作　　者： ; ; ; ; ;

机构地区： 贵州大学资源与环境工程学院

出　　处： 《地质与勘探》 2015年第2期238-245,共8页

摘　　要： 震旦系灯影组是新发现的一个重要成磷层位,该层位磷矿床在国内较为少见。震旦纪灯影期是新发现的一个成磷时期,其含磷岩系具有独特的矿床地质特征。以贵州瓮安灯影组磷矿为例,从矿床地质特征、沉积环境、磷矿石特征及矿石组构等方面进行研究,结果表明:矿石为叠层石磷块岩,以胶状结构为主,少量碎屑状结构及放射状和波状层纹结构,构造为柱状及层纹状;矿石矿物主要为白云质胶磷矿,含少量重结晶微晶质磷灰石;化学成分主要为P2O5、Ca O、Mg O,总量在73.56%~87.9%,平均81.74%;矿床形成于陆棚浅海碳酸盐台地水下隆起边缘半局限盆地内的生物藻丘,隆起边缘的潮下局限环境是矿床形成的主要环境,矿床的形成与生物直接相关,为生物及生物化学成矿。 The Sinian Dengying Formation is a newly discovered vital phosphorus stratum,of which the phosphorite deposit is rare in China. As a new stage of phosphorus mineralization,the geological characteristics of its phosphate rock series is unique. Taking the phosphrite deposit of Weng'an Dengying Formation in Weng'an county,Guizhou province as an example,this paper presents the geological characteristics,sedimentary environment,characteristics of phosphorite and ore structures of this type of deposits. The results indicate that the ore is stromatolitic phosphorite,with natural colloidal structure,bearing a small amount of clastic structure,or radial structure and laminated wavy structure. The cylindrical and lamellar structures are predominant. Dolomitic phosphoorite,which contains a small amount of recrystallization microcrystalline apatites,is the main mineral. The primary chemical compositions are P2O5,CaO and MgO,with total content of 73. 56% ~ 87. 9%,and the average value 81. 74%. The phosphorite deposit was formed in a algae hilly- land in a semi- confined basin in subaqueous uplift edges of a continental shelf,shallow water carbonate platform. The confined basin environment of the edges of subaqueous uplift of the subtidal zone in the carbonate platform is the main metallogenic setting for this phosphorite deposit. At the same time,phosphorite deposit's formation was directly related to biology of algae,and the genesis of the phosphorite deposit was biological and biochemical mineralization.

关 键 词： 灯影组 叠层石磷块岩 沉积特征 矿床成因

领　　域： [天文地球] [天文地球]