北美最大规模铜-金-钼矿床——珀博矿床发现及其启示  

The discovery of the Pebble giant porphyry Cu-Au-Mo deposit in Southwest Alska,USA, and its enlightenment significance

作　　者：聂凤军[1] 蒋喆[1,2] 李强峰[1,2] 王丰翔[1,2] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]石家庄经济学院,河北石家庄050031

出　　处：《地质通报》2015年第6期999-1010,共12页Geological Bulletin of China

基　　金：中国地质调查局项目(编号:12120115065901;12120115068701;1212011120326)

摘　　要：对北美地区规模最大的珀博铜-金-钼矿床的发现历史、产出环境、地质特征和形成作用进行了论述,对如何将该矿床的成矿模式和技术方法运用于中国的找矿实践进行了讨论。研究结果表明,大兴安岭和吉黑成矿省侏罗纪—白垩纪火山-沉积岩地层分布广泛,各类深大断裂纵横交错,燕山期中酸性侵入岩十分发育,物化探异常显著,是寻找大型斑岩型铜多金属矿床的有利地段。采用指示性矿物法、水文和土壤地球化学法,结合系统的中大比列尺地质填图是在兴蒙造山带东北段寻找隐伏铜多金属矿床的有效途径。The Pebble deposit is located 320 km southwest of Anchorage, Alaska, USA. It is one of the newly discovered supergiant porphyry copper-gold-molybdenum deposits. A total resource of 10.78 billion tons（Bt） has been defined, making it the fourth largest porphyry copper deposit and the first porphyry gold deposit in the world. The Pebble deposit consists of two ore zones： East and west ore zones which are approximately equal in size. The east and west zones have been regarded as two coeval hydrothermal centers within a single system. Previous studies indicate that the Pebble deposit was formed from the mixing of magmatic fluids with meteoric water. The deposit is, therefore, believed to be a product of Mesozoic multiphase tectonic-magmatic event caused by coeval subduction of the Pacific oceanic plate under the northern American continent. The easternmost section of the Sino-Mongolian border region is located at the intersection of several crustal-scale structures. The Jurassic-Cretaceous intrusive and extrusive rocks are widely distributed and hosted a number of molybdenum, gold and copper-polymetallic prospective areas and anomalous zones. This setting is similar to fertile porphyry environments in southwestern Alaska of USA and suggests that the easternmost section of the Sino-Mongolian border region is highly favorable for porphyry copper-polymetallic deposit exploration.

关 键 词：斑岩型铜-金-钼矿床 地质特征 成矿作用 找矿勘查 阿拉斯加 珀博 中蒙边境东段 

分 类 号：P618.2[天文地球—矿床学]