塔西地区中—新生代盆-山-原镶嵌构造区:砂砾岩型铜铅锌-天青石-铀-煤成矿系统

Mosaic Tectonics of Mesozoic to Cenozoic Basin-mountain-plateau in the Western Tarim Basin,China:Glutenite-type Cu-Pb-Zn-celesite-U-coal Metallogenic System

塔里木盆地西部地区(简称"塔西地区")中—新生代盆-山-原镶嵌构造区形成了铜铅锌-天青石-铀-石膏-煤-天然气等多矿种同盆共存富集成藏成矿,是中国陆内特色成矿单元。以成矿系统理论和波浪镶嵌构造理论为指导,采用构造岩相学研究方法,对砂砾岩型铜铅锌-天青石-铀-煤成矿系统的物质-时间-空间结构模型进行研究,探索该陆内特色成矿单元内区域成矿规律。按照塔西地区盆-山-原耦合转换不同期次的构造岩相学序列、构造岩相学组合类型、原型盆地和盆地动力学等综合角度,将塔西地区砂砾岩型铜铅锌-天青石-铀-煤成矿系统划分为燕山期铜多金属-铀-煤成矿亚系统、燕山晚期—喜山早期铅锌-天青石-铀成矿亚系统、喜山晚期铜-铀成矿亚系统。它们在物质-时间-空间分布规律上受塔西地区盆-山-原镶嵌构造区挤压-伸展转换过程控制显著。燕山期铜多金属-铀-煤成矿亚系统形成于中生代陆内走滑拉分断陷盆地中,受对冲式厚皮型逆冲推覆构造系统、裙边式复式向斜构造和碱性辉长辉绿岩脉群侵入构造系统等复合控制,形成于盆地正反转构造期并耦合了深部热正反转构造作用。燕山晚期—喜山早期铅锌-天青石-铀成矿亚系统分布在乌拉根晚白垩世—古近纪挤压-伸展转换盆地中,受后展式厚皮型前陆冲断褶皱带、斜歪复式向斜构造和层间滑脱构造带复合控制,砂砾岩型铅锌-铀矿床形成于盆地正反转构造高峰期,而天青石矿床形成于盆地负反转构造期初期。喜山晚期铜-铀成矿亚系统形成于新生代周缘山间咸化湖盆,受前展式薄皮型前陆冲断褶皱带等复合控制。

Multiple deposits of Cu-Pb-Zn-celesite-U-gypsum-coal-gas are enriched in mosaic tectonics of Mesozoic to Cenozoic basin-mountain-plateau, the western Tarim Basin, which is the special intracontinental mineralization element in China. Guided by metallogenic system theory and theory of wave-mosaic tectonics, based on the method of tectonic lithofacies, the matter-time-space patterns for glutenite-type Cu-Pb-Zn-celesite-U-coal metallogenic system were studied in order to better understand regional metallogenic regularities for this special intracontinental mineralization element. According to the sequences and combinations of tectonic lithofacies, prototype basin and basin dynamics, the glutenite-type Cu-Pb-Zn-celesite-U-coal metallogenic system in the western Tarim Basin may be classified into Yanshanian metallogenic sub-system of Cu-polymetallic-U-coal, Late Yanshanian-Early Himalayan metallogenic sub-system of Pb-Zn-celesite-U, and Late Himalayan metallogenic sub-system of Cu-U. Their matter-time-space distributions might be obviously controlled by the compression-extension converting basin in the mosaic tectonics of basin-mountain-plateau, the western Tarim Basin. Yanshanian metallogenic sub-system of Cu-polymetallic-U-coal is located in Cenozoic intracontinent apart-pulled basin, and is synthetically controlled by hedge-type base-involved fold-and-thrust slice, ruched multiple syncline and intrusive tectonic system of gabbro-diabase dykes. They are formed during the stage of basin-positive-inversion, and coupled by positive inversion by thermal materials derived from the upper mantle. Whereas, Late Yanshanian-Early Himalayan metallogenic sub-system of Pb-Zn-celesite-U is located in Cretaceous to Palaeogene compression-extension converting basin, and is synthetically controlled by rear-propagation base-involved fold-and-thrust slice at the southern edge of the southwestern Tianshan, Wulagen inclined synclina and interlayer slip structure. The glutenite-type Pb-Zn-U deposits form during the peak stage of basin-positive-inversion; however, the celesite deposit forms during the beginning stage of basin-negative-inversion. Nevertheless, Late Himalayan metallogenic sub-system of Cu-U is located at Mesozoic intermountain enclosed salted-lake-basin, and is controlled by fold-and-thrust slice belt with piggyback propagation and thin-skin type.