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“八五”期间在辽西１／５万区调过程中，通过野外地质调查、岩石地层学研究、微古植物和同位素测年，以及原岩建造和地球化学研究，将测区一套浅变质岩，从太古宙原建平群中解体出来，建立魏家沟岩群，划归为中元古代。按其原岩组合划分为上、下两个岩组。下岩组为一套碳酸盐岩、碎屑岩和泥质岩建造的浅变质岩，形成于被动陆缘构造环境。上岩组为变质的钙碱性基性－中酸性火山岩，形成于活动大陆边缘。这些岩层在中元古代晚期遭受了强烈的造山运动改造，发生了变质与变形。魏家沟岩群的建立对探讨华北板块北缘古大陆边缘地壳构造演化具有重要意义。
During the period of “the Eighth Five-Year Plan”, in the process of 1/50000 regional adjustment in western Liaoning, through the field geological survey, lithostratigraphy, microfossil and isotope dating, and the original rock construction and geochemical study, a set of shallow metamorphism Rock, from the Archean primitive Jianping group in the disintegration, the establishment of Wei Jiagou rock group, is classified as Mesoproterozoic. According to their original rock combination is divided into upper and lower two rock group. The Lower Rock Formation is a set of shallow metamorphic rocks of carbonate, clastic and argillaceous formed in the passive continental marginal tectonic setting. The Shangshi Formation is a metamorphic calc-alkaline base-acid volcanic rock formed on the active continental margin. These strata suffered a great orogeny transformation in the late Mesoproterozoic period, causing metamorphism and deformation. The establishment of the Weijiagou rock mass is of great significance in exploring the tectonic evolution of the ancient continental margins in the northern margin of the North China Plate.