Abstract

Info

Title:: Main Controlling Factors of Hydrocarbon Accumulation and Prediction of Favorable Exploration Zone of Neogene in the Western Slope of Bozhong Sag

Author(s):: XU Chun-qiang; WANG De-ying; ZHANG Xin-tao; YANG Hai-feng; YANG Chuan-chao; Tianjing Branch of CNOOC China Ltd., Tianjin 300452, China

Keywords:: hydrocarbon accumulation; main controlling factor; Neogene; shallow exploration; oil source; accumulation period; fault; Bozhong sag

Abstract:: A series of breakthroughs has been made in petroleum exploration of Neogene in the western slope of Bozhong sag in recent years, which makes this area become favorable. On the basis of distribution and hydrocarbon source of Neogene in the western slope, the main controlling factors of hydrocarbon accumulation were summarized, and the favorable exploration zone was proposed. Researches on hydrocarbon source and distribution of Neogene of the western slope indicate that the oil and gas distribution is controlled by source rock development characteristics, fracture characteristics and trap types; in the west area, symbiotic sag, hydrocarbon source rocks and longterm activities of oil source faults are well developed, which provides a favorable condition for the formation of oil and gas reservoir in shallow strata; due to the lack of deep Shahejie Formation source rocks of fault, it is difficult for oil and gas migration to shallow, and is not conducive for the accumulation of oil and gas; these regions, which are close to subsag and fault belts, should be the preferable prospects in the exploration process of Neogene in the western slope of Bozhong sag, and more attention should be paid on faults which could be migration pathway and regions near subsag. Southwest part of the study area is the most favorable zone.