福建德化杨梅地区金矿成矿地质条件和矿床成因

MINEROGENIC ENVIRONMENT AND GENESIS OF GOLD DEPOSITS AT YANGMEL REGION,DEHUA, FUJIAN PROVINCE

本文分析研究了德化杨梅地区金矿成矿地质条件，矿床主要地质和地球化学特征以及矿床成因等。结果表明，德化杨梅地区是一个金的高背景地球化学场．为成矿提供了物质基础，金矿床、矿点明显地受NE、NW向断裂及其交叉复合部位控制，与成矿有关的侵入岩—次火山岩主要是燕山期的石英闪长岩、花岗闪长斑岩和花岗斑岩；金的矿化类型主要为含金石英脉型、含金石英—硫化物型及破碎蚀变岩型；区内金矿成因类型主要为次火山热液型和岩浆热液型两类。

Yangmei region in Dehua is located at the medium section of Zhouning hua an upwarping faulted belt in eastern volcanic graben be1t of Fujian province, crossing position of Donghua-Daming foundational upwarping belt and Yongtai-Dehua volcanic eruption belt. There are more than ten gold deposits or mineral occurrences in this region which gold geochemical set-ting is high. Ore beds occur mainly at Middle Proterozoic Subera strata. Changlin formation and Nanguan formation of upper Jurassic period of Mesozoic. The gold deposit cormineral oc-currences are controlled by faults striking NE. NW and their transportatioris. This research shows the closely relation with magmatite-subvolcanic rock in Yanshan period and gold miner-alisation. Minerogenetic element mainly come from base metamorphic rocks in Middle Protero-zoic Subera, partly from volcanic intrusive massif in Yanshan period. Minerogenetic fluid. is a kind of low salinity and density mixed solution which consists of meteoric water and magmatic water. Minerogenetic temperature varied between 140℃ and 250℃. There are three types of gold mineralized bodies in this region, i. e. auriferous quartz vein type, auriferous quartz-sulfide type and kataclastic-altered rock type. Genesis of gold deposits Yangmei region are composed of subvolcanic low temperature hydrothermal deposits and magmatic hydrothermal deposits.