青海省白日其利金矿构造演化特征及找矿意义

白日其利金矿位于青海省北昆仑岩浆弧带南侧,为一典型构造蚀变岩小型金矿。区内构造-岩浆活动强烈而复杂,主要含矿构造既经历了元古代—中生代大规模岩浆上侵导致向南的推覆作用,又经历了新生代青藏高原抬升拉张环境下导致向北的滑脱作用,显示出张扭性和压扭性双重特征。结合地表观察和音频大地电磁测深反演结果,综合分析认为,研究区主要含矿构造(F₁)地表产状为NE陡倾,深部为SW陡倾,金矿(化)体极可能位于低阻异常带且构造显示张扭性特征膨大部位,其深部找矿前景较大。

Tectonic evolution feature of Bairiqili Au deposit in Qinghai province and the significance to ore prospecting

Bairiqili Au deposit is a typical small altered cataclastic rock type Au deposit located in the south of northern Kunlun magmatic arc belt in Qinghai province. The area where the Au deposit occur is characterised by transtensional and compressional structure with strong and complex tectonic-magmatic activity. The ore-bearing structure was exposed to large scale upward intrusion of magma during proterozoic-Mesozoic period leading to southward over-thrusting and exposed to the Qinghai plateau uplifting and the northward detachment during Cenozoic period. Based on observations at surface and inversion data of audio magnetotelluric sounding survey it is concluded that the main ore-bearing structure F₁ dips steeply to NE at surface and to SW to depth. Au ore (mineralization) body is possibly located at low resistivity anomaly and transtensional dilated zones and the ore prospecting is potential to depth.