冀北大西沟金矿床主要侵入岩体年代学及构造、成矿意义  

Geochronology of Main Intrusive Rocks in Daxigou Gold Deposit,Northern Hebei Province and Their Tectonic-Metallogenic Singnificane

作　　者：蒋喆[1,2] 江思宏[2] 刘翼飞[2] 刘云杰 薄进兴 陈建志 张洪鹏 

机构地区：[1]中煤地质工程总公司,北京100040 [2]中国地质科学院矿产资源研究所,北京100037 [3]丰宁金龙黄金工业有限公司,河北丰宁068350

出　　处：《地质学报》2016年第8期1817-1834,共18页Acta Geologica Sinica

基　　金：中国地质大调查项目(编号121201103000150006)资助

摘　　要：大西沟金矿床位于华北克拉通北缘中东段，是冀北地区近年来发现的一处重要金矿床。矿区范围内主要侵入岩体的U-Pb同位素测年分析结果显示，似斑状花岗闪长岩的结晶年龄为（1858±12）Ma，中细粒花岗岩为（1829±14）Ma，蚀变辉长岩脉为（1807±18）Ma，花岗斑岩为（135～136）Ma，流纹斑岩为（133.8±1.0）Ma，主要集中于古元古代（1807～1858Ma）与早白垩世（133-136Ma）2个时期，分别是古元古代与中生代燕山期构造-岩浆活动的产物。矿区南部花岗斑岩可能为大西沟金矿成矿提供了重要的热源和成矿流体，成矿时代推测为早白垩世。该时期华北克拉通北缘及邻区处于岩石圈减薄作用阶段，伸展体制的张裂构造作用诱发的富碱性岩浆作用及相关流体活动为该区金、钼矿床的形成提供了重要的动力和物质来源，是该区多金属成矿作用的主要控矿因素。Located in the middle section of the northern margin of the North China Craton and the Inner Mongolia axis, Daxigou gold deposit is a newly descoveried deposit in the north section of the Hebei province.The U-Pb isotopic dating analysis of the main intrusive rocks in Daxigou gold deposit shows that, the porphyritic granite has the zircon crystallization age of （1858±12）Ma , the medium-fine grained granite is（1829±14）Ma, alteration gabbro vein is （1807±18）Ma, the potassic granite and rhyolite zircon crystallization age are respectively （135～136）Ma and（133.8±1.0）Ma . Their diagenesis mainly occurred in Paleoproterozoic （1807～1858Ma） and Early Cretaceous（133-136Ma）,are the product of the Paleoproterozoic and Yanshanian tectonic magmatic activities. The potassic granite may provided heat source and the fluid for the the ore-forming process, so we infer that the it was occurred in the early Cretaceous.This epoch is an important period of crustal stretching and thinning environment of northern margin of North China Craton. The alkali rich magmatism and related fluid activities induced by tension structures provided important power and material for the formation of gold and molybdenum deposits.

关 键 词：成岩时代 侵入岩 大西沟 冀北地区 华北克拉通北缘 

分 类 号：P618.51[天文地球—矿床学]