冀东地区是一个金矿聚集区,但与国内外的矿集区相比,冀东地区却"只见星星不见月亮或少见月亮",这可能是因为某些具有地区性特征的找矿标志尚未被人们所认识.本次工作采用SHRIMP锆石U-Pb法测得唐杖子金矿的花岗斑岩株的形成年龄为173Ma+2Ma,牛心山红色花岗岩的年龄为173Ma+2Ma,与峪耳崖岩体红色花岗岩的年龄174Ma+3Ma相吻合,同属中生代燕山早中期,应是同一岩浆活动的产物.如果金矿与该岩浆活动有关,那么这3个矿床就具有成因上的联系,即它们(也许包括更多的矿点)可能由一个热中心分异矿化形成,后经多次地壳活动形成目前的格局.%The eastern Hebei Province is well known for prospective gold deposits, while unlike other famous foreign gold deposits region, not yet any significant Au deposits are discovered, the reason can be that some regional ore exploration indicators have not been recognized so far. Through recent studies, zircon SHRIMP dating from granite rocks related to gold formation in Tangzhangzi and Yuerya granites complex are conducted, the author obtain two U-Pb ages, respectively 173 ±2Ma for porphyry granite in Tangzhangzi and 173±2Ma for red granite in Niuxinshan, which are in accordance to the result of red granite in Yuerya (174±3Ma), belonging to early or middle Mesozoic Yanshanian. It′s estimated that they are formed during the same magmatic activity. If the gold deposits are related to this magmatic event, then all these three deposited are probably formed by mineralization differentiation from same thermal-center and then underwent multi-phase crustal tectonic movement.
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