辽东五龙金矿周缘早白垩世花岗岩体侵位深度及其地质意义  

Emplacement Depth of Early Cretaceous Granitoid Intrusions in Periphery of Wulong Gold Deposit in Liaodong Peninsula and Their Geological Implications

作　　者：李建锋[1,2] 刘建民 胡国辉[1,2] 王伟 张琪琪[1,2] 张拴宏 Li Jianfeng;Liu Jianmin;Hu Guohui;Wang Wei;Zhang Qiqi;Zhang Shuanhong(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;Key Laboratory of Paleomagnetism and Tectonic Reconstruction,Ministry of Natural Resources,Beijing 100081,China;103 Brigade of Nonferrous Geological Bureau of Liaoning Province,Dandong 118008,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]自然资源部古地磁与古构造重建重点实验室,北京100081 [3]辽宁省有色地质局一〇三队,辽宁丹东118008

出　　处：《地球科学》2021年第5期1585-1596,共12页Earth Science

基　　金：国家重点研发计划项目(No.2018YFC0603802)。

摘　　要：早白垩世岩浆活动对辽东半岛五龙地区金矿形成可能具有明显的制约作用,并可能为含金流体提供了热源及动力.五龙金矿南、北早白垩世三股流岩体和五龙背岩体角闪石-斜长石温压计计算结果表明,这2个岩体角闪石结晶温度为640.8~757.4℃,对应岩浆的侵位深度为5.9~9.7 km.角闪石TiO_(2)-Al_(2)O_(3)图解表明,三股流和五龙背岩体岩浆源区为壳幔混源.三股流和五龙背岩体侵位深度的差异表明,晚白垩世晚期至早始新世和晚始新世至渐新世五龙地区发生的两期强烈的差异性隆升和剥露过程使五龙岩体、三股流岩体及五龙背岩体在研究区大面积出露,含金矿脉随着区域性隆升到达近地表.考虑到辽东半岛与胶东半岛的相似构造背景,认为五龙地区具有进一步金矿勘探的价值.Early Cretaceous magmatism in the Liaodong Peninsula is of great significance for the formation of Wulong gold deposit and probably provided the heat source and power for the gold-bearing fluid. Results from geothermobarometry of hornblendeplagioclase applied to the Early Cretaceous Sanguliu and Wulongbei granitoid intrusions, located in the north and south parts of the Wulong area respectively, demonstrate that hornblendes in the Sanguliu and Wulongbei granitoid intrusions crystallized at temperatures from 640.8 to 757.4 ℃ and the emplacement depth of the magma is from 5.9 to 9.7 km. On the TiO_(2)-Al_(2)O_(3) diagram, samples from the Sanguliu and Wulongbei granitoid intrusions plot in the area of mixed source of crust and mantle.The difference of the emplacement depth between the Sanguliu and Wulongbei granitoid intrusions indicates that the large areas of emergence of the Wulong, Sanguliu and Wulongbei granitoid intrusions were formed by the strong differential exhumation and denudation during the times from late Late Cretaceous to Early Eocene and from Late Eocene to Oligocene. Simultaneously, the gold-bearing veins reached the near surface by regional uplift. The Wulong area is worth further gold exploration considering that the Liaodong Peninsula has the similar tectonic settings with the Jiaodong Peninsula.

关 键 词：早白垩世 五龙金矿 角闪石-斜长石温压计 侵位深度 岩浆源区 矿床地质 

分 类 号：P61[天文地球—矿床学]