摘要
钠长石岩分布不太广泛 ,研究程度较低。通过研究 ,本文将钠长石岩分为接触带型、层状型、顺层角砾岩型、脉型及岩体型 5类。其中以层状钠长石岩型分布较广 ,意义较大。层状及与之紧密相伴的顺层角砾状钠长石岩有特定的矿物组合、化学成分及岩石组合 ,层状及角砾状钠长石岩产在一定的地层层位中 ,形成于特殊的沉积环境 ,且有一定的时空分布规律 ,并伴有特殊的 Au,Cu,Pt- Zn- Ag,Ba,Fe,B等矿产。因此笔者认为钠长石岩系特定地质条件下的产物。目前对其成因有岩浆岩、热液交代 +充填、热水沉积等不同认识 ;热水来源也有岩浆水、地下水、变质水等多种观点。本文作者认为层状及角砾状钠长石岩为热水沉积形成的 ,成岩流体属含 Na- Mg- Si- Al± Fe,Ba,B的 HCO3- ,CO32 - 碱性溶液 ,成岩物质来自基底富钠岩石。
Albitite may be divided into contact zone,stratiform,breccia,vein and intrusive mass types.Stratiform and accompied breccia ablitite is characterized by special mineralogical associations,chemical components and petrographic assemblages.They are distributed in particular stratigraphic section which is controlled by marine sedimentary environment in geosyncline during Archean to Paleozoic.Au,Cu,Ag,Pb,Zn,Ba,Fe and B deposits are developed in stratiform and breccia albitite.There are some different views on the genesis of albitite:magmatic rock,hydrothermal metasomatism+filling and hot water sedimentation.Magmatic,superficial and metamorphic fluids are inferred by researchers.This paper hold hot water sedimentation genesis of both stratiform and breccia albitite,which are formed by Na Ca Al Si±Fe,B,Ba bearing alkaline HCO 3 -,CO 3 - solution.The rock forming materials are derived from Na rich rocks in the basement.
出处
《矿物岩石》
CAS
CSCD
北大核心
2001年第2期16-21,共6页
Mineralogy and Petrology
基金
国家自然科学基金项目"热水沉积钠长石岩型金矿床的形成机制"(项目编号 49772 114 )资助
