Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites

Details Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites

Dec 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995nugeo...9..609a&link_type=abstract

Nuclear Geophysics, Volume 9, Issue 6, p. 609-618.

Physics

Geophysics

7

Scientific paper

Meteorites, being the most ancient objects in the solar system, retain evidence of many events and processes which have played, perhaps, a crucial role in its formation. To derive and interpret correctly the available information, the history and evolution of the meteorites themselves must be studied thoroughly. Due to radiogenic and cosmogenic nuclides the chronology of meteorites can be retraced from the moment of solidification to their fall to Earth. A consideration of the properties and features of meteorites with different radiogenic and cosmic-ray ages of exposure makes it possible to locate key events in their evolution on a long term scale. Peculiarities in the formation mechanism of H- and L-chondrites have emerged. The genetic kindred of Antarctic and non-Antarctic chondrites has been established. A difference of terrestrial ages of the Antarctic H- and L-chondrites has been revealed. By using the depth distributions of cosmogenic radionuclides with different half-lives inside meteorites, the pre-atmospheric sizes of the latter for the different time periods can be determined, and hence the evolution of the meteorites in space can be retraced. As ascertained, only about 30% of chondrites undergo repeated collisions, and small chondrites have, presumably, rather low exposure ages, i.e. shorter lifetimes in interplanetary space. An elaborated isotopic approach provides estimates of the extent of meteorite orbits, so that the aphelion of orbits of more than 100 chondrites have been determined. According to the results, the aphelion of ordinary chondrites are mainly in the range of 2-2.5 AU from the sun, which proves the origin of the chondrites from the Mars or Apollo families of asteroids. A consideration of properties and features of the chondrites with various orbits makes it possible to locate the main events in their life on a space scale. Any essential chemical or petrological distinction of chondrites with different orbits (within each type) has not been observed. However, some random factors, which influence what meteorites can undergo in space, are most operative between 2 and 2.5 AU from the sun.

Affiliated with

Also associated with

No associations

Rating

Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cosmogenic nuclide evidence on ages, sizes and orbits of meteorites will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1563043