鲁西地区太古宙绿岩带硫铁矿床地质特征及成矿机制

鲁西地区新太古代雁翎关组由科马提岩、角闪质岩石、变粒岩和含铁石英岩等组成 ,其原岩为一套超镁铁质镁铁质火山熔岩及火山碎屑沉积的表壳岩建造 ,经历了三期区域变质作用 ,变质程度达低角闪岩相 ,是华北地台上一个典型的绿岩带。鲁西花岗岩绿岩带中分布有大小黄铁矿脉数十条之多 ,呈层状、透镜状或脉状沿片麻理方向展布 ,硫品位 3 .79%～ 3 1.6% ,伴生有用组分Fe、Ni、Ag等。通过对绿岩、矿体和矿石特征、S、Fe分布及变质成矿作用等方面的研究 ,证实绿岩中含有丰富的S、Fe、Ni等造矿元素 ,认为绿岩既是赋矿岩石亦是矿源层 ,矿床属变质热液叠加的变质火山沉积型硫铁矿床。

GEOLOGICAL CHARACTERISTICS AND MINERALIZAINGMECHANIZM OF PYRITE DEPOSITS IN ARCHAEAN GREENSTONE BELT IN THE WESTERN SHANDONG REGION

The late Archaean yanlingguan formation in west Shandong is a typical greenstone belt on the north China platform,it is composed of Komatiite,Hornblende, Leptynit,ferruginous Quartzite and so on,their protolyte is a series supercrust formation of ultramafic-mafic lava rocks and pyroclastic sedimentary rocks,which had been taken on three-epoch of regional metamorphism and their metamorphic grad reach low-pressure amphibolite facies. Dozens of the pyrite-ore bodies which have different scale distribute in west Shandong granite-greenstone terrane with wein,len and stratoid shapes,and which stretch out as gneissosity as direction.The ore,mainly hosted in pyrite-amphibolite,sulphtenor in the ore usually are from 3.79×10-2 to 31.6×10-2,associated mineralizer are Fe,Ni,Ag etc.According to the above studes of greenstone,ore and bodies,metamorphic metallization,result show that greenstones contain rich mineralizer of the S?Fe?Ni etc.The greenstones are both container rock and source bed.The deposits are referred to as pyroclastic-sedimento-metamorphic type deposit that is telescoped by the metamorphic hydrothermal.