Research of the Relationship between Characteristics of Carbonate Fracture-cave Unit and Fluids Producing Status-a Case Study in Well Block ZG7 in North Slope of Tazhong Uplift

摘要

Carbonate reservoir is one of the main controlling factors of hydrocarbon accumulation. But the exploration proved that high-quality reservoir and commercial hydrocarbon flow had no absolute corresponding relationship, high-quality reservoir just was the necessary condition of hydrocarbon accumulation. It was found that local construction highs had an important control function to hydrocarbon accumulation. So it has a realistic guiding significance to exploration that enhancing the detailed study on carbonate fracture-cave unit. This paper selected Well Block ZG7 with complex oil-water relationship as a case, and comparative analyzed the structural position, structural characteristics, reservoir characteristics and fluid producing status before and after acid fracturing. It indicated that structural position of fracture-cave unit had a crucial control function to the fluid property in it, whose high accumulated hydrocarbon and the low was water commonly. The structure of facture-cave unit had a close relationship with the fluid producing status, which differed from the variation of fracture-cave unit structure. Carbonate reservoir and local construction were the important controlling factors of hydrocarbon accumulation, under the background of high-quality reservoir, local structures and structural highs were the favorable accumulation areas.