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中国东部(贺兰山、六盘山、龙门山以东地区)夕卡岩铁矿成矿带,为环太平洋成矿带的重要组成部分.具有矿床多、分布广、成群成带出现,结状相对富集特点.夕卡岩型铁矿系指那些成矿作用发生在侵入体与围岩的接触带或受接触带影响的一定范围内,在气—热液作用下,主要以交代方式形成的铁矿床,这类矿床与夕卡岩在空间上、时间上、形成机理上有密切的成因联系.作者从以下几个方面的讨论,来探讨成矿富集问题.(一)夕卡岩铁矿的区域分布严格受不同性质的大地构造单元(地槽、地台)控制,矿化表现以华北地台为中心的南北对称分带规律.成矿带自北向南为东北地槽成矿带、燕辽过渡区成矿带、华北地台成矿带、长江中下游过渡区成矿带、东南地槽成矿带.五个构造成矿带内的岩浆建造、沉积建造与金属矿化组合有显著的差异和对称性分布如表1.成矿岩浆岩由中心(地台)区向南、北进入地槽依次从中基性(闪长岩组合)→过渡区中酸性(花岗闪
The skarn iron ore belt in eastern China (Helanshan, Liupan Mountain, east of Longmenshan) is an important part of the Pacific Rim metallogenic belt, with many deposits and widely distributed, Enrichment characteristics. Skarn type iron ore refers to those mineralization occurred in the invaded body and the surrounding rock contact zone or affected by the contact zone within a certain range, in the gas - hydrothermal, mainly formed by the way of account Iron deposits, which have a close genetic relationship with skarn in terms of space, time and formation mechanism, are discussed in the following aspects to explore the issue of metallogenetic enrichment. The regional distribution of iron ore is strictly controlled by different tectonic units (troughs and terraces), and the mineralization is characterized by the north-south symmetrical zonation along the north China platform. Belt, the Yanliao transition zone metallogenic belt, the North China platform metallogenic belt, the middle and lower reaches of the Yangtze River transitional zone metallogenic belt, southeast of the slot mineralization zone .Morpholitic belt within the five structural mineralization, sedimentary construction and metal mineralization There are significant differences in composition and symmetry distribution as shown in Table 1. Mineralization magma From the center (platform) region south, north sequentially into the trough from basic (diorite composition) → transition region acid (granodiorite