用热释光和稀有气体方法研究我国若干普通球粒陨石的热历史

A study on thermal history of some Chinese ordinary chondrites by TL and noble gases method

测定了我国１１个Ｈ型、６个Ｌ型和３个ＬＬ型球粒陨石的热释光特征。Ｈ型球粒陨石的ＴＬ峰温和峰宽分别为１６３－２０６℃平均和８３－１３７℃平均，Ｌ型和ＬＬ型球粒陨石分别为１８３－２０３℃平均和１１１－１４３℃平均。依据ＴＬ数据和已发表的稀有气体同位素数据，引入了（３Ｈｅ暴露年龄／２１Ｎｅ暴露年龄）－诱发ＴＬ灵敏度－（４Ｈｅ气体保存年龄／４０Ａｒ气体保存年龄）图，这种图形是鉴别不同陨石热历史的一种有效方法。

Induced thermoluminescence(TL)properties of Chinese 11H,6L and 3LL chondrites have been measured.TL peak temperature and peak width are 163-206℃,Av.and 83-137℃ for H chondrites,183-203℃,and 111-143℃,for L and LL,respectively. Recently fallen Chinese ordinary chondrites have TL peak width generally smaller than those of ordrinary chondrites from other regions.Based on our TL sensitivity data and published noble gases data, a 3He exposure age/21Ne exposure age-Induced TL sensitivity-4He gas retention/40Ar gas retention diagram is introduced. This type of diagram is a powerful tool for distinguishing different thermal histories of meteorites.