摘要
上三叠统巴贡组分布于长江源各拉丹冬地区南北两侧 ,南部靠近羌塘盆地中央隆起带 ,沉积环境为三角洲至浅海相 ,陆源物资供应丰富 ,以砂岩沉积为主 ,地层厚度大。北部雀莫错一带沉积环境为陆棚相 ,陆源物资供应相对较少 ,以泥质岩、灰岩沉积为主 ,生物丰富 ,沉积古地理格局显示出南浅北深的特点。在雀莫错一带采集了大量的菊石化石 ,建立 N odotibetitescf.nodosus- Paratibetitescf.wheeleri组合 ,生物组合所反映的地质时代为诺利早—中期 ,与藏南珠穆朗玛峰地区、藏北唐古拉山地区及青海玉树地区同期地层中的菊石生物群可以很好对比。
The Late Triassic Bagong Formation is distributed on the southern and northern side of Geladandong Mountain. On the southern side near to the middle bulge of the Qiangtang basin because of abundant terrigenous supply this formation is a neritic delta and very thick, dominated by sandstones. In Quemocuo of the northern side it is of shelf facies rich in fossils and dominated by mudstones and limestone. So this formation was deposited of shallow water on the southern side and deep water on the northern side. Near Quemocuo of the northern side a large number of ammonoids were collected and one assemblage called Nodotibetites cf. nodosus-Paratibetites cf. wheeler Assemblage has been established in this paper. The assemblage is considered as of early-middle Norian in age and comparable with the ammonoid assemblage of contemporaneous strata from the Qumolangma region, south Tibet,Tagulashan Mountain area, north Tibet and Yushu region, South Qinghai.
出处
《地层学杂志》
CSCD
北大核心
2003年第2期129-133,137,T002,共7页
Journal of Stratigraphy
基金
中国地质调查局国土资源大调查"西藏地区 1/ 2 5万<赤布张错幅>( I46 C0 0 30 0 1)区域地质调查"(项目编号 2 0 0 0 130 0 0 0 912 1)项目成果之一。
