藏北羌塘盆地晚三叠世地层特征与对比

羌塘盆地上三叠统日干配错组、土门各拉组和肖茶卡组、那底岗日组分别分布于南、北羌塘凹陷。在以往研究和笔者在中国地质调查局青藏重点沉积盆地油气资源潜力分析项目工作基础上,通过对各地层单元的详细研究和区域对比,从古生物、岩石组合、沉积系列、地层单元的接触关系、年代地层进行了综合分析。结果显示北羌塘凹陷那底岗日组与南羌塘凹陷日干配错组和土门各拉组的时代主要为晚三叠世诺利期—瑞替期,三者为羌塘晚三叠世诺利期—瑞替期裂陷盆地形成过程中的同期异相的火山-沉积系列。北羌塘凹陷肖茶卡组的是残留陆表海沉积产物,其时代主要为晚三叠世卡尼期-诺利期早期,与那底岗日组、日干配错组和土门各拉组均为上下对比关系。

Correlation of Upper Triassic strata in Qiangtang Basin, northern Tibet

There exist Upper Triassic Riganpeicuo Formation,Tumengela Formation,Xiaochaka Formation and Nadigangri Formation in Qiangtang basin,with the first two formations distributed in the southern part whereas the last two distributed in the northern part of Qiangtang depression.Based on a detailed comparative study of the oil-gas resource potential in major sedimentary basins of the Qinghai-Tibet Plateau,the authors analyzed the paleontology,lithologic assemblage,sedimentary sequence,contact relationship and chr...