层序地层研究在豫北小南海石膏找矿的应用与效果

Application and effect of sequence stratigraphy in gypsum prospecting in Xiaonanhai area,north Henan Province

华北奥陶纪多次出现潮上蒸发环境,可以形成多层含膏沉积。笔者在豫北小南海地区测制了大比例尺地层剖面,通过层序地层研究及沉积环境分析,建立了层位控矿的膏盐找矿模式,确定马家沟组一、三、四段角砾状泥灰质白云岩是石膏矿的赋存层位,二、五段厚层灰岩为溶剂灰岩和水泥灰岩的赋存层位。通过钻探控制,提交了石膏、水泥灰岩双大型矿床。

There were many supratidal evaporation environments in the ordovician period in north China,which could form multi-layer gypsum-bearing deposits.Based on the study of sequence stratigraphy and the analysis of sedimentary environment,the authors have established the gypsum-salt prospecting model controlled by strata,the brecciated Marl Dolomite of the first,third and fourth members of Majiagou formation is the hosting horizon of gypsum deposit,and the thick limestone of the second and fifth members is the hosting horizon of solvent limestone and cement limestone.Through drilling control,the double large-scale deposit of Gypsum and cement limestone has been submitted.