内蒙古扎鲁特旗地区中侏罗统塔木兰沟组的厘定  

REVISION OF THE JURASSIC TAMULANGOU FROMATION IN THE JARUD QI AREA, INNER MONGOLIA

作　　者：丁秋红[1] 李晓海[1] 姚玉来[1] 王杰[1] 宗文明[1] 郜晓勇[1] 李文博[1] 

机构地区：[1]中国地质调查局沈阳地质调查中心(沈阳地质矿产研究所),辽宁沈阳110034

出　　处：《地质与资源》2015年第5期402-407,共6页Geology and Resources

基　　金：中国地质调查局项目"内蒙古1:25万扎鲁特旗幅(L51C004001)区调修测"(编号1212011120670);"松辽盆地外围三维地质调查"(编号1212011220242)

摘　　要：扎鲁特旗地区发育的一套中性火山岩,前人曾将其置于二叠纪"大石寨组"、"青凤山组",缺少古生物资料和测年数据.本次1∶25万区域地质调查,在原1∶20万划分的"大石寨组"、"青凤山组"的安山岩中采集了同位素测年样品,采用全岩激光40Ar/39Ar法测年,对火山岩样品进行了年代学研究,结果表明火山岩年龄为(172.7±2.0)^(165.2±1.3)Ma.鉴于这套火山岩地层岩石组合特征清楚,时代依据充分,在区域上具有一定的延展性和可填图性,故将这套火山岩地层重新厘定为中侏罗统塔木兰沟组.A suite of intermediate volcanic rocks in the Jarud Qi area of Inner Mongolia was defined as the PermianDashizhai Formation and Qingfengshan Formation by previous researchers, but they were lack of paleontological and datingdata. In the recent 1：250 000 regional geological survey, the isotopic dating samples are collected from the andesites ofDashizhai and Qingfengshan Formations defined in the former 1：200 000 geological survey. The chronology of volcanic rocksamples is studied based on the laser 40Ar/39Ar dating method. The result shows that the age is （ 172.7±2.0）-（165.2±1.3） Ma.In consideration of the clear characteristics of stratigraphic rock assemblages, sufficient time basis and certain extensibilityand mapping possibility, this suite of volcanic strata is redefined as the Middle Jurassic Tamulangou Formation.

关 键 词：地层厘定 同位素年龄 塔木兰沟组 扎鲁特旗 内蒙古 

分 类 号：P534[天文地球—古生物学与地层学]