摘要
南秦岭铧厂沟金矿床位于勉略缝合带以南的逆冲推覆带内,矿体呈透镜体或脉状产于新元古界蚀变细碧岩及泥盆系灰岩中,受控于近EW向叠瓦状逆冲断层及韧脆性剪切带。为了准确厘定其成矿时代,对矿区蚀变细碧岩型矿石和含矿石英脉中的铬云母进行了年龄测定。2件铬云母样品的^(40)Ar/^(39)Ar坪年龄分别为209.4±2.3 Ma和211.5±2.5 Ma,相应的等时线年龄211.4±3.6 Ma和215.3±3.9 Ma,与坪年龄在误差范围内一致。因此,铧厂沟金矿床的成矿年龄为212~209 Ma。结合铧厂沟金矿床的大地构造位置、矿床地质特征及成因类型,推测铧厂沟金矿床形成于扬子板块与秦岭微板块的碰撞过程,其成矿年龄代表了两板块发生碰撞的下限。
The Huachanggou gold deposit in Shaanxi province is located at the south of Mianlue Suture Zone. The ore bodies, which are mainly controlled by a series of EW trending ductile-brittle shear zones and reverse faults, are hosted in the spilite and limestone. To constrain the metallogenic age, fuchsite 40Ar/39Ar geochronological analyses were carried out. Two fuchsite samples from the gold bearing quartz veins and altered spilite ore yielded 40Ar/39Ar isotopic plateau ages of 209.4±2.3 Ma and 211.5±2.5 Ma, respectively, representing the mineralization age of gold polymetallic sulfides. By summarizing the characteristics of ore geology and the geotectonic location, it can be inferred that the Huachanggou gold deposit was formed during the collision between the Yangtze Block and Qinling micro Block which might have been took place before 209 Ma.
出处
《大地构造与成矿学》
EI
CAS
CSCD
北大核心
2017年第2期315-324,共10页
Geotectonica et Metallogenia
基金
国家自然科学青年基金(41502070
41403032)
全国危机矿山接替资源找矿项目(20089934)资助
