WANG J G, ZHANG D Z, SHI J P, et al. Petroleum characteristics and resource potential evaluation of peripheral depressionsin the Bohai Bay Basin［J］. Journal of Henan Polytechnic University（Natural Science）, doi: 10.16186/j.cnki.1673-9787.2024040018

Received：2024-04-11

Revised：2024-09-19

Online：2024-10-28

Petroleum characteristics and resource potential evaluation of peripheral depressions in the

Bohai Bay Basin (Online)

WANG Jianguang¹, ZHANG Dazhi¹, SHI Jipeng¹, LIU Haitao², ZHANG Zhiyuan¹, ZHANG Hang¹, LI Ting¹, HE Shan¹

（1.The First Geological Exploration Institute of Henan Provincial Bureau of Geology and Mineral Exploration and Development, Zhengzhou, 450000, Henan, China;2.PetroChina Research Institute of Petroleum Exploration & Development, Beijing, 100080, China）

Abstract: Previous studies on the Bohai Bay Basin have mostly focused on the main depression, neglecting the peripheral depressions, resulting in limited understanding. Objectives To further clarify the hydrocarbon-bearing characteristics and the distribution of resource potential in the peripheral depressions of the Bohai Bay Basin. Methods A comparative analysis of the hydrocarbon-bearing characteristics of the peripheral depressions in the Bohai Bay Basin was conducted, based on geological structures, subsidence types, and reservoir-forming assemblages. Furthermore, a graded evaluation standard for the resource potential of these peripheral depressions was established, taking into account the conditions of hydrocarbon source rocks, reservoir rocks, traps, hydrocarbon preservation, and the spatial-temporal matching relationship between trap formation and hydrocarbon generation peak. This standard was then applied to conduct a graded evaluation of the resource potential of the peripheral depressions in the Bohai Bay Basin. Results Hydrocarbon-rich depressions are mainly large-area, deeply buried, dustpan-shaped Type II depressions, while peripheral depressions are mainly small-area, dustpan-shaped Type I depressions with relatively poor hydrocarbon-bearing conditions; Peripheral depressions are generally early-stage intense faulted depressions with poor hydrocarbon generation capacity and low hydrocarbon enrichment; Peripheral depressions often contain one to two relatively oil-bearing reservoir-forming assemblages, while hydrocarbon-rich depressions commonly have three reservoir-forming assemblages. The Wuqing and Yanshan depressions are classified as Type I depressions with significant resource potential and good exploration and development prospects, serving as target areas for future oil and gas reserve growth. The Laoting, Dachang, Nangong, Baoding, Shijiazhuang, and Jianhe depressions are classified as Type II depressions with average resource potential and certain exploration and development value. The Wuqiao, Beijing, Xushui, and Changli depressions are classified as Type III depressions with poor hydrocarbon accumulation conditions, small resource potential, and great difficulty in achieving exploration discoveries. Conclusions The peripheral depressions of the Bohai Bay Basin harbor abundant residual hydrocarbon resources, presenting favorable conditions conducive to the formation of substantial hydrocarbon reservoirs. Through meticulous research endeavors, these depressions hold immense potential to evolve into pivotal successor domains for the future landscape of hydrocarbon exploration.

Key words: Bohai Bay Basin; peripheral depression; hydrocarbon bearing characteristics; conditions for hydrocarbon accumulation; source rock; resource potential

CLC: TE122