晚三叠世乡城弧间盆地的形成演化与成矿
The evolution and mineralization in the Xiangcheng inter-arc basin,western Sichuan during the Late Triassic
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摘要: 乡城弧间盆地在晚三叠世时受甘孜.理塘洋由拉张到汇聚和金沙江洋由汇聚到碰撞的影响,先后堆积了由拉张沉降到汇聚抬升的火山岩系列组合,同时伴随着来自再旋回造山带物源区的复理石沉积。在上三叠统图姆沟组上部的中酸性火山岩中发现具呷村式大型矿床的成矿地质背景,是寻找呷村式大型矿床的重点靶区。Abstract: The Xiangcheng inter-arc basin in western Sichuan is a NNW-directed elongated basin intermediate between the Jinshajiang suture and Garze-Litang suture. A suite of volcanic associations with the flysch sediments derived from recycled orogens was successively accumulated in the basin during the Late Triassic due to the extension and convergence of the Garze-Litang Ocean and the convergence and collision of the Jinshajiang Ocean. The geological back-ground of mineralization in the intermediately acidic volcanic rocks from the Upper Triassic Tumugou Formation in the basin is found to be similar to that of the Gacun-type ore deposits. It is clear that these intermediately acidic volcanic rocks in the Xiangcheng inter-arc basin in western Sichuan is expected to be an improtant target area for the prospecting and exploration of the Gacun-type ore deposits.