Abstract

• Hermyingyi-Taungphila area is located in the central granite range of the Dawei Sn-W region. In the study area, the greisen-bordered quartz veins are hosted by a Paleocene granite and Mergui Group. The granite samples have high A/CNK [molecular proportion of Al2O3/ (CaO+ Na2O+K2O)] values, ranging from 1.47 to 4.34, which is greater than 1.1 and reveals the S-type. The granite is highly siliceous (SiO2 = 75-80 wt.%), peraluminous, calc-alkaline, and strongly fractionated. It possesses the enrichment of Cs, Rb, Th, U, K, and La and the depletion of Ba, Sr, and Eu, indicating magma is mainly derived from the lower continental crust. The tetrad REE patterns with strong negative Eu anomalies (Eu/Eu*- 0.01-0.04) and (La/Sm)N (0.6-0.9) are consistent with the characteristics of a highly fractionated or evolved magmatic-hydrothermal system. Combined with previous geochronological data, the present geochemical data provides that the granites were formed at a collisional setting.