摘要
西滩金矿床主要赋存在下石炭统阿奇山组的中酸性火山岩－火山碎屑岩中，典型蚀变矿物包括绢云母、冰长石、玉髓、绿泥石、浊沸石、水白云母等。流体包裹体和稳定同位素研究表明：δＤ＝－１１９．４‰～－９０．２‰，δ１８ＯＨ２Ｏ＝－１２．７４‰～－１．６５‰，δ３４Ｓ＝０．１１‰～２．３１‰，成矿温度集中于１５０～２００℃，含盐度很低（０．８‰～６．７‰），成矿压力为２．６８×１０７～３．２６×１０７Ｐａ，ｐＨ值平均为６．７，由此推断成矿流体以大气降水为主，成矿物质具深源性，直接来自赋矿火山岩。
The Xitan gold depsoit is mainly occured in the intermediate acid volcanic rock and pyroclastic rock of Lower Carboniferous series Aqishan Formation(C 1 a ).Its typical altered minerals include sericite,adularia,chalcedony,chlorite,laumontite,hydromuscovite and so on.Some studies of the fluid inclusions and stable isotopes show that:the value of δD is -119.4‰ to -90.2‰ ,δ 18 O H 2O is -12.74‰ to -1.65‰,δ 34 S is 0.11‰ to 2.31‰ ,the ore forming temperature and pressure is 150 to 200℃ and 2.68×10 7 to 3.26×10 7 Pa respectively, and low middle salinity(0.8 to 6.7 wt‰ Nacl),the mean value of pH is 6.7.Based on above studies,we suppose that the ore forming fluid is mainly meteoric water,the ore forming material has a deep source characteristics and is directly derived from induced volcanic rock of the uppper mantle or lower crust.As a result,it should be a kind of adularia sericite type epithermal gold deposit according to classification of P.Heald et ,al.
出处
《新疆地质》
CAS
CSCD
1999年第1期2-8,共7页
Xinjiang Geology
基金
国家"305"项目
