辽西建昌盆地义县组上部英安岩的^(40)Ar/^(39)Ar年龄及其地质意义  

^(40)Ar/^(39)Ar STEPWISE HEATING AGE AND ITS GEOLOGICAL IMPLICATION OF THE DACITE AT THE UPPER PART OF THE YIXIAN FORMATION IN JIANCHANG BASIN,WESTERN LIAONING

作　　者：郑月娟[1] 李永飞[1] 郜晓勇[1] 苏飞[1] 

机构地区：[1]沈阳地质矿产研究所,辽宁沈阳110034

出　　处：《地质与资源》2011年第3期167-171,共5页Geology and Resources

基　　金：中国地质调查局"古亚洲洋构造体制与滨太平洋构造体制叠加转变综合调查与研究";"松辽盆地及其外围地层-构造格架与油气资源前景调查"(编号1212010813070)资助

摘　　要：建昌盆地义县组可分为两部分:下部以巨厚的沉积层为主,自下而上称为要路沟层、罗家沟层,局部地区沉积层之下有中基性火山岩;上部(罗家沟层之上)为酸性、中酸性火山岩系夹沉积层.罗家沟层与义县-北票地区尖山沟(砖城子)层可进行生物地层学对比.对义县组上部的一件英安岩样品进行40Ar/39Ar年代学研究,获得年龄为120 Ma,应与义县地区义县组顶部火山岩(金刚山层之上)对比.建昌地区义县组顶、底均可与义县地区大致对比.The Yixian Formation in the Jianchang basin,Liaoning Province consists of a series of volcanic-sedimentary rocks,which can be divided into two members from bottom to top.The first member is composed mostly of sedimentary rocks,including Yaolugou bed（the lower） and Luojiagou bed（the upper）,with intermediate-basic volcanic rocks at the bottom of the member.The second member is mainly acid and intermediate volcanic rocks with clastic rocks.Biostratigraphically,the Luojiagou bed may be correlated to the Jianshangou（Zhuanchengzi） bed of Yixian Formation in Yixian-Beipiao area.The 40Ar/39Ar stepwise heating dating of the dacite sample at the upper part of the Yixian Formation in Jianchang basin yields an age of 120 Ma,which agrees with previous results obtained by K-Ar,Ar-Ar and U-Pb methods for the top of volcanic rocks of the Yixian Formation in the Yixian area.

关 键 词：建昌盆地 义县组上部 英安岩 40Ar/39Ar同位素测年 辽西 

分 类 号：P597[天文地球—地球化学]