华北板块接触交代型铁矿成矿规律及成矿预测

接触交代型铁矿在我国铁矿床类型中占有较重要的地位。华北板块区接触交代型铁矿在我国该类型铁矿中,不论在探明储量和研究程度上均取得很大进展。目前本区该类型矿床的地质研究及找矿工作已近尾声,但仍有很多问题尚待进一步深入,新区的找矿工作有待于老区工作经验的借鉴。因此,进一步总结和提高认识仍有必要。本文将着重从区域和矿床成矿规律及预测成矿有望地区略加探讨。不正之处,请予指正。一、控矿围岩

THE METALLOGENIC REGULARITY AND PROGNOSIS OF THE CONTACT METASOMATICTYPE IRON ORE DEPOSITS IN NORTH CHINA PLATE AREA

This paper deals with ore-controlling country rock, ore field structure, ore deposit distribution regularity, metallogenic models and metalloge nic prognosis of the contact metasomatic-type iron deposits in western Shandong, both sides of Taihang mountain and Yanshan metageosynclinal district in North China plate area, placing an emphasis on the ore-con trolling function of the country rocks.The ore field is situated in the rift basin at the side of the rift valley belt.Yanshanian magmatic rocks are ore-forming parent rocks and the original magma is related to basic rocks or ultrabasic rocks.Three stages might be classified according to the intrusive sequence.Iron ores are associated with inter mediate-acidic(with some basic) rocks or intermediate-acidic (with some alkaline) rocks of early-middle stage, and Mo-, Cu-, Au-bearing hy-drothermal vein deposits commonly associated with alkaline rocks of late stage.Old latitudinal structures in basement might function as channels for magma.Neocathaysian tectonics of upper cover is rock-controlling structure.It is believed that the interlayer weak zone within the cover provides favourable space for magmatic intrusion.Magmatic body appears as a laccolith.The equidistant or grating distribution of the cover bed structure resulted from wavy transmission of the stress provides a helpful indication for the prognosis of ore deposits, and six prospects for exploration are thus suggested by the auther.