Electron petrography of shock-deformed olivine in stony meteorites
Electron petrography of shock-deformed olivine in stony meteorites
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石陨石中冲击变形橄榄石的电子岩相分析
DOI：
10.1016/0012-821x(75)90158-2
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发表时间：
1975
影响因子：
5.3
通讯作者：
D. J. Barber
中科院分区：
文献类型：
--
作者：
J. R. Ashworth;D. J. Barber
我们已经研究了橄榄石的高压电子显微镜在陨石显示冲击效应，即普通陨石Olivenza和Hedjaz，reuilite Goalpara和碳质球粒陨石阿连德。实验变形和退火橄榄石的观察结果进行了比较，Olivenza和Hedjaz遭受低温冲击，这产生了高密度的[001]螺旋位错和裂纹。阵列的裂缝被发现对应于平面的功能，可以看到光学和负责马赛克。Goalpara遭受了非常强烈的冲击，其最终结果是橄榄石的广泛再结晶，新的晶粒具有独特的低密度位错分布。阿连德作为一个整体并没有受到冲击，但个别部分有变形和加热的历史，可以追溯到陨石聚集之前。
We have studied olivine by high-voltage electron microscopy in meteorites showing shock effects, namely the ordinary chondrites Olivenza and Hedjaz, the ureilite Goalpara and the carbonaceous chondrite Allende. The observations are compared with published data on experimentally deformed and annealed olivine.Olivenza and Hedjaz have suffered low-temperature shock, which has produced high densities of [001] screw dislocations and cracks. Arrays of cracks are found to correspond to planar features which can be seen optically and to be responsible for mosaicism. Goalpara has suffered very heavy shock, of which the final result is extensive recrystallization of the olivine, and the new grains have distinctive low-density distributions of dislocations. Allende has not been shocked as a whole, but individual parts have deformational and heating histories dating from before the aggregation of the meteorite.