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栾川群出露于东秦岭北部。在栾川群分布区域，古华北板块不同时代的地层往南逆冲，构成北秦岭的太华推覆体。栾川群存在于该推覆体内部的特定逆冲岩席之中，沿这一逆冲岩席追索，确定古华北板块南缘的栾川群是连续沉积的，而受后期推覆构造的改造，栾川群在推覆体前缘的分布是断续相连的。根据地层之间的接触关系、岩浆活动、沉积作用的研究，对栾川群的划分提出了新的看法，认为栾川群由三川组、南泥湖组、煤窑沟组及大红口组构成。栾川群形成于震旦纪晚期，由湖坪及潮下斜坡等滨浅海沉积物构成。栾川群的岩浆岩为具双众数特征的岩套，具典型的大陆裂谷岩浆岩特征。并认为中元古代以来，古华北板块南缘处于裂陷拉张环境。早期的裂陷形成了熊耳群、汝阳群、官道口群及竞坪群，晚期裂陷的过程形成了栾川群、陶湾群，其进一步发育导致以二郎坪群为代表的洋壳生成。
Luan Chuan group exposed in the northern part of the East Qinling. In the distribution area of Luanchuan Group, strata of different ages in the ancient Huabei plate thrust southwards, forming the Taihua nappe body in the North Qinling Mountains. Luanchuan group exists in the specific thrust bed in the interior of the nappe body. Following this thrust bed, it was determined that the Luanchuan group in the southern margin of the ancient Huabei plate was deposited continuously. Due to the transformation of the later nappe structure, The distribution of the front of the nappe body is intermittent. According to the contact relationship between strata, the study of magmatism and sedimentation, this paper puts forward a new view on the division of Luanchuan Group. It is concluded that Luanchuan Group consists of Sanchuan Formation, Nannihu Formation, Meiyaogou Formation and Dahongkou Formation. Luanchuan group formed in the late Sinian, by the lake and tidal flats along the coast of shallow sea sediments. The magmatic rocks in Luanchuan Group are boulder sets with double mode features and typical continental rift magmatic rocks. And that since the Middle Kingdom, the southern margin of the ancient North China Plate in a cracked environment. Early rifting formed the Xiong’er Group, Ruyang Group, Guandaokou Group and Jingping Group. The late rifting formed Luanchuan Group and Taowan Group, and its further development led to the formation of the oceanic crust represented by Erlangping Group.