柏树岗金红石矿床含矿岩系地质特征

河南方城柏树岗金红石矿床含矿岩系主要由角闪(片)岩、变粒岩、斜长片岩、石英(片)岩及云母片岩组成、前者是主要含矿岩石。分为石英(片)岩、角闪(片)岩-云母斜长片岩、云母片岩-石英(片)岩三个岩性段,二段是主要含矿岩段。原岩为一套火山岩、正常沉积岩岩性组合。经历了两次变质作用,变质温压400～485℃、200～700MPa,变质时间416.1±0.5Ma,变质热液产生了少量细脉及脉岩。含矿岩系的形成变化是板块运动的结果。基性岩及基性岩质凝灰岩是钛的主要来源,变质作用是主要成矿作用。

GEOLOGICAL CHARACTERISTICS OF ORE-HOSTING ROCKS OF BAISHUGANG RUTILE DEPOSIT

The ore-hosting rocks of the Baishugang rutile deposit in Fangcheng county Henan are dominated by amphibolite (amphibole schist), leptynite, plagioclase schist, quartzite (quartz schist) and mica schist. The former lithologies, as main host rocks, may be classified into three lithological members: quartzite (quartz schist), amphibolite (amphibole schist)-micaceous plagioclase schist and mica schist- quartzite (quartz schist). The second lithological member, amphibolite (amphibole schist)-micaceous plagioclase schist, is the most important to mineralization, whose protolith comprised an assemblage of volcanic rock and normal sedimentary rock and lately, 461.1 ± 0.5Ma, was subjected to two metamorphic events at 400-485℃ and 200-700MPa, resulting in metamorphic hydrothermal solution leading to a little amount of vein lets and vein rocks. The ore-hosting rocks owed their formation and then modification to plate movement, the titanium was sourced from basic rocks and basic tuffs, and the metamorphic events were critical to titanium mineralization.