摘要
笔者近年在广西大厂锡矿泥盆纪地层中发现了中基性火山岩,这一发现对解释有关大厂锡矿床的形成机制和找矿研究具有重要意义。本文详细报道了新发现的火山岩的地质特征和岩石学特征,并初步探讨了火山岩与成矿作用之间的关系。显微镜下薄片鉴定显示该火山岩主要为玄武岩、安山岩类岩石,同上下围岩呈整合接触关系,具有纹层条带等典型的沉积构造特征,其产出层位的上下围岩含有大量竹节石等海相化石,应为海相喷发环境。矿化特征分析认为,矿石和层状火山岩之间关系更为密切,矿石对于层状火山岩具有一定的继承性和一致性关系,成矿物质来源可能与火山作用有关。推测该矿床为海相火山-喷流热水沉积-后期叠加改造成因。
The discovery of the intermediate and basic volcanic rocks in recent years in the Devonian strata in Dachang Guangxi has important significance in the explanation of the tin ore formation mechanism and the prospecting research.The authors analyzed its volcanic output characteristics,petrology and rock geochemistry and explored the relationship between the volcanic rock and the mineralization.The results show that the volcanic rocks are mainly basalt and andesite.The volcanic rocks are in conformable contact with the surrounding upper and lower rocks,with a lot of classic sedimentary structure characteristics of laminations and stripes,and the output position of the volcanic rocks contains a lot of marine fossils of tentaculitoid.The above evidence indicates that the eruption environment of the volcanic rocks is sea facies.The analysis shows that the ore is closely related to the layered volcanic rocks and shows consistency and continuity with the layered volcanic rocks,and ore sources may be related to the volcanism.It is concluded that the ore deposits in the study area should be of the type of marine volcanic-sedimentary exhalative hot water plus later superposition and alteration.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2012年第1期73-78,共6页
Acta Petrologica et Mineralogica
关键词
中基性火山岩
泥盆纪
广西大厂
锡矿床
SEDEX
intermediate and basic volcanic rocks
Devonian
Dachang in Guangxi
tin deposit
SEDEX
