摘要
通过对康滇古陆东侧彝良洪沟和西侧盐源小高山晚二叠世沉积充填序列和沉积环境分析,认为古陆两侧沉积时限和富有机质页岩空间展布存在差异。古陆西侧小高山地区黑泥哨组自下至上沉积环境为滨岸-火山溢流-沼泽-三角洲,下部玄武岩显示峨眉山玄武岩第四次喷发溢流特征,向西至泸沽湖地区出现三套玄武岩夹层,说明西部沉积时间早,向东超覆于康滇古陆。富有机质页岩分布在黑泥哨组下部沼泽环境中,累计厚度大,具有较好的资源潜力。古陆东侧昭通彝良洪沟宣威组自下至上沉积环境为河流-三角洲-沼泽,无玄武岩夹层表明该地区沉积时限晚于西部小高山地区。富有机质页岩分布在宣威组上部沼泽环境中,累计厚度薄,资源潜力有限。
Based on the analysis of the Late Permian sedimentary filling sequence and sedimentary environment in the Yilianghonggou on the east side of the Kangtien old land and the Yanyuanxiaogaoshan on the west side,it is believed that there are differences in the depositional time period and the spatial distribution of organic-rich shales on both sides of the old land.The sedimentary environment of the Heinishao Formation in the Xiaogaoshan area on the west side of the old land is coast-volcanic overflow-swamp-delta upwards.The basalt in the lower part shows the characteristics of the fourth eruption and overflow of the Emeishan basalt.Three sets of basalt interbeds appear in the Lugu Lake area to the west.It indicates that the deposition time in the west was earlier,and it overlaps on the Kangtien old land to the east.The organic-rich shale is formed in a swamp environment in the lower part of the Heinishao Formation,with a large accumulated thickness and a good resource potential.The sedimentary environment of the Xuanwei Formation on the east side of the old land is river-delta-swamp upwards.The absence of basalt interlayers implies that the depositional time of this area is later than that of the western small alpine area.The organic-rich shale is accumulated in a swamp environment in the upper part of the Xuanwei Formation,with a thin cumulative thickness and limited resource potential.
作者
门玉澎
闫剑飞
余谦
张茜
张海全
康建威
曹竣锋
Men Yupeng;Yan Jianfei;Yu Qian;Zhan Qian;Zhang Haiquan;Kang Jianwei;Cao Junfeng(Chengdu Center,China Geological Survey,Chengdu,Sichuan 610081;Key Laboratory of Sedimentary Basin and Oil and Gas Resources,Ministry of Natural Resources,Chengdu,Sichuan 610081)
出处
《中国煤炭地质》
2022年第9期1-3,42,共4页
Coal Geology of China
基金
国家科技重大专项(2016ZX05034-004)。
关键词
康滇古陆
晚二叠世
沉积环境
富有机质页岩
Kangtien old land
Late Permian
sedimentary environment
organic-rich shale
