北羌塘盆地中部上侏罗统研究新进展

北羌塘盆地腹地自然条件恶劣 ,地层研究难度极大。经在北羌塘盆地腹地东湖、河湾山、长水河及半岛湖等地进行了详细的岩石地层及生物地层研究工作 ,依据岩石特征和生物化石特征 ,将上侏罗统二分 :下部灰岩层为索瓦组 ,含 L acunosella triobatiformis- Pentithyris vulgaris、Radulopecten fibrosus- Gervillella aviculoides组合 ,其时限为牛津期 ;上部灰岩、碎屑岩互层为白龙冰河组 ,具 Radulopecten scarburgensis、R.moondanensis、Cladophylliaqeibulaensis、Stylosmilia chaputi化石 ,其主体时限为基默里奇期—提塘期 ,顶部可能跨入早白垩世。白龙冰河组的确立 ,是北羌塘盆地上侏罗统岩石地层与生物地层研究上一个新进展

New Advances in the Research on the Upper Jurassic in the Middle of the North Qiangtang Basin

It is difficult to study the strata in the middle of the North Qiangtang Basin, because the natural condition is very poor there. The authors have detailedly researched the lithostratigraphy and biostratigraphy of Donghu,Hewanshan,Changshuihe and Bandaohu. Based on lithostratigraphy and fossil characters, the Upper Jurassic can be divided into two parts. The lower one is the Suowa Formation connsisting of limestones containing Lacunosella trilobatiformis Pentithyris vulgaris, Radulopecten fibrosus Gervillella aviculoides assemblages of Oxfordian age. The upper one is the Bailongbinghe Formation consisting of limestones and clastic rocks and containing Radulopecten scarburgensis, R.moondanensis, Cladophyllia qeibulaensis, Stylosmilia chaputi of Kimmerdgian Berriasian age. The establishing of the Upper Jurassic Bailongbinghe Formation is a new advance in the lithostratigraphical and biostratigraphical researches.