关键词: 花岗岩, 构造环境, 恰其海, 新疆

Abstract: The Qiaqihai area is located in Jimunai County of Altay district and Hefeng County of Tacheng district, western Junggar of Xinjiang. The area is at the northern margin of Kazakstan-Junggar plate. The Qiaqihai intrusion is mainly pinkish red, middle-coarse grained biotite K-feldspar granite and secondly, biotite granite. They are classified as the A₂-type granite based on geochemical discrimination, indicating a tectonic setting at the late period of the major collisional plate or at the extendable period of the post-collisional phase. The SHRIMP U-Pb zircon age for the Qiaqihai alkali-feldspar granite intrusion is (290.7±9.3) Ma (1σ), representing the product of the post-collision magmatic activity during Early Permian. These show that Qiaqihai area has come into an extension setting of the post-collisional stage since then.

Key words: granite, tectonic setting, Qiaqihai area, Xinjiang