中亚造山带东部岩浆热液矿床时空分布特征及其构造背景  

Spatial & Temporal Distribution and Tectonic Settings of Magmatic-Hydrothermal Ore Deposits in the Eastern Central Asia Orogen Belt

作　　者：吕斌[1] 王涛[1] 童英[1] 张磊[1] 杨奇荻[1] 张建军[1] 

机构地区：[1]中国地质科学院地质研究所,北京100037

出　　处：《吉林大学学报（地球科学版）》2017年第2期305-343,共39页Journal of Jilin University：Earth Science Edition

基　　金：国家重点基础研究发展计划("973"计划)项目(2013CB429803);桂林理工大学博士科研启动基金;中国地质调查局项目(DD20160102)~~

摘　　要：中亚造山带东部是古亚洲洋构造域、鄂霍茨克洋构造域和古太平洋构造域复合叠加区域,矿产资源丰富。本文收集2000—2014年公开发表文献中岩浆热液矿床约1 200个同位素年龄数据,整理出201个较为可靠的年龄数据,通过数字化编图,揭示成矿的时空分布特征及形成背景。结果显示:中亚造山带东部成矿作用始于寒武纪,出现6个重要成矿期:510~473、373~330、320~253、250~210、210~167、155~100 Ma。510~473 Ma(峰值507 Ma),矿床主要分布在大兴安岭—小兴安岭—张广才岭和北山地区,零星发育热液脉型和斑岩型铁铜金钨矿床,与古亚洲洋开始俯冲及微陆块碰撞拼合有关。373~330 Ma(峰值372Ma),矿床主要分布在南蒙古奥尤陶勒盖地区,发育超大型斑岩型铜金矿床,形成于古亚洲洋俯冲环境。320~253 Ma,矿床主要分布在大兴安岭南段,发育少量斑岩型铜矿床和造山型金矿床;其中,298 Ma在大兴安岭南段首次出现以钼为主的斑岩型矿床,指示该区板块俯冲增生向拼贴转变逐渐过渡。250~210 Ma(峰值244 Ma),在蒙古—鄂霍茨克造山带东侧额尔古纳—中蒙古地块主要形成斑岩型铜矿床,可能与蒙古—鄂霍茨克洋俯冲有关;以东地区,主要在大兴安岭南段和辽远地块形成斑岩型钼矿床,在张广才岭发育岩浆熔离型铜镍矿床,反映了古亚洲洋闭合后伸展环境。210~167 Ma(峰值170 Ma),在蒙古—鄂霍茨克造山带西侧乌兰巴托西北部发育造山型-斑岩型金矿床,其东侧额尔古纳地区形成斑岩型铜钼矿床,可能与蒙古—鄂霍茨克洋俯冲碰撞有关;在吉黑东部—张广才岭—小兴安岭—大兴安岭,发育斑岩型钼铜矿床和矽卡岩型铅锌钨金矿床组合,可能属于古太平洋板块向西俯冲成矿体系。155~100 Ma(峰值136 Ma),中亚造山带东部整体处于伸展环境;其中,155~120 Ma在额尔古纳地区主要发育浅成低温热液型银铅锌矿床和造山型金矿床,大The Eastern Central Asian Orogenic Belt（ECAOB）is located in the overlap region among Palo-Asian Ocean tectonic domain,Okhotsk Ocean tectonic domain,and Paleo-Pacific Ocean tectonic domain,and very rich in mineral resources.According to statistics and digital mapping of 201 available isotope ages,out of 1 200 ages,spatial-temporal distribution and tectonic settings of magmatichydrothermal ore deposits in the ECAOB are discussed.It＇s proposed that the mineralization began at Cambrian,and can be identified six distinct metallogenic stages,i.e.510-473 Ma,373-330 Ma,320-253 Ma,250-210 Ma,210-167 Ma,155-100 Ma.From 510 to 473 Ma（peak age at ca.507 Ma）,there developed hydrothermal vein and porphyry Fe/Cu/Au/W ore deposits which are scattered in the Beishan and the Great Xing＇an-Lesser Xing＇an-Zhangguangcai Ranges,and related to the subduction of PaleoAsian Ocean and the collision of micro-continents.From the Late Devonian to the Early Carboniferous（373-330）,super-large scale porphyry Cu-Au deposits formed in the Oyu Tologi of Southern Mongolia,and related to the subduction of Paleo-Asian Ocean.During the third mineralization stage（320-253Ma）,a small amount of porphyry Cu deposits and orogenic Au deposits developed in the south part of Great Xing＇an Ranges.Porphyry Mo poly-metallic deposits formed at 298 Ma firstly appeared in study area,representing an important change of tectonic setting,from the subduction accretion to the collage of plates.During the Triassic（250-210 Ma,peak age at ca.244Ma）,numerous porphyry Mo deposits were distributed in the Liaoyuan terranes and the South part of Great Xing＇an Ranges,whereas some magmatic separation Cu-Ni deposits formed in Zhangguangcai Ranges,which proposed that those deposits are controlled by post-orogenic extension setting involving the closure of the Palo-Asia Ocean Triassic porphyry Cu deposits in the Erguna-South Mongolia are related to the subduction of the Okhotsk Ocean.During the period of 210-167 Ma（peak age at ca.170 Ma）,orogenic-por

关 键 词：岩浆热液矿床 同位素年龄 时空分布 中亚造山带东部 

分 类 号：P611.11[天文地球—矿床学]