秦皇岛石门寨地区奥陶系亮甲山组豹皮灰岩与马家沟组白云岩成因研究

发布时间：2018-05-23 08:19

本文选题：秦皇岛 + 奥陶系　；参考：《西北大学》2015年硕士论文

【摘要】：秦皇岛石门寨地区广泛发育奥陶系的海相碳酸盐岩,论文选取亮甲山剖面下奥陶统亮甲山组和中奥陶统马家沟组为研究对象,结合野外实测剖面资料与室内微观分析,运用镜下鉴定、X-衍射、扫描电镜、电子探针测试、包裹体研究、阴极发光分析技术,系统地研究了亮甲山组豹皮灰岩与马家沟组白云岩的岩石学、沉积微相及成岩作用特征,并分别对其白云化机理进行了讨论。主要结果如下：1.亮甲山组主要岩石类型为含生物碎屑灰岩、竹叶状砾屑灰岩、泥晶灰岩、粉晶白云岩、亮晶生物碎屑—球粒灰岩、豹皮灰岩；马家沟组岩石类型为含白云石微晶灰岩、粉-细晶白云岩、麦粒状白云岩、泥晶白云岩。2.亮甲山组识别出6种沉积微相,由底到顶依次为RMF18：内缓坡局限海相含介形虫生屑颗粒灰岩；RMF11：中缓坡相磨圆砾屑(内碎屑)灰岩;RMF9-A.中缓坡相磨圆内碎屑漂砾灰岩；RMF9-B:中缓坡相内碎屑-生屑粒泥/漂砾灰岩；RMF22：内缓坡潮缘带相纹层状白云岩/泥晶灰岩；RMF26：内缓坡浅滩相生物碎屑粒泥灰岩；RMF28-A：内缓坡浅滩相生物碎屑颗粒灰岩/粒泥灰岩,伴随大量扰动构造(豹皮灰岩)；RMF28-B:内缓坡浅滩相亮晶生物碎屑一球粒灰岩。3.马家沟组识别出2种主要的沉积微相,分别为RMF19-A:内缓坡相潮缘带含白云石微晶灰岩,RMF19-B:内缓坡相潮间-潮上带泥晶白云岩。4.亮甲山组各类岩石多经历早期成岩作用的改造,而马家沟组岩石遭受了多期埋藏成岩作用的改造。5.亮甲山组的豹皮灰岩为生物潜穴内充填物在混合水作用下发生白云化而形成,其中具环带结构的白云石为后期成岩流体改造的产物。6.马家沟组白云岩由底到顶白云石有序度呈降低趋势,白云化作用逐渐减弱,由埋藏白云化模式转变为准同生白云化模式。粉-细晶白云岩是在早期白云岩化的基础上,在埋藏期由多期白云化作用而形成；麦粒状白云岩也经历了埋藏成岩期的改造,受晶体自身生长习性及成岩流体的影响,使白云石具单向延伸且延伸方向垂直于结晶轴c的特点。
[Abstract]:The main results are as follows : 1 . The main rock types of the bright A - shan Formation are bioclastic limestone , bamboo leaf - like grater limestone , micrite limestone , fine - crystal dolomite , bright - crystal biological debris - pellet limestone and leopard - skin limestone .
The rock types of Majigou Formation are dolomite - containing microcrystalline limestone , fine - grained dolomite , grain - like dolomite and micrite dolomite .
RMF11 : Medium - gentle slope facies - rounded gravel ( internal debris ) limestone ; RMF9 - A . Medium - gentle slope facies rounded inner debris boulder limestone ;
RMF9 - B : Middle gentle slope facies internal debris - debris grain mud / boulder limestone ;
RMF22 : The inner gentle slope tidal zone is bedded with bedded dolomite / micrite ;
RMF26 : Inner gentle slope shoal facies bioclastic debris marl ;
RMF28 - A : Inner gentle slope shallow shoal facies biodebris granule limestone / grain limestone , with large disturbance structure ( leopard skin limestone ) ;
In this paper , two main sedimentary facies are identified in RMF28 - B : inner gentle slope shoal facies bright crystal biological debris . 3 . Majigou Formation identifies two main sedimentary facies , respectively RMF19 - A : inner gentle slope facies tidal zone contains dolomite microcrystalline limestone , RMF19 - B : inner gentle slope facies tidal zone - tidal zone micrite dolomite .
The grain - like dolostone also experiences the transformation of the burial diagenesis stage , which is influenced by the growth habit of the crystal itself and the diagenesis fluid , so that the dolomite has one - way extension and the extending direction is perpendicular to the characteristic of the crystal axis c .
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P588.245

【相似文献】