江苏泰州寺巷口陨石中熔长(冲击)玻璃的研究

Maskelynite in Sixiangkou Chondrite from Taizhou, Jiangsu

用扫描电镜、透射电镜和电子探针对江苏泰州寺巷口陨石的详细研究发现,该陨石中有两种产状的熔长玻璃出现。第一种分布在橄榄石、古铜辉石、陨硫铁和铁纹石等矿物之间。第二种呈液滴状或长条状分布于辉石和橄榄石球粒的裂隙中。球粒外的斜长石已经变成了熔长玻璃,球粒中的部分斜长石保持结晶状态。根据熔长玻璃的特征以及橄榄石等的炉条状结构估算,寺巷口陨石受到的冲击压力约在35～50GPa之间,相当于Dodd等划分的冲击相e。

The maskelynite in Sixiangkou chondrite from Taizhou, Jiangsu has been studied with SEM、TEM、and EPMA. It has been found that there are two occurences of the maskelynite. One is the interstitial grains between olivine, diopside, bronzite, kamacite and troilite. They are amorphous. The other occurs within the barred olivine and bunched bronzite chondrules. They remain partially as crystalline phase. Based on the maskelynite features and the barred structure of olivine it is proposed that the shock pressure experienced by the Sixiangkou chondrite is in the range 35～50GPa and is corresponding to the strongly shocked stage in the Stoffler's classification or the e-shock phase in the Dodd's classification.