初论郯庐断裂的成藏成矿效应

郯庐断裂是多次活动的深达地幔的断裂带,在其形成与演化过程中伴随有不同类型矿产形成,古生代以来郯庐断裂性质由张裂-压扭-扭张变化,相应的岩浆活动由超基性、基性-酸性-基性、碱性演化,与之有关的矿产由金刚石、铬、镍、铜、铁等岩浆矿床→金、钼、钨、锡、铅、锌、汞、锑、银的热液矿床与石油与烃类气藏→金、银、石油、烃类气、非烃气藏及宝石矿床等演变。郯庐断裂两侧的成矿作用,表现出明显的阶段性、偏对称性、交叉性和两侧成矿的差异性特点,是郯庐断裂带本身纵横特点、郯庐断裂穿越地块性质以及与其交切的东西向褶断带性质联合控制的结果。郯庐断裂两侧不同部位、不同时期、不同类型矿产形成过程中,壳幔作用程度不同,地幔流体有不同程度的贡献,而强烈的壳幔交换作用导致的地幔流体和地壳流体的联合作用常是大规模热液矿床矿集区形成的必要条件。

EFFECT OF TAN-LU FAULT ON THE FORMATIONOF MINERAL DEPOSITS AND OIL-GAS FIELDS

The Tan -Lu fault is a multi-active fa ult zone,which may reach as deep as ma ntle.With the formation and evolution of the Tan -L u fault,different kinds of deposits and oil-gas fields have been formed.Since Palaeozoic Era,the character of the Tan -Lu fault zone changed from tension through compresso-shear to torsion-tension,the accompanying magmatism evolved from ultrabasic and basic through acidic to basic an d alkaline,and the related deposits a nd oil-gas fields revolved from magm atic deposits(such as diamond,Cr,Ni,Cu,Fe ect)through hydrothermal deposits(such as,Au,Mo,W,Sn,Pb,Zn,Hg,Sb,A g)and oil-gas fields to Au,Ag,gem deposit s and petrol,hydrocarbon,non-hydr ocarbon gas fields.The mineral-ization related to the Tan -Lu fault z one may be characterized by obvious s tages,symmetry-like,intersectin g and differences between the two sides of the fault zone,which may be contr olled by longitudinal-transversal features of the Tan -Lu fault,the nature of the massif which the Tan -Lu fau lt cuts through and the nature of the folds trending EW and crosscut ing by the Tan -Lu fault.With the evolution of the Tan -Lu fault and the crust-mantle interactions to di fferent extent,the mantle-derived fluids may have different contribut ions to the formation of the different kinds of deposits and oil-gas fields,and t he combined action of mantle-derived and the Earth's crust-derived fluids caused by int ense crust-mantle interactions may be essential condition for the formation of the concentrated hydrothermal deposits.