新疆东准噶尔萨尔托海石英二长闪长岩岩体形成时代及构造环境

The formation epoch and tectonic environment of quartz monzonite diorite in Sartokay, east Junggar, Xinjiang

摘要: 新疆东准噶尔萨尔托海石英二长闪长岩体属于晚古生代额尔齐斯构造-岩浆带。通过对萨尔托海石英二长闪长岩体的岩相学，主量、微量和稀土元素岩石地球化学特征及LA-ICP-MS锆石U-Pb年龄研究，认为萨尔托海石英二长闪长岩属于偏铝质、高钾钙碱质的镁质花岗岩类；富集大离子亲石元素（LILE，如Rb、Ba），亏损高场强元素（HFSE，如Ta、Nb、Hf和Ti），轻稀土元素富集，轻、重稀土元素分馏程度较高，负Eu异常不明显，表明形成于早二叠世（277.4±5.1Ma）后碰撞阶段的板内构造环境中。

Abstract: Quartz monzonite diorite in Sartokay of east Junggar belongs to the Paleozoic Ertix tectonic-magmatic belt. Rock geochemistry shows that quartz monzonite diorite in Sartokay belongs to magnesian grantoid of metaluminous, high-K calc-alkaline series, with enrichment of LILE, depletion of HFSE, and concentration of LREE. LREE and HREE fractionating degree is relatively high, and the negative anomaly of Eu is not obvious. The age of 277.4±5.1Ma indicates Early Permian after the collision in an intraplate tectonic environment.