藏北赤布张错地区中-晚侏罗纪砂岩地球化学特征与构造背景探讨

本文通过对藏北赤布张错地区中晚侏罗纪砂岩、粉砂岩样品进行主量元素地球化学分析,利用分析结果判别物源区大地构造背景,探讨北羌塘盆地在该时期的性质及演化。研究结果表明:北羌塘中段的赤布张错地区物源区大地构造背景为以活动大陆边缘为主被动陆缘次之。结合地层学、沉积学和岩石学,赤布张错地区在中-晚侏罗世经历了陆缘海盆地-弧后前陆盆地的演化旋回,体现了金沙江缝合带和班公湖-怒江缝合带生产发展在区内的沉积响应。

Middle-late Jurassic Sandstone in Northern Tibet Red Cloth Zhangcuo Geochemical Characteristics and Tectonic Setting

This article through to northern Tibet middle-late Jurassic sandstone and siltstone in red cloth Zhang Cuo samples geochemical analysis of the main elements using discriminant provenance analysis tectonic background, explore the nature of the north qiangtang basin in the period, and evolution.The results show that the part of red cloth Zhang Cuo region and in the middle of the north qiangtang provenance is given priority to with active continental margin tectonic background passive margin.Combination of stratigraphy, sedimentology, petrology, red cloth Zhang Cuo region has experienced epicontinental sea basin in the middle-late Jurassic-arc first evolutionary cycle of the foreland basin, embodies the jinsha river suture zone and class lake-nujiang suture zone production development in the area of the sedimentary response.