摘要
黑龙江省岔路口超大型斑岩钼矿床位于大兴安岭北部,是目前我国东北地区最大的钼矿床,矿体赋存于中酸性杂岩体及侏罗系火山-沉积岩内,其中花岗斑岩、石英斑岩、细粒花岗岩与钼矿化关系密切。本文采用LA-ICP-MS锆石U-Pb定年方法,获得了矿区内二长花岗岩、花岗斑岩、石英斑岩、细粒花岗岩、流纹斑岩、闪长玢岩及安山斑岩的结晶年龄分别为162±1.6Ma、149±4.6Ma、148±1.6Ma、148±1.2Ma、137±3.3Ma、133±1.7Ma和132±1.6Ma。岔路口矿区内至少存在3期岩浆活动,其顺序为侏罗纪火山-沉积岩、二长花岗岩→晚侏罗世花岗斑岩、石英斑岩、细粒花岗岩→早白垩世流纹斑岩、闪长玢岩、安山斑岩。岔路口矿床成矿时代为晚侏罗世,是东北亚大陆内部构造-岩浆活化的产物,形成于古太平洋板块俯冲作用引起的挤压向伸展构造体制转折背景,与我国东部大规模钼矿化爆发期相对应。
The superlarge Chalukou porphyry Mo deposit, located in the northern Great Xing＇an Range, is the biggest Mo deposit in NE China. Its ore bodies are mainly hosted in the intermediate-acid complex and Jurassic volcanic sedimentary rocks, of which granite porphyry, quartz porphyry and fine grained granite are closely associated with Mo mineralization. The high precision LA-ICP-MS zircon U-Pb dating method has been applied to measure the ages of the monzogranite, granite porphyry, quartz porphyry, fine grained granite, rhyolite porphyry, diorite porphyry and andesite porphyry in the Chalukou deposit, corresponding the dated ages of 162±1.6 Ma, 149±4.6 Ma, 148±1.6 Ma, 148±1.2 Ma, 137±3.3 Ma, 133±1.7 Ma and 132±1.6 Ma, respectively. There exist at least three magma activities in the Chalukou deposit. The sequences of the magma activities in the Chalukou deposit are from Jurassic volcanic sedimentary rocks and monzogranite, through late Jurassic granite porphyry, quartz porphyry and fine grained granite, to early Cretaceous rhyolite porphyry, diorite porphyry and andesite porphyry. The Chalukou porphyry Mo deposit formed at the late Jurassic, and was the product of the NE Asia intracontinental tectonic-magma activities, with metallogenesis occurring in a transitional tectonic setting from compression to extension caused by subduction of the Paleo-Pacific Oceanic plate, which is consistent with large scale Mo mineralization epoch in the east of China.
出处
《地质学报》
EI
CAS
CSCD
北大核心
2013年第2期208-226,共19页
Acta Geologica Sinica
基金
云南驰宏资源勘查开发有限公司科研项目(编号201107ZKJS-01)
中国地质调查局地质调查项目(编号1212011085260)
国家自然科学基金项目(编号41172081和41202058)共同资助的成果
