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

• 来源期刊: 科学通报(英文版)
• 学科: 地球科学
• 年，卷（期）: 2011,（15）
• 页码范围: 1579-1587
• 页数: 9页
• 分类号: P588.125
• 语种: 中文

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.