【作者】 张维萍；

【导师】 赫英；

【作者基本信息】 西北大学 ， 地球化学， 2007， 博士

【摘要】 本文对华北地块北缘河北大麻坪不同类型的深源包体以及辽宁、吉林等地的一些橄榄岩包体中的金、钼、钨含量进行了较系统的分析。在此基础上运用比较矿床学的思维和研究方法，通过橄榄岩包体常量元素、微量元素、REE及PGE元素与金含量的相关性的分析以及华北地块北缘与南缘、华北地块东西部、以及不同类型深源包体中金、钼、钨等含量与分布的比较研究取得了以下新的认识和进展：1．地幔橄榄岩包体中的金早期主要赋存于单斜辉石中，当包体中CaO的含量大于2％时，地幔岩包体大多有较高的金含量。地幔橄榄岩包体中金含量的高低与部分熔融程度有关。2．华北地块北南两缘地幔岩包体成矿元素的分布是不均一的。其中Ni、Fe含量明显表现为北缘高南缘低，而Au、Mo(W)含量则明显表现为南缘高北缘低。反映了地幔岩包体中的Ni、Fe、Au、Mo含量高低与华北南北两缘Ni、Fe、Au、Mo成矿情况基本是耦合的；地幔岩包体中Ni、Fe、Au、Mo等含量的高低对地壳矿产分布有指示意义；地幔岩包体中Ni、Fe、Au、Mo等含量的高低受控于地幔部分熔融程度和Ni、Fe、Au、Mo等地球化学相容性的差异。3．华北地块北缘的岩石圈地幔在部分熔融程度和交代作用上具有不均一性。其中前者东西差异不明显，却与岩石圈地幔的金含量有关系，而后者比较鲜明，但却与岩石圈地幔的金含量关系不明显。4．Au在各类深源包体中的富集顺序为：二辉岩包体≥二辉橄榄岩包体＞镁铁质麻粒岩包体≥寄主玄武岩＞长英质麻粒岩包体；Mo在各类深源包体中的含量顺序为：镁铁质麻粒岩包体，寄主玄武岩＞长英质麻粒岩包体＞二辉岩包体≥二辉橄榄岩包体；W在各类深源包体中的含量顺序为：长英质麻粒岩包体＞镁铁质麻粒岩包体≥寄主玄武岩＞二辉岩包体≥二辉橄榄岩包体。伴随壳幔演化和分异金、钼、钨分别富集于岩石圈地幔→下地壳→中、上地壳等不同层次的岩石圈，这是地壳中金、钼、钨矿床和矿床集中区形成与分布的重要原因。5．镁铁质麻粒岩包体中的金含量高于新生代寄住玄武岩中的金含量，暗示中生代中国东部金的成矿大爆发与当时富金岩石圈地幔的消耗有关系；而镁铁质麻粒岩包体中的钼含量高于新生代寄住玄武岩中的钼含量，暗示中生代中国钼的成矿大爆发与岩石圈地幔消耗过程的玄武岩浆作用也有关系。6．金、钼、钨在二辉橄榄岩包体、二辉岩包体、镁铁质麻粒岩包体、长英质麻粒岩包体及其寄主玄武岩中含量的差异性，不同地区地幔岩包体中的金、钼、钨含量的差异性及其相应的地壳中金、钼、钨矿床分布的差异性，与岩石圈组成、分异演化及金、钼、钨的地球化学性质有关。更多还原

【Abstract】 Gold, molybdenum and tungsten contents of deep source xenoliths of the different types from Wanquan of Hebei Province and peridotitic xenoliths from Liaoning Province and Jilin Province in the North margin of North China platform have been systematically analyzed. In this paper, by ideas and methods of comparative Geology of mineral deposits on the basis of systematic analysis of relationships for the gold content with major element, trace element, REE and PGE to the peridotitic xenoliths and comparative research on the distribution of gold, molybdenum and tungsten contents of north margin with south margin, eastern with western of North China platform and deep source xenoliths of the different types, some conclusions can be follows:1. In the mantle peridotite xenoliths, golden may be mainly in the clinoenstenite. While CaO content of peridotite xenoliths exceeds 2%, peridotite xenoliths have a relatively large component gold. Gold contents of the mantle peridotite are concern with the degree of partial melting of mantle.2. Ore forming elements in mantle peridotite xenoliths on the North China platform north margin (Damaping of Heibei Province ) and South margin (Linqu of Shandong Province) are inhomogeneous. It is obvious that contents of nickel, iron in mantle peridotite xenoliths on the North China platform north margin are higher than on the North China platform South margin’s and gold, molybdenum contents in mantle peridotite xenoliths on the North China platform South margin are higher than on the North China platform north margin’s. The contents of Ni, Fe, Au, Mo of the samples mantle-derived xenoliths from southern margin and northern margin of Northern China ( Shandong Province and Liaoning Province) are coupled with the basic metallogenic Provinces. It is considered that the Ni, Fe, Au, Mo contents of mantle-derived xenoliths may be indicator the distributions of concentrated districts in the crust. The contents of Ni, Fe, Au, Mo in mantle peridotite xenoliths are controlled degree of partial melting of mantle and their difference of geochemical properties.3. The lithosphere mantle on the north China platform north margin is inhomogeneous spatially in the degree of partial melting and the metasomatos. In which difference of the former is not obvious, but it is concern with gold content in lithosphere mantle. The difference of the latter is quietly bright, but it is not concern with gold content in lithosphere mantle.4. The order of Au concentrates of xenoliths from deep source is: pyroxenolites≥pyroxenite xenolith> mafic granulite xenolith≥basalt> felsic granulite xenolith. The order of Mo concentrates of xenoliths from deep source is: mafic granulite xenolith, basalt>felsic granulite xenolith> pyroxenolites≥pyroxenite xenolith. The order of W concentrates of xenoliths from deep source is: felsic granulite xenolith > mafic granulite xenolith, basalt > pyroxenolites≥pyroxenite xenolith. With evolvement and differentiation of mantle and crust. Au is rich in lithosphere mantle, Mo is rich in lower crust, and W is rich in middle and high crust. It caused Au, Mo and W deposits and their deposits-concentrated districts in crust.5. Gold content of mafic granulite xenolith is higher than gold content of basalt indicate that erupt of gold mineralization in Mesozoic in Eastern China is concern with depleteing of lithosphere mantle of rich gold. Molybdenum content of mafic granulite xenolith is higher than molybdenum content of basalt indicate that erupt of molybdenum mineralization in Mesozoic in Eastern China is concern with magmatism in the period of depleting of lithosphere mantle.6. The difference of gold, molybdenum and tungsten content among xenoliths from deep source and their host basalt, among mantle peridotite xenoliths from different locations and difference distribution of gold, molybdenum and tungsten districts in China is related to the mantle source of lithospheric mantle, the Crust evolution and the geochemical properties of gold, molybdenum and tungsten.更多还原