关家沟组地层位于南秦岭造山带,因缺乏化石证据,其地层时代长期悬而未决,该套地层在南秦岭地区地质演化过程中构造含义始终模糊不清.关家沟组砾岩厚度约为2050m,为一套向上变粗、变浅的进积层序,结构和物质组成上表现为不成熟海相浊积砂岩和砾岩.虽然南北两侧为断层所限,但关家沟组变质变形很弱.北侧为泥盆系三河群,南侧为新元古界横丹群,关家沟组中含有大量花岗岩和火山岩碎屑.对采自其中的花岗岩和火山岩砾石进行了单矿物(斜长石和钾长石)40Ar/39Ar热年代学研究.两个测年结果分别给出了花岗岩和火山岩砾石的冷却年龄为219.69±0.49和216.46±0.59Ma,与早中生代秦岭全面碰撞作用时期(240-220)Ma的构造岩浆活动的时代大体一致,暗示关家沟组可能沉积于晚三叠世Norian晚期，约220M.沉积学分析和热年代学研究表明:关家沟组可能是残余洋盆的沉积充填物.区域上,该残余洋盆为晚古生代一早中生代阿尼玛卿洋与勉略洋或中央造山带南侧的一部分. The Guanjiagou Formation is located in the South Qinling orogenic belt and its age has remained unsettled due to lack of evidence of fossils. The tectonic implications of this suite of strata in the geological evolution of the South Qinling Mountains have always been unclear. The thickness of the conglomerate in the Guanjiagou Formation is about 2050m , Which is a series of upwelling sequences that are thicker and shallower and whose immature marine turbid sandstone and conglomerate are structurally and materially composed.While both the north and south sides are fault-restricted, the metamorphic deformation of the Guanjiagou Formation Very weak.The north of the Devonian Sanhe Group, the south of the Neoproterozoic Hengdan Group, Guanjiagou group contains a large number of granite and volcanic rock debris collected from the granite and volcanic rock gravel from a single mineral ( Plagioclase and potash feldspar) 40Ar / 39Ar thermochronology study.The two dating results show that the cooling ages of granite and volcanic gravel are 219.69 ± 0.49 and 216.46 ± 0.59Ma, respectively, which are consistent with those of the early Mesozoic Qinling 240-220 Ma) tectonic magmatism generally coincide, suggesting that the Guanjiagou Formation may be deposited in late Norian Late Triassic, about 220 M. Sedimentological analysis and geochronology studies show that the Guanjiagou Formation may be a residual ocean Potted sediment fill. Domain, a portion of the residue ocean basins orogen south Paleozoic early Mesozoic Animaqing Yang and Yang Mianlue or central.