摘要
AN id=EnChDivSummary name="EnDivSummary">Located in the basin overburden area between the Qaidam Basin and the Qimantag Mountain,the Tawenchahan deposit is a typical skarn Fe-polymetallic deposit characterized by heavy sand overburden and various mine-ralization elements.The detailed geological features and he ore-forming age of the Tawenchahan deposit were studied in this paper.In order to obtain the ore-forming age,the authors measured the muscovite separated from skarn magnetite ore in the Tawenchahan Fe-polymetallic deposit by the 40Ar-39Ar incremental heating method,and the results yield a 40Ar-39Ar plateau age of(230.7±2.0) Ma and an isochron age of(229.9±3.5) Ma with MSWD being 1.8.It is shown that the Tawenchahan Fe-polymetallic deposit was formed during Indosinian period.These new age data,combined with the available petrogenetic and metallogenic chronological data obtained by SHRIMP zircon U-Pb,zircon LA-ICP-MS U-Pb,molybdenite Re-Os isochron and Ar-Ar methods in Qimantag area of Qinghai Province,indicate that this deposit was formed from the collisional to post-collisional environment,and belonged to the metallogenic series of Fe-Cu-Pb-Zn-Au polymetallic deposits related to Indosinian collision orogeny in eastern Kunlun.
