湘西磷块岩的沉积相及沉积模式

基金项目:

地矿部重点科研项目“中国南方震旦纪岩相古地理及成矿作用”的三级课题之一《湘西南晚震旦世陡山沱期岩相古地理及黄铁铅锌矿产远景预测》的部分科研成果

SEDIMENTARY FACIES AND MODEL OF THE PHOSPHORITES IN WESTERN HUNAN

摘要: 湘西怀化-沅陵的陆山沱组磷块岩,是震旦纪场子聚磷区的主要类型之一,分布于扬子地块边缘的江南古岛孤隆起带,沉积于局限台地岛缘潮坪、浅滩和滩后泻湖环境。浅水沉积标志明显。磷质来自华南弧后盆地上升洋流,以化学、生物化学沉淀为主,机械富集较弱。
- 磷块岩 /
- 陡山沱组 /
- 局限台地 /
- 沉积模式
Abstract: Known as the main type of the Sinian phosphorites in the Yangtze phosphorus-accumulating area, the phosphorites in the Doushantuo Formation in the Huaihua-Yuanling region of western Hunan are wide-spread over the uplifted zone of the Jiangnan ancient island arc on the southeastern margin of the Yangtze block, and deposited in the shallow-water environments including tidal flats on the margins of restricted platform islands, beaches and backbeach lagoons. The phosphorus material is derived from the upwelling currents in the Huanan backarc basin. The deposition consists mainly of chemical and biochemical precipitation, with weak mechanical concentration.
- phosphorite /
- Doushantuo Formation /
- restricted platform /
- sedimentary model