川东北旺苍地区三叠-侏罗系岩石特征与物源分析  

Lithologic Character and Material Sources of the Triassic-Jurassic System in the Wangchang Region

作　　者：白华青[1] 

机构地区：[1]中国地质大学(北京)能源学院,北京100083

出　　处：《四川地质学报》2011年第2期127-130,共4页Acta Geologica Sichuan

基　　金：国家自然科学基金联合资助重点项目"四川地块北缘晚古生代-中三叠世构造格局演变及其控油"(40739906)

摘　　要：通过对研究区岩石薄片的镜下观察和主要颗粒成分的统计,结合长石岩屑比值变化规律发现三叠—侏罗系砂岩成分成熟度普遍偏低,其中下中侏罗统相对较高。借助Dickinson和Suczek等提出的砂岩碎屑模型将研究区物源分为再循环造山带和混合物源区两种类型。晚三叠世和晚侏罗世的物源区是龙门山隆起,属于再循环造山带型;早中侏罗世的物源区为米仓山—大巴山和龙门山,但以米仓山—大巴山隆起为主,属于混合物源型。Petrographical study indicates that the Triassic-Jurassic sandstone in the Wangchang region is characterized by low maturity.On the basis of Dickinson-Suczek model of sandstone fragment,the provenance of the Triassic-Jurassic sandstone may be divided into such 2 types as recirculation orogenic zone and mixed provenance.The provenance in the Late Triassic and Late Jurassic was the Longmenshan uplift belonging to recirculation orogenic zone and the provenance in the Early and Middle Jurassic was the Michangshan and the Dabashan belonging to mixed provenance.

关 键 词：晚三叠—侏罗系 岩石特征 物源分析 川东北旺苍 

分 类 号：P512.2[天文地球—地质学]