塔里木盆地库车河烧变岩的形成年龄  

FORMATION AGES OF BURNED METAMORPHIC ROCKS FROM THE KUQA RIVER SECTION TARIM BASIN

作　　者：业渝光[1] 邬象隆 刁少波[1] 蒋炳南[2] 郑显华[2] 董砚如 

机构地区：[1]地质矿产部海洋沉积开放研究实验室 [2]中国新星石油公司西北石油地质局

出　　处：《海洋地质与第四纪地质》1998年第4期115-119,共5页Marine Geology & Quaternary Geology

基　　金：地质行业科学技术发展基金

摘　　要：用Ｋ－Ａｒ测年技术确定了塔里木盆地库车河剖面上二叠统二次侵入岩的形成年龄为２２７．６±３．３４Ｍａ，还使用ＥＳＲ技术测试了侵入岩和烧变岩中石英氧空位的相对浓度。根据库车河二次侵入岩的Ｋ－Ａｒ年龄，石英氧空位的相对浓度和剂量率，估算出上三叠统塔里齐克组烧变岩的形成年龄为３．２６±０．３Ｍａ，中侏罗统克孜努尔组烧变岩的形成年龄为２．３３±０．２Ｍａ。此外，还讨论了烧变岩形成年龄的可靠性问题。Kuqa River section is the area where the most complete north Tarim Mesozoic,Cenozoic strata outcrop.There are red colored burned metamorphic rocks caused by spontaneous combustion of coal layers in upper Triassic and middle Jurassic formations by the Kuqa River. Formation age of the second intrusive rock in upper Permian formation of Kuqa River section is 227.6±3.34Ma by K Ar dating and the relative concentration of oxygen vacancies in quartz from the second intrusive rock was estimated using the ESR signal intensity of E’ centres (an electron at an oxygen vacancy)after γ ray irradiation and subsequent heating at 300℃(Toyoda et al,1992).The relative concentration of oxygen vacancies in quartz of burned metamorphic rocks was estimated using the same technique.According to K Ar age and the relative concentration of oxygen vacancies in quartz from the second intrusive rocks,we estimated that the formation ages of burned metamophic rocks in upper Triassic and middle Jurassic formations are 3.26±0.3 Ma and 2.33±0.2 Ma respectively.The reliability of the ages is also discussed.

关 键 词：烧变岩 石英 形成年龄 塔里木盆地 

分 类 号：P588.3[天文地球—岩石学] P578.941[天文地球—地质学]