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中国西部新特提斯洋由班公湖—怒江小洋盆和雅鲁藏布江主洋盆及其间的拉萨小陆块组成。雅鲁藏布江主洋盆演化可分为4个阶段:(1)裂谷起始阶段(P2);(2)扩张阶段(T1—J2-3),拉萨陆块向北漂移,班公湖—怒江洋(J2-3—K1)自东而西封闭,拉萨地块拼合到亚洲陆块上;(3)俯冲阶段(K1—E2),雅鲁藏布江主洋盆急剧向北俯冲,形成冈底斯陆缘火山弧和日喀则弧前复理石堆积。喜马拉雅地区由被动边缘沉积(K2-3)向局部残留的台型浅海沉积过渡(E1—E22);(4)碰撞阶段(E32—Q),从始新世晚期起,印度陆块与亚洲大陆碰撞。对应于新特提斯洋的演化,中国西部中新生代发生3期构造变格,分别形成陆缘和陆内2大序列盆地。(1)构造变格第1期(T3—K1):被动陆缘(唐古拉)及台内坳陷(昌都—思茅)形成(T3—J2);位于陆内的塔里木、准噶尔两侧产生陆内前陆盆地;(2)构造变格第2期(K2—E):由于印度板块的碰撞,而持续发育陆内盆地;(3)构造变格第3期(E3—N):由于印度大陆的楔入,青藏高原强烈隆升,西部山前形成山前坳陷。
The Neo-Tethys Ocean in western China consists of the Bangong Lake-Nujiang basin and the main Yarlung Zangbo basin and the Lhasa small land massif between them. The evolution of the main ocean basin of the Brahmaputra can be divided into four stages: (1) the initial stage of the rifting (P2); (2) the expansion stage (T1-J2-3) (J2-3-K1) is closed from the east to the west, and the Lhasa massif is spelled into the Asian continent. (3) In the subduction phase (K1-E2), the main oceanic basin of the Brahmaputra subducted northward to form the Gangdese Margin volcano Arc and Shigatse arc pre-accumulation of complex stones. The Himalayan region was transitioned from passive edge deposition (K2-3) to locally residual platform-type shallow sea sediments (E1-E22); (4) During the collision phase (E32-Q), from the Late Eocene, collision. Corresponding to the evolution of the Neo-Tethys Ocean, the Mesozoic and Cenozoic in western China occurred in three stages of structural transformation, forming two major sequences of continental margin and intracontinental basin. (T3-K1): Passive margins (Tangula) and Taichung Depression (Qamdo-Simao) are formed (T3-J2). Tarim and Junggar have intracontinental Foreland Basin; (2) Structural Evolution Phase 2 (K2-E): Continuously developing intracontinental basins due to the collision of the Indian Plate; (3) E3-N: , The Qinghai-Tibet Plateau strongly uplifted and the piedmont depression formed in the western piedmont.