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金沙江结合带是一条古特提斯弧后洋盆消亡的俯冲消减杂岩带。弧后洋盆形成于早石炭世-早二叠世。晚泥盆世晚期已具有雏型,早二叠世是洋盆扩张的鼎盛时期,早二叠世晚期向西俯冲,在金沙江结合带中形成3条消减杂岩带,金沙江弧一盆系于志留纪末在早古生代变质“软基底”的基础上开始生成、发展和演化,经历了泥盆纪弧后裂谷盆地阶段(D)、早石炭世一早二叠世的弧后洋盆阶段(C_1-P_1)、早二叠世晚期-晚二叠世的洋壳俯冲消减阶段(P_1~2-P_2)、早三叠世晚期-中二叠世的弧-陆碰撞阶段(T_1-T_2)、中三叠世晚期-晚三叠世早期的火山裂谷盆地阶段(T_2~2-T_3~1)、晚三叠世中期-白垩纪的前陆盆地阶段(T_3~2-K)和老第三纪-第四纪的陆内汇聚阶段(E-Q)。
The Jinshajiang belt is a subducted and depleted complex belt with the disappearance of the ancient Tethyan arc oceanic basin. The arc-ocean basin formed in the Early Carboniferous-Early Permian. Early Late Devonian has a prototype, the Early Permian is the heyday of the ocean basin expansion, subduction westward in the Early Permian, formed in the Jinshajiang belt with three abating complexes, Jinsha River arc basin Based on the Early Paleozoic metamorphic “soft basement” at the end of Silurian, began to develop, develop and evolve. It experienced the Devonian post-arc rift basin stage (D), the Early Carboniferous-Early Permian arc back ocean During the Early Permian-Late Permian oceanic crust subduction (P 1 -2-P 2), during the Early Triassic-Middle Permian arc-continental collision (T 1 -T2), the Middle Triassic-Early Triassic volcanic rift basin stage (T_2 ~ 2-T_3 ~ 1), the middle Triassic-Cretaceous foreland basin stage (T_3 ~ 2-K ) And the Tertiary-Quaternary Intracontinental Convergence (EQ).