- Pit crater
A pit crater (also called a subsidence crater) is a depression formed by a sinking of the ground surface lying above a void or empty chamber, rather than by the
eruption of avolcano orlava vent. [cite web
url=http://volcano.und.edu/vwdocs/glossary.html
title=Volcanic and Geologic Terms
publisher=volcano.und.edu
accessdate=2008-04-12
last=
first=] It is often found in chains or troughs, which may merge into a linear alignment and usually lack an elevated rim. They also lack ejected deposits and thelava flow s that are associated withimpact crater s.As distinct from
meteor crater s, these craters are not formed from the clashing of bodies or projectiles from space.cite web
url=http://www.agu.org/pubs/crossref/2004/2004JE002240.shtml
title=Distribution, morphology, and origins of Martian pit crater chains
publisher=www.agu.org
accessdate=2008-04-12
last=
first=] Rather, they can be formed by alava explosion from a bottled upvolcano , the explosion leaving a shallowcaldera , or the ceiling over a void may not be solid enough to prevent the collapse of the overlying material. A pit crater also could result from the collapse oflava tube s,dike swarm s, or from collapsedmagma chamber s under loose material.cite book
last =The Diagram Group
first =David Lambert &
authorlink =
title = The Field Guide to Geology (Updated Ed.)
publisher = Facts on File, Inc.
date =1998
location =MY
pages =pp 44–45, 94–95
id =
isbn = 0-87842-334-3 ]The process happens frequently on
Mars but rarely onEarth . Hawaii is known for its volcanoes and pit craters. In 1868 an eyewitness saw more than two-thirds of the basin of Kilauea cave in and fill with alava lake . This process happened repeatedly. The modern Halema'uma'u Shield began growing and then collapsed into a deep funnel-shaped pit. This pit filled with lava and for 19 years burned continuously, becoming famous as the Hawaiian Fire Pit. In 1924 the lava lake emptied when the walls of the crater cracked and collapsed and filled with water that turned to steam. After a week and a half Halema'uma'u had widened and was 1,700 feet deep. Rocks that were blasted away from the crater can still be seen on the caldera floor.cite book
last =Donald W. Hyndman
first =Richard W. Hazlett &
authorlink =
title = Roadside Geology Of Hawai'i
publisher = Mountain Press Publishing
date =2005
location =Missoula, MN
pages =pp 22–23, 68–70, 72–73, 75, 80–82
id =
isbn = 0-87842-334-3 ]Footnotes
External links
* [https://www.uwec.edu/jolhm/Hawaii2005/Day3/HIwebsite/FS12.htm Halema'uma'u Crater]
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