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在川滇金沙江-哀牢山结合带以东,从未发现过海相侏罗纪地层。笔者最近在其以东数百公里的四川省木里县瓦厂地区的甘孜-理塘结合带以东发现广泛分布的含层孔虫Claodocoropsismirabilis,珊瑚Thecosmiliacf.WeberiRegny,Pratethmoscf.discus,水螅Spongiomorphacf.robusta等生物群的海相侏罗纪地层。此套地层下部为陆源碎屑岩,上部为富产层孔虫、珊瑚、水螅的正常广海台地相碳酸盐岩,底部以底砾岩与下伏晚三叠世曲嘎寺组平行不整合接触。其岩性、生物组合均可与西藏昌都地块侏罗纪地层对比。本区侏罗纪沉积盆地是在晚三叠世古特提斯洋闭合的基础上,随新特提斯洋开合而发展演化的,消亡于古近纪初期。
In the Sichuan-Yunnan Jinsha River - Ailao Mountain east of the belt, never found marine Jurassic strata. Recently, the authors found that the widely distributed foraminifer Claodocoropsismirabilis, Thecosmiliacf.WeberiRegny, Pratethmoscf.discus, Spongiomorphacf.robusta, were found to the east of the Garzê-Litang belt in the Wuli area of Muli County, Muli County, Sichuan Province, Other marine biota Jurassic strata. The lower part of this set of strata is terrigenous clastic rocks. The upper part is the normal Guanghai platform facies carbonates of the upper Pleurotus ostreatus, corals and hydra. The bottom is basal conglomerate and the underlying Triassic Quqasi Formation is not parallel Integrated contact. Its lithology and biological assemblage can be compared with the Jurassic strata of the Qamdo block in Tibet. The Jurassic sedimentary basin in this area was developed and evolved on the basis of the closing of the Late Triassic Paleo-Tethys Ocean and the evolution of the Neo-Tethys Ocean. It died in the early Paleogene.