Petrography,mineral chemistry and shock metamorphism of Yamato 984028 lherzolitic shergottite  

作　　者：HU Sen FENG Lu LIN YangTing 

机构地区：[1]Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China [2]Graduate University of Chinese Academy of Sciences, Beijing 100049, China

出　　处：《Chinese Science Bulletin》2011年第15期1579-1587,共9页

基　　金：supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-YW-110 and KZCX2-YW-Q08)

摘　　要：Y984028 is a new lherzolitic shergottite,consisting of poikilitic and non-poikilitic lithologies.The mafic silicates are FeO-poor,and the chromite is TiO 2-poor in the poikilitic lithology compared to the grains in the non-poikilitic lithology.This meteorite shares similarmineral petrography andmineral chemistry with GRV 99027,but is not paired with the latter because of their different shock-induced features.Y984028 was severely shocked and experienced no significant thermal metamorphism after the main impact event.Hence,Y984028 serves as a probe for the study of meteorite impact processes on terrestrial surfaces.The melt veins in Y984028 are characterized by the absence of any high-pressure polymorphs,the presence of abundant smallmineral fragments,and the prevailing granulation textures of olivine and chromite.These features are consistent with adiabatic melting during the release of shock-induced high-pressure and quenching at ambient pressure.Y984028 is a new lherzolitic shergottite, consisting of poikilitic and non-poikilitic lithologies. The mafic silicates are FeO-poor, and the chromite is TiO2-poor in the poikilitic lithology compared to the grains in the non-poikilitic lithology. This meteorite shares similar mineral petrography and mineral chemistry with GRV 99027, but is not paired with the latter because of their different shock-induced features. Y984028 was severely shocked and experienced no significant thermal metamorphism after the main impact event. Hence, Y984028 serves as a probe for the study of meteorite impact processes on terrestrial surfaces. The melt veins in Y984028 are characterized by the absence of any high-pressure polymorphs, the presence of abundant small mineral fragments, and the prevailing granulation textures of olivine and chromite. These features are consistent with adiabatic melting during the release of shock-induced high-pressure and quenching at ambient pressure.

关 键 词：矿物岩石学 矿物化学 变质作用 二氧化钛 激波诱导 撞击过程 陆地表面 压力淬火 

分 类 号：P588.125[天文地球—岩石学]