| 摘要: |
| 江达-维西陆缘火山弧为金沙江弧后洋盆向西俯冲消减和斜向碰撞过程中形成,其过程经历了俯冲造弧-碰撞成弧-张裂成盆的复杂发展历史。早二叠世晚期—晚二叠世(P12-P2)形成俯冲型弧火山岩,早中三叠世(T1+2)形成碰撞型弧火山岩,晚三叠世早期(T31)于裂谷盆地中发育“双峰式”火山岩。晚三叠世早期(T31)裂谷盆地从北向南形成生达-车所-鲁麻弧后盆地、徐中-鲁春-红坡上叠(弧后)裂谷盆地和箐口塘-催依比-上兰上叠(弧后)裂谷盆地三个次级半深海-深海盆地。生达-车所-鲁麻弧后盆地的拉裂时间为11.6 Ma,速度为0.27cm/a,距离为63km;徐中-鲁春-红坡上叠(弧后)裂谷盆地的拉裂时间为16.1 Ma,速度为0.43cm/a,距离为140km;箐口塘-催依比-上兰上叠(弧后)裂谷盆地的拉裂时间16.1 Ma,速度为0.36cm/a,距离为116km。弧火山岩中形成有沉积-改造型铜、金、银、铅、锌多金属矿,裂谷(火山)盆地中形成有喷流-沉积型铜、金、银、铅、锌多金属矿。晚三叠世早期火山-沉积盆地已成为三江地区中生代重要的成矿盆地。 |
| 关键词: 江达-维西 陆缘火山弧 形成演化 成矿作用 |
| DOI： |
| 附件 |
| 投稿时间：1999-04-07 |
| 基金项目: |
|
| The evolution and mineralization of the Jomda-Weixi continental marginal volcanic arc, southwestern China |
| WANG Li-quan, PAN Gui-tang, LI Ding-mou, XU Tong-rui |
| (Chengdu Institute of Geology and Mineral Resources, Chengdu 610082, Sichuan, China) |
| Abstract: |
| The Jomda-Weixi continental marginal arc in southwestern China originated from the westward subduction,consumption and oblique collision of the Jinshajiang back-arc oceanic basin,and shows a long and complex history,spanning several phases of arc-building by subduction,arc formation by collision and basin formation by rifting.The subduction-type arc volcanic rocks appeared during the late Early Permian to Late Permian;the collision-type arc volcanic rocks were formed during the Early and Middle Triassic,and the “bimodal” volcanic rocks occurred in the rift basins during the early Late Triassic.The rift basins in this period are assigned to the bathyal-abyssal basins,including,from north to south,the Sinda-Chesuo-Luma back-arc basin,Xuzhong-Luchun-Hongpo (back-arc) rift basin,and Qingkoutang-Cuiyibi-Shanglan superimposed (back-arc) rift basin.The rifting may be traced back to:11.6 Ma at a rate of 0.27 cm/a and a distance of 63 km for the Sinda-Chesuo-Luma back-arc basin; 16.1 Ma at a rate of 0.43 cm/a and a distance of 140 km for the Xuzhong-Luchun-Hongpo superimposed (back-arc) rift basin,and 16.1 Ma at a rate of 0.36 cm/a and a distance of 116 km for the Qingkoutang-Cuiyibi-Shanglan superimposed (back-arc) rift basin.The “sedimentary-reworking type” copper,gold,silver,lead and zinc polymetallic deposits are found to be hosted in the arc volcanic rocks,whereas the “(volcanic) exhalation-sedimentary type”copper,gold,silver,lead and zinc polymetallic deposits occur in the rift basins.These volcanic-sedimentary basins are considered as important Mesozoic metallogenic basins in the Nujiang-Lancangjiang-Jinshajiang area,southwestern China. |
| Key words: Jomda-Weixi continental marginal volcanic arc formation and evolution mineralization |
