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中朝地台北缘之内蒙古中段北纬42°以南地区,存在南、北两条近于平行的中元古代裂谷系,长约700km,宽60—80km。古裂谷中分别沉积了年龄为1464—1546Ma 的白云鄂博群和渣尔泰群后地台阶段碎屑岩、白云质碳酸盐岩、火山-沉积岩,并伴生有铁、磷、稀土、萤石及层控型铅锌铜矿。在北纬42°以北地区,主要为古生代活动陆缘的褶皱山带,断续发育有标志古板块运动相关的蛇绿岩套及高压变质相带等,它们大致沿北东东方向延伸,赋存有铬、镍钴、金、铜、钼、铅锌、钨、锡、铁等矿床。近年研究表明,中元古代—古生代奠定了本区板块构造格局,大面积断陷和火山岩与中—新生代库拉-太平洋板块向西消减有关。
North of the northern margin of Inner Mongolia in the northern margin of China-DPRK terraces, there are two parallel Paleoproterozoic rift systems in the south and north, about 700 km long and 60-80 km wide. Paleogene, dolomitic carbonate rocks and volcanic-sedimentary rocks are formed in the Paleo-rift, with the age of 1464-1546Ma, respectively. They are accompanied by iron, phosphorus, rare earth, fluorite And layer-controlled lead-zinc-copper mine. In the area north of latitude 42 ° north, it is mainly a fold belt of the Paleozoic active continental margin. There are intermittent ophiolite sets and high-pressure metamorphic belts related to the signs of the ancient plate movement. These belts extend roughly east and east of the NE direction There are chromium, nickel and cobalt, gold, copper, molybdenum, lead and zinc, tungsten, tin, iron and other deposits. Recent studies show that the Mesoproterozoic-Paleozoic emplaces the tectonic framework of this area, and the large-area fault depression and the volcanic rocks are related to the westward depletion of the mid-Cenozoic Kula-Pacific plate.