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

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.