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东秦岭商丹地区的武关岩群是从原刘岭群北部分解出来的新的构造岩石地层单位，已获得其中变质基性火山岩Ｓｍ－Ｎｄ同位素年龄为（１３８２±３０）Ｍａ，原岩建造主体为碎屑沉积岩－碳酸盐岩－基性火山岩组合。变质基性火山岩及碎屑沉积岩的岩石地球化学特征表明，他们分别属于大陆板内拉斑玄武岩和大陆岛弧－活动陆缘型杂砂岩，因而武关岩群主体形成于中元古代晚期秦岭造山带拉张裂谷体制构造环境，于晋宁期（１０００～８００Ｍａ）的俯冲碰撞造山过程中拼贴于商丹构造带南侧。
The Wu Guan Group in Shangdan area of East Qinling is a new tectonic lithostratigraphic unit that was decomposed from the northern part of the original Liuling Group. The Sm-Nd isotopic ages of metamorphic base volcanic rocks are (1382 ± 30) Ma, Sedimentary Rocks - Carbonate - Basic Volcanic Rock Combinations. The petrogeochemical characteristics of metamorphic basement and clastic sedimentary rocks show that they belong to intra-continental intra-continental tholeiitic basalts and continental island arc-active marginal-type interbedded sandstones, respectively. Therefore, the main body of Wuguan Group was formed in the late Qinling orogeny Zhang rift system tectonic environment collapsed in the Jinning period (1000 ~ 800Ma) subduction collision orogenic collage in Shangdan structural belt south side.