Impactite
Encyclopedia
Impactite is an informal term describing a rock
created or modified by the impact of a meteorite
. The term encompasses shock-metamorphosed
target rocks, melts (suevite
s) and mixtures of the two, as well as sedimentary rocks with significant impact-derived components (shocked mineral grains, tektites, anomalous geochemical signatures, etc.).
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...
created or modified by the impact of a meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
. The term encompasses shock-metamorphosed
Shock metamorphism
Shock metamorphism or impact metamorphism describes the effects of shock-wave related deformation and heating during impact events. The formation of similar features during explosive volcanism is generally discounted due to the lack of metamorphic effects unequivocally associated with explosions...
target rocks, melts (suevite
Suevite
Suevite is a rock consisting partly of melted material, typically forming a breccia containing glass and crystal or lithic fragments, formed during an impact event...
s) and mixtures of the two, as well as sedimentary rocks with significant impact-derived components (shocked mineral grains, tektites, anomalous geochemical signatures, etc.).
Some localities
- Nördlinger RiesNördlinger RiesThe Nördlinger Ries is a large circular depression in western Bavaria, Germany, located north of the Danube in the district of Donau-Ries. The city of Nördlingen is located about southwest of the centre of the depression....
crater - Rochechouart craterRochechouart craterRochechouart is an impact crater in France.The crater diameter is still under study but is expected to be about . Its most recent age estimate is 201 ±2 million years ago, placing it close to Triassic-Jurassic boundary. Since then the crater has been deeply eroded, and no trace of its original...
- Wabar impact siteWabar cratersThe Wabar craters are impact craters brought to the attention of Western scholars by an explorer searching for the legendary city of Ubar in Arabia.-1932 Philby:...
- Darwin glassDarwin GlassDarwin glass is a natural glass found south of Queenstown in West Coast, Tasmania. It takes its name from Mount Darwin in the West Coast Range, where it was first reported, and later gave its name to Darwin Crater, a probable impact crater, and the inferred source of the glass.-Occurrence:Fragments...
from Tasmania - Alamo bolide impactAlamo bolide impactThe Alamo bolide impact occurred 367 million years ago, when one or more hypervelocity objects from space slammed into shallow marine waters at a site that is now the Devonian Guilmette Formation of the Worthington Mountains and Schell Creek Range of southeastern Nevada; the event is named for...
(Late Devonian) of Nevada - CharlevoixCharlevoixThe Charlevoix region, located in Quebec, includes parts of the north shore of the Saint Lawrence River and the Laurentian Mountains region of the Canadian Shield...
in the province of Québec, Canada - Neugrund craterNeugrund craterNeugrund is a meteorite crater in Estonia. It is in diameter and is estimated to have been formed 470 million years ago in the Ordovician period. The crater lies at the bottom of the sea and is not exposed at the surface. However, boulders of gneissic breccia found on the coast of Osmussaar, a...