Chronology and Geochemistry of Acid Intrusions in Chulutaohai Iron Ore,Eastern Kunlun

The Chulutaohai acid intrusions are located in Yemaquan area,eastern Kunlun,between the Kunbei fault and Qimantage magmatic arc intruding into Ordovician clastic rock group of Qimartag Formation and the Late Triassic Elashan Group.The main type of rocks is granite-porphyry and granodio rite-porphyry.Major element,trace element and zircon LA-ICP-MSU-P bdata of Chulutaohai indicate that these intrusions are weakly meta-aluminous to peraluminous calc-alkaline A-type granite,reported in this paper,characterized by significant LILE (Rb,Ba,Th) and LREE and Nb-Ta,depleted with Eu seriously; and for med in post-orogenic extensional tectonic environment,which can be discriminated from variety of tectonic setting associated with trace elements and major elements.The Chulutaohai intrusions were dated at (256.0±9.6) Ma and determined the emplacementage in the Late Permian.