摘要
伊春地区晚三叠世-早侏罗世花岗岩分布广泛,岩石主要类型有似斑状二长花岗岩-二长花岗斑岩、正长-碱长-碱性花岗岩等,在该地区已发现的与早中生代花岗岩侵入密切相关的铁多金属及金等大小矿床的成因类型主要为斑岩型、矽卡岩型、矽卡岩-热液型、岩浆热液型、浅成低温热液型等,成岩、成矿时代为晚三叠世-早侏罗世(U-Pb锆石LA-ICPMS年龄为191～225Ma之间),成矿时代略晚于成岩时代。依据早中生代花岗岩岩石类型、时代、构造-岩浆演化、花岗岩成因类型及其陆陆碰撞不同阶段构造背景下的成矿作用特征,将矿床成矿系列划分为:碰撞-碰撞后构造转换型似斑状二长花岗岩-二长花岗斑岩Mo-Pb-Zn-Fe-W-Au(Ag)成矿亚系列和碰撞后崩塌型正长-碱长-碱性花岗岩Fe-Mo-Pb-Zn-NbTa成矿亚系列,其成矿元素、矿化强度、类型等成矿特征上的差异,可能与源区物源、壳幔混合程度、混合比例和侵位深度,以及与成矿构造背景不同等综合因素有关。
The late Triassic to early Jurassic granites are widely distributed in the Yichun area, Heilongjiang Province, which are dominated by por- phyaceous monzonitic granite, monzonltic granite porphyry, syenogranite, alkali-feldspar granite and alkali granite. And the discovered iron-plolymetallic deposits and gold deposits related to these rocks are mainly of porphyry, skarn, skarn-hydrothermal, magmatic hydrothermal and epithet^ml hydrothermal types. The major rock-forming and ol^-forming ages are late Triassic to early Jurassic （ U-Pb zircon LA-ICPMS age of 191 - 225Ma）, and the ore-forming age is slightly later than the metallogenic epoch. This paper studies the major rock types, geologic ages, teetono-magmatic evolution, genetic types of the early Mesozoic granites and mineralization characteristics of different continental-collision stages. We divide the metallogenic series into two metallogenie subseries： the Mo-Pb-Zn-Fe-W-Au（Ag） metallogenic subseries of porphyaeeous monzonltic granite-monzonitic granite porphyry of continental collisional- postcollisional structural transposition and the Fe-Mo-Pb-Zn-N]c^Ta metallogenic subseries of syenogranite-alkali-feldspar granite-alkali granite of postcolli- sional collapse episode. These two metallogenic subscries differ in metallogenic features, i. e. , ore-forming elements, mineralization intensity and types. And these differences are related with granite source areas, the degree of crust-mantle mixture, mixture ratio, granite emplacement depth and metallogenic tectonic background.
出处
《地质与勘探》
CAS
CSCD
北大核心
2013年第1期28-38,共11页
Geology and Exploration
基金
中国地质调查局基础地质调查项目(200313000035)
