山西灵丘支家地银矿地质特征

Geological Characteristics of Zhijiadi Silver Deposit in Lingqiu,Shanxi

支家地银矿位于华北地台北部，燕山断块涞源块隆与五台块隆的过渡地带，太白巍山北侧。银矿体受隐爆角砾岩筒内部构造及其边部构造控制，呈脉状斜列产出。区内已查明１０个银矿体，主矿体以盲矿体为主。成矿温度２５０～３５０℃，成矿压力为１８０×１０￣５Ｐａ，盐度为０．９２％，矿化度４２．４ｇ／ｔ，ｐＨ值为７．５７，Ｅｈ值为—０．７７。燕山期石英斑岩是主要矿源岩。隐爆角砾岩筒构造既是导矿构造，又是储矿构造。该矿床属于与次火山岩有关的中低温热液矿床。

Zhijiadi silver deposit is regionally situated in the transtional belt of Laiyuan uplift andWutai uplift,the north part of North China Platform,and locally it lies to the north of calderaof Taibaiweishan. Silver orebody is controlled by internal and marginal structures of crypto-explosion breccia pipe,and occurs as veins in oblique lines.Now ten silver orebodies havebeen discovered in the region, and the main ones are blind.The ore-forming temperature is250℃～335℃,pressure is 180 ×10￣5 Pa,salinity is 0.92%,degree of mineralization is 42.4g/t,pH value is 7.57,Eh value is─0.77.The main source rock is Yanshanian quartz por-phyry. The crytoexplosion breccia pipe is considered as the derivative passageway for ores,and ore accumulation as well.The deposit belongs to low-to-moderate hydrothermal type,and bears relationship with subvolcanic rock.