杨冲金红石矿床地质特征

位于河南新县的杨冲金红石矿床。主矿体长981m、最厚处225m、延深大于189m。矿石类型包括角闪石石榴石斜长石型片麻状、斜长石绿帘石型块状、石榴石角闪石型块状及角闪石石榴石型块状4种,以第1、3、4种为主,各类矿石分布于同一矿体的不同部位,矿石品位一般2.20%～5.88%。矿床规模属大型。矿石原岩为富钛高铁基性侵入岩,成岩过程中钛进一步富集;矿床发生了两次变质作用,第一次变质相属角闪岩相-榴闪岩相,第二次属角闪岩相,均与成矿关系密切;成矿后,微弱的热液活动使金红石进一步有所富集。从大地构造特征等分析,应有良好成矿远景。

GEOLOGICAL CHARACTERISTICS OF YANGCHONG RUTILE DEPOSIT

The major orebody of the Yangchong rutile deposit in Xinxian county, Henan is 981 m in length, 225 m in maximum thickness, and>189 min extension. Four ore types have been distinguished: homblende-gamet-plagioclase-typed, gneissoid, plagioclase-epidote-typed, massive, gamet-homblende-typed, massive, and homblende-gamet-typed. The first three types are relatively important relative to the fouth. Various ore types distribute at the different parts of the same orebody, grading from 2.20% to 5.88%. The deposit is proven large-sized; the ore protolith was composed of Ti-high, Fe-rich, basic intrusive rock, from which titanium was largely released and enriched during diagenesis. It was overprinted by two metamorphic events, which reached amphibolite-gamet diorite facies and amphibolite fades, respectively, linking closely with titanium mineralization. Hydrothermal activities, though very weak, of post-mineralization more favoured the enrichment of rutile. Characteristic tectonic environment allows the deposit to have better prospects for metallogenesis.