摘要
中国岩浆型Ni-Cu-(PGE)硫化物矿床主要出露于中亚造山带(新疆北部的天山-阿尔泰地区)、华北克拉通北缘(吉林-辽宁-北京-河北-内蒙古)和华北克拉通西南缘(甘肃)、扬子克拉通西-北缘(陕西-四川-云南)的广大地区,受控于镁铁质-超镁铁质岩体,具有成群成带分布的特征。这类矿床依其岩石类型和地质特征可划分为3类,即产于镁铁质-超镁铁质侵入体中的基底Ni-Cu-(PGE)硫化物矿床、产于与溢流玄武岩有关侵入体中的Ni-Cu-(PGE)硫化物矿床和产于科马提岩中的Ni-Cu-(PGE)硫化物矿床。这类矿床的成矿时代主要集中于新元古代早期(1000～800 Ma)和古生代晚期(295～250 Ma)两个时间段,所对应的地球动力学背景分别为Rodinia超大陆聚合与裂解阶段、活动造山带后碰撞和二叠纪溢流玄武岩大规模喷发阶段,且均与超级地幔柱活动有关。这类矿床依其成矿构造环境可划分为4类,即古大陆边缘裂谷型、地幔柱型、弧后拉张型以及造山带后碰撞型。这类矿床按其成矿构造环境、成岩成矿时代和地质特征可划分为4个成矿区带,即新元古代与Rodina超大陆聚散有关的Ni-Cu-(PGE)硫化物矿床、华北克拉通北缘Ni-Cu-(PGE)硫化物矿床、中亚造山带后碰撞Ni-Cu- (PGE)硫化物矿床和峨眉地幔柱区Ni-Cu-(PGE)硫化物矿床。
Magmatic Ni-Cu-(PGE) sulfide deposits in China mainly outcrop over vast areas in Central Asian orogenic belt (Tianshan-Altay region in northern Xinjiang), on the northern margin of the North China craton (Jilin-Liaoning-Beijing-Hebei-Inner Mongolia) and its southwestern margin (Gansu) and on the western and northern margins of the Yangtze craton (Shaanxi-Sichuan-Yunnan). They are controlled by mafic-ultramafic intrusions and occur in groups and zones. According to their rock types and geological characteristics, these deposits may be divided into three types: basal Ni-Cu-(PGE) sulfide deposits in mafic-ultramafic intrusions, Ni-Cu-(PGE) sulfide deposits in intrusions related to flood basalts and Ni-Cu-(PGE) sulfide deposits in komatiite. The metallogenic epochs of these deposits are mainly early Neoproterozoic (1000 similar to 800 Ma) and late Paleozoic (295 similar to 250 Ma), and their corresponding geodynamic settings are assembly and breakup of the supercontinent Rodinia, post-collision of active orogenic belts and substantial eruption of Permian blood basalt, which are all associated with activities of mantle superplumes. According to the tectonic settings, these deposits may be divided into four types, i.e. : paleocontinental-margin rift type, mantle plume type, back-arc extensional type and orogenic postcollisional type. According to the tectonic settings, rock- and ore-forming epochs and geological characteristics, they are divided into four metallogenic provinces (belts), i.e. : early Neoproterozoic Ni-Cu-(PGE) deposits associated with convergence and divergence of the supercontinent Rodinia, Ni-Cu-(PGE) deposits on the northern margin of the North China craton, Ni-Cu-(PGE) deposits associated with postcollision of the Central Asian orogenic belt and Ni-Cu-(PGE) deposits in the Emeishan mantle plume region.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第10期2561-2594,共34页
Acta Petrologica Sinica
基金
国家自然科学基金项目(40402012)
地质过程与矿产资源国家重点实验室基金(GPMR200627)
地质大调查项目(1212010634001)联合资助.
