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在西藏改则昂拉仁错地区测制了多条拉嘎组剖面,详细描述了改则县拉清乡蹦克弄拉剖面。讨论了拉嘎组的岩性组合特征及横向变化规律。首次在拉嘎组内建立了2个腕足类生物组合带,即Choristitesxainzaensis-Eomarginifera组合带和Neospiriferkubeiensis-Fusispiriferplicatus-Stepanoviella(Bandoproductus)组合带,前者的时代为晚石炭世早期,后者为早二叠世,大致与萨克马尔—阿丁斯克(Sakmarian-Artinskian)期相当。拉嘎组为冰海陆棚沉积,根据冰碛物特征细分为坠石冰碛砾岩、块状冰碛砾岩和冰海水下扇砾岩3种类型,并认为拉嘎组从早到晚总体由冰海内陆棚→冰海外陆棚→冰海内陆棚构成一个完整的沉积旋回。
A number of sections of the Laga Formation have been tested in the area of Ngala Ram in Tibet. The characteristics of lithology assemblage and its lateral variation are discussed. For the first time, two brachiopod assemblages were established in the Raga group, namely the Choristitesxainzaensis-Eomarginifera assemblage and the Neospiriferkubeiensis-Fusispiriferplicatus-Stepanoviella (Bandoproductus) assemblage. The former is dated to the Early Carboniferous and the latter to the Early Permian , Roughly equivalent to the Sakmarian-Artinskian period. The Lhaga Formation is a shelf of ice and sea sediments and is subdivided into pendant conglomerate, massive moraine conglomerate and ice-sea sub-fan conglomerate according to characteristics of the glacial moraines. It is considered that the Luga Formation from early to late The overall ice-shelf inland → ice-shelf in the ice → ice inland shelf to form a complete sedimentary cycle.