Physics
Scientific paper
Nov 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995natur.378...41h&link_type=abstract
Nature, Volume 378, Issue 6552, pp. 41-44 (1995).
Physics
31
Scientific paper
SHOCK-PRODUCED diamond and lonsdaleite (the hexagonal polymorph) were first observed in experiments involving explosions1. Several classes of meteorites2,3 contain microcrystalline diamond aggregates that are thought to be produced by impacts with the Earth or in space. Diamonds have also been found in association with several Russian impact craters4 and in Cretaceous/Tertiary boundary impact ejecta5,6; these too have most often been interpreted as having formed by shock in the solid state4. Here we report the occurrence of diamond lonsdaleite plates and cubic diamond in association with silicon carbide, in impact melts from the Ries crater in southern Germany. We interpret these occurrences as evidence that these phases can be formed by chemical vapour deposition from the ejecta plume of an impact crater. It follows that cubic diamond and silicon carbide may be formed at any impact site from vaporized carbon-bearing rocks, and hence may be used as a reliable diagnostic tool for hypervelocity impact on Earth. This process may also explain the occurrence of diamonds found in sediments (carbonados7), which may result from the 'heavy bom-bardment' period of early Earth history, rather than from mantle-derived diatremes8.
Arden John W.
Gilkess W. R. K.
Gilmour Iain
Hough Robert M.
Milledge Judith H.
No associations
LandOfFree
Diamond and silicon carbide in impact melt rock from the Ries impact crater 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 Diamond and silicon carbide in impact melt rock from the Ries impact crater, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Diamond and silicon carbide in impact melt rock from the Ries impact crater will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1182010