古地理学报2016，Vol.18Issue(4)：581-594,14.DOI:10.7605/gdlxb.2016.04.043
黔中开阳地区震旦纪陡山沱期富磷矿沉积特征与成矿模式
Sedimentary characteristics and mineralization model of high-grade phosphorite in the Sinian Doushantuo Age of Kaiyang area,central Guizhou Province
摘要
Abstract
There were thick and high-grade phosphorite beds in Kaiyang area of central Guizhou Province during the global phosphogenesis events in the Sinian Doushantuo Age.This paper used thin sec-tions observation,stratigraphic comparison and subdivision and sedimentary facies analysis to study the sedimentary characteristics and mineralization model of phosphorite deposits in the Sinian Doushantuo Age in Kaiyang area,central Guizhou Province.The result showed that:(1 ) Kaiyang area was located in north margin of Central Guizhou Old Land which was a phosphorus beach during the Sinian Doushantuo Age.The high-grade phosphorite ore in Kaiyang area was mainly composed of sand clastic phosphate rocks which were formed in the process of sedimentation-diagenesis of phosphorus-rich deposits,during which they were erosion and broken,exposed and leached,accumulated and cemented repeatedly.(2) The palaeogeographic environment and unstable seawater condition controlled the deposition and enrichment of phosphorite in Kaiyang area.Shore face zone like Yangshui or Yongwen which were in a depositional condi-tion with moderately-deep seawater in the Sinian Doushantuo Age was the advantageous metallogenetic zone.Foreshore zone with too shallow seawater and offshore zone with too deep seawater were unbeneficial for phosphorus aggregation and mineralization.(3) The dynamic mineralization model of phosphorite de-posits in Kaiyang area showed that frequent transgression and regression during the Doushantuo Age made phosphate rocks which originally deposited in shore face zone experienced multi-stages erosion,exposure, leaching,cementing and redeposition.Physical winnowing action,weathering and leaching gathered phos-phorus and ultimately led to the formation of high-grade phosphorite.关键词
黔中/震旦纪/陡山沱期/磷矿/成矿模式Key words
central Guizhou Province/Sinian/Doushantuo Age/phosphorite/mineralization model分类
天文与地球科学引用本文复制引用
张亚冠,吴文明,杜远生,陈国勇,刘建中,王泽鹏,徐圆圆,谭代卫,李磊,王大福..黔中开阳地区震旦纪陡山沱期富磷矿沉积特征与成矿模式[J].古地理学报,2016,18(4):581-594,14.基金项目
中国地质调查局地质调查项目（编号12120114016501）和贵州省地质矿产开发局项目（编号黔地矿办发［2013］56号）联合资助。［Co-funded by the Geological Survey Project of China Geological Survey （No．12120114016501） and Project of Bureau of Geology and Mineral Ex-ploration and Development of Guizhou Province （No．［2013］56）］ （）
