BackgroundHell's Half Acre consists of a low basaltic lava shield with predominantly pahoehoe lava. Most eruptions took place from a 3-km-long, NW-SE trending vent system at the NW part of the field.
The summit vent area contains an irregular, elongate 0.8 x 0.3 km wide central caldera which contained a lava lake. There are about 10 circular pit craters on the lava lake and 2 prominent lava tube systems near the summit.
2 major lava flows, each about 5 km wide and 10 km long, extend to the south and SW along the flood plain of the Snake River and surround Morgans Pasture, a large kipuka (island spared by the lava flows). Interstate 15 highway crosses the SE margin of the lava field SW of the city of Idaho Falls.
See also: Sentinel hub | Landsat 8 | NASA FIRMS