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青藏高原东缘古近纪盆地的填图和沉积学研究表明,在青藏高原东缘区域性走滑-挤压构造背景下形成的古近纪盆地内广泛发育厚层—巨厚层状的紫红色粗碎屑岩系。其沉积特征指示为一种近源快速堆积的泥石流和辫状河道沉积体,形成于干旱炎热气候条件下的典型陆内冲积扇环境。盆地充填序列、粗碎屑岩层序、动植物化石和盆地内岩浆岩~(40)Ar-~(39)Ar年代学等综合研究结果表明,古近纪盆地内粗碎屑岩大约形成于38～29 Ma。该时期与青藏高原东缘北段(横断山地区)古近纪盆地的形成和南段(兰坪—思茅地区)大盆地的裂解时间基本一致,这很可能预示着青藏高原在晚始新世—早渐新世期间曾发生过整体的快速构造隆升。
The mapping and sedimentology of the Paleogene basin in the eastern margin of the Qinghai-Xizang Plateau show that the Paleogene basin developed in the context of the regional strike-slip-extrusion structure on the eastern margin of the Qinghai-Xizang Plateau is characterized by thick and thick layer of purple Red coarse clastic rock series. Its sedimentary characteristics indicate a rapidly accumulating near-source debris flow and braided channel sediments, forming typical alluvial fan environments in arid and hot climates. The comprehensive study of filling sequence, coarse clastic sequence, animal and plant fossils and magmatic rocks in the basin ~ (40) Ar- ~ (39) Ar chronology shows that the coarse clastic rocks in the Paleogene basin formed about 38 ~ 29 Ma. The formation of the Paleogene basin in the northern segment of the eastern Qinghai-Tibetan Plateau (Hengduanshan area) and that of the large basin in the southern segment (Lanping-Simao area) basically coincided with each other, which probably predicted that the Qinghai- - The whole rapid tectonic uplift occurred during the Early Oligocene.