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天津蓟县剖面的中元古界雾迷山组是一套厚达3300m、形成时限近亿年(1310±20Ma,?1207±10Ma)的碳酸盐岩地层。在该套地层中,具近似对称相序组构的环潮坪型碳酸盐米级旋回层序特别发育。其近似对称的相序组构,以及普遍的1:4叠加形态,表明它们与短偏心率旋回具有成因关联,被形象地命名为雾迷山旋回层,用来代表真正的碳酸盐沉积旋回。总的来讲,构成叠层石生物层及凝块石生物丘的厚层块状灰质白云岩及白云质灰岩组成旋回层之中部,其上和下则为潮坪相白云岩及砂泥质白云岩,旋回层之顶为具古土壤层帽的泻湖相白云质泥页岩,最终形成一个类似于生物礁相序的近对称
The Mesoproterozoic Wumishan Formation in Jixian section of Tianjin is a set of carbonate rock formations with a thickness of 3300m and a formation time of nearly 100 million years (1310 ± 20Ma and 1207 ± 10Ma). In this set of strata, the Huanpeng type carbonate sequence with the approximate symmetrical phase sequence is especially developed. Its approximately symmetrical phase sequence structure, as well as the general 1: 4 superposition morphology, suggests that they are genetically related to the short eccentricity cycle and are vividly named the Misty Mountain Cyclone, representing the true carbonate depositional cycle . In general, the thick layers of massive dolomitic dolomites and dolomitic limestones that make up the monolayer of stratum biomasses and clinker bio-mounds make up the central part of the gyration, with tidal flat dolomites and sand mud above and below Dolomite, the top of the gyration layer is a lagoon dolomitic mud shale with an ancient soil cap, and finally a near symmetry similar to the reef phase sequence