Abstract:

 The metallic ore deposits closely associated with hydrocarbon reservoirs in sedimentary basins mainly include the Mississippi Valleytype (MVT) PbZn deposits, the sandstoneand shalehosted CuU deposits, the sulfide deposits in black shales, and the sedimentary rockhosted AuSbAsHgTl deposits. The intimate association suggests a genetic linkage between metallization and hydrocarbon accumulation. In many MVT PbZn deposits and sandstone/shalehosted Cu deposits, crude oil and its derivatives predate metallization and may have provided reduced sulfur directly to the ore system or acted as reductant facilitating the reduction of sulfate. Under other circumstances, metals in some lowtemperature hydrothermal ore deposits, especially in sedimentary rockhosted Au, As, Hg, Sb and Tl deposits, may originate, transport and precipitate along with hydrocarbons, suggesting simultaneous metallization and hydrocarbon accumulation. The metallic ore deposits having different coupling relationships with hydrocarbons show different characteristics. The basinal fluids associated with metallization and/or reservoir formation include hydrocarbonrich organic fluids, metalrich aqueous fluids, and both hydrocarbon and metalrich organic oreforming fluids. Metallization, hydrocarbon accumulation and their coupling relationship in a sedimentary basin may be governed by the evolution of these fluids. The intimate association between ore deposits and hydrocarbon reservoirs and the similarity in process and mechanism for metallization and reservoir formation make it possible to carry out the coordinative exploration and comprehensive forecast of both metal and oilgas resources in sedimentary basins.

Key words: metallic ore deposit, hydrocarbon reservoir, coupling of metallization and reservoir formation, basinal fluid, sedimentary basin