惠民凹陷沙河街组一段白云岩特征及其成因分析

Genesis of the dolostones from the first member of the Shahejie Formation in the Huimin depression,Shandong

惠民凹陷沙河街组一段发育大量的湖相碳酸盐岩,综合岩心、录井、地化及微观资料分析碳酸盐岩特征。碳酸盐岩中发育大量的白云岩,其常见岩石类型包括生物碎屑云岩、灰质藻云岩、砾屑云岩、鲕粒云岩、泥(粉)晶云岩五大类;且白云岩在深湖、半深湖、浅湖、滩坝环境均有发育,垂向上与油页岩、泥岩、生物灰岩及火山岩共生。研究表明,沙一段白云岩为次生交代的产物,且海侵作用、古气候条件和火山活动均为湖相白云岩的形成创造了条件。

There widely occur in the Huimin depression the dolostones including bioclastic dolostone, lime algal dolostone, dolorudite, oolitic dolostone and micritic dolostone developed in the abyssal lake, bathyal lake, shallow lake, and shoal and bar environments. Vertically, these dolostones are associated with oil shale, mudstone, bioclastic limestone and volcanic rocks, and interpreted as the secondary replacement products. The transgression, palaeoclimate and volcanism have exerted an important effect on the formation of the lacustrine dolostones.