中文摘要：

内蒙古查干敖包石英闪长岩位于西伯利亚板块南缘白音乌拉一东乌珠穆沁旗碱性花岗岩带东部，在时空分布上与查干敖包矽卡岩型铁一锌矿床关系密切。石英闪长岩中的岩浆结晶锆石SHRIMP U—Pb测年结果显示^206Pb／^238U加权平均年龄为237±6Ma（1a），MSWD=0．63。根据野外地质调查和室内研究资料，并结合上述同位素年龄数据可以推测查干敖包石英闪长岩和铁-锌矿床形成于印支期，它们同属兴蒙造山带碰撞后拉张构造环境的产物。

英文摘要：

Located in the eastern part of the Baiyinwula-Dong Ujimqin Banner alkali granite belt on the southern edge of the Siberian plate, the Qagan Obo quartz diorite stock has an intimate temporal and spatial relationship with the Qagan Obo Fe-Zn deposit. SHRIMP magmatic zircon U-Pb dating of quartz diorite stock yields an age of 237 ± 6 Ma （1σ）, with the MSWD value being 0.63. Based on field geological investigation and laboratory data in combination with the result of zircon dating, it is suggested that the quartz diorite and its associated FeZn ore bodies were formed in Indosinian period. Both of them were formed in a post-collision extensional tectonic setting within the Xing＇ anling-Mongolia orogenic belt.