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南天山野云沟石炭系上部碎屑岩中存在典型的鲍玛序列浊积构造以及滑塌构造、包卷层理等重力流沉积构造。由地层剖面分析和岩相特征及粒度统计分析的C-M图解可知,南天山野云沟石炭系上部的碎屑岩形成于海底扇环境,可划分出杂乱砾岩相(A_1)、无碟状构造块状砂岩相(B_2)、近基浊积岩相(C)、远基浊积岩相(D)、滑塌角砾岩相(F)、页岩夹硅质岩相(G)等岩相类型,它们组合构成了Walker海底扇模式中的扇根、扇中、扇端。因而,首次证实南天山野云沟石炭系中存在深水海底扇沉积。古流向资料计算结果表明,其物源来自南侧的古塔里木陆块,古坡向倾向北。碎屑物常量化学成分投点表明,其形成时构造背景属被动大陆边缘。
In the Upper Carboniferous upper clastic rocks in the Nanyunting area, there are typical turbidite structures of the Bowman sequence and gravitational-stream sedimentary structures such as slump structure and bedding layering. Based on the CM maps of stratigraphic and lithofacies characteristics and statistical analysis of grain size, it can be seen that the upper clastic rocks in the Upper Carboniferous of the Youyunou Formation in the southern Tianshan Mountains are formed in the submarine fan environment and can be divided into a conglomerate-conglomerate facies (A_1) (B 2), turbidite facies (C), turbidite facies (D), slip breccia facies (F) and shale clastic siliceous facies The types, which make up the fanhead, fan-in, and fan-end in Walker sea fan mode. Thus, for the first time, it is confirmed that there is deep-water seafloor fan deposition in the Carboniferous of the Youyun Gully in the South Tianshan Mountains. The results of paleocurrent flow show that the provenance comes from the ancient Tarim block in the south, and the ancient slope tends to the north. Constituents of the detritus constant chemical composition indicate that the tectonic setting of the detritus is a passive continental margin.