CAJ | 학술논문

The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2-6 km wide,with an area of 140 km2,located at the north margin of the Bashikaogong Basin in the north Altun terrain.It intruded into schist,metapelite and metatuff of Precambrian ages.This granitoid complex consists of darkish quartz diorite,grey granite,pink granite and pegmatite.Geochemically,the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies,and the other granites have S-type affinity and to high-K calc-alkaline series.Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites,which is 481.6±5.6 Ma for quartz diorite,437.0±3.0 Ma-433.1±3.4 Ma for grey granite and 443±11 Ma-434.6±1.6 Ma for pink granite,respectively.Combined with regional geology,we think that the quartz diorite formed in tectonic environment related to oceanic crust subduction and the granites in post-collision.