahoehoe sped down the steep slope of the pali, it transformed into `a`a. When the photographs were taken, the front of the `a`a was advancing at a rate of 1 m per minute or faster, burning and bulldozing its way through the bordering `ohi`a forest.