shergottite
Shergottites are igneous rocks of volcanic or plutonic (formed deep under the surface) origin. They resemble terrestrial rocks more closely than do the members of any other achondrite group. All have exceptionally young crystallization ages of 150 to 200 million years, and usually show signs of severe shock metamorphism. Typically, the plagioclase in shergottites has been converted to maskelynite, a glass that is produced when plagioclase is subjected to high shock pressures. The maskelynite was probably formed as a result of the impacts that ejected the shergottites from the Martian surface. Related categories MARS TOPICS METEORS AND METEORITES ASTROBIOLOGY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |