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雅鲁藏布江缝合带中段硅质岩中发现三个放射虫动物群组合,其地质时代分别为中、晚三叠世,晚侏罗世-早白垩世和早白垩世。硅质岩为生物成因。中、晚三叠世硅质岩和晚侏罗世-早白垩世硅质岩SiO_2平均含量分别为90．24％和92．58％,Al/(Al+Fe+Mn)平均值分别为0．75和0．74,MnO/TiO_2平均值分别为0．36和1．24,Ce/Ce*平均值分别为1．15和1．03,La_N/Ce_N平均值均为0．85和0．93,为生物成因大陆边缘型硅质岩。早白垩世硅质岩SiO_2含量为94．12％,Al/(AI+Fe+Mn)比值0．59,MnO/TiO_2比值4．30,Ce/Ce*为0．60,La_N/Ce_N平均值1．59,为生物成因远洋型硅质岩。中、晚三叠世放射虫硅质岩、浊积岩组合及硅质岩地球化学特征,表明雅鲁藏布江地区中、晚三叠世存在强烈裂陷海盆构造环境；晚侏罗世-早白垩世放射虫硅质岩和层状玄武岩组合代表藏南特提斯初始洋盆环境；早白垩世放射虫硅质岩及共生的枕状玄武岩代表藏南特提斯成熟洋盆。
Three radiolarian animal assemblages were found in the mid-section of the Brahmaputra suture zone in the Yarlung Zangbo River. The geological epochs are Middle-Late Triassic, Late Jurassic-Early Cretaceous and Early Cretaceous, respectively. Silicalites are biological causes. The average SiO 2 content of mid-to-late Triassic siliceous rocks and Late Jurassic-Early Cretaceous silicalites is 90.24% and 92.58% respectively, and the average values of Al / (Al + Fe + Mn) are 0 .75 and 0.74 respectively, the average values of MnO / TiO_2 were 0.36 and 1.24, the average values of Ce / Ce * were 1.15 and 1.03 respectively, and the average values of La_N / Ce_N were 0.85 and 0.74 .93, a biogenic origin of marginal-type silicic rocks. The Early Cretaceous SiO 2 content is 94.12%, the ratio of Al / (AI + Fe + Mn) is 0.59, the ratio of MnO to TiO_2 is 4.30, the Ce / Ce * is 0.60, the average La_N / Ce_N 1.59, for the genesis of oceanic type chert. Middle and late Triassic radiolarian chert, turbidite assemblages and cherts geochemical characteristics, indicating that there is a strong rift basin tectonic environment in the middle and late Triassic in the Yarlung Zangbo River region; Late Jurassic-Early Cretaceous radiation The combination of chert and stratiform basalts represents the initial oceanic environment of the Tibetan Tethys. The Early Cretaceous radiolarian chert and the symbiotic pillow-shaped basalts represent the mature oceanic basin of the South Tethys.