关键词: 全油气系统, 要素, 演化, 序列分布, "六图一表", 齐家—古龙凹陷, 青山口组

Abstract: Although the Whole Petroleum System theory has gained substantial attention, an effective evaluation and characterization framework is still lacking. Following the core concept of "element-evolution-distribution", a research framework for the Whole Petroleum System was established. Taking the Whole Petroleum System of Qingshankou Formation in Qijia-Gulong sag of Songliao Basin as the study case, this paper systematically elucidates its evolutionary processes and distribution patterns, and develops a characterization system comprising six maps and one table, i.e., comprehensive static element map, burial history map, hydrocarbon accumulation event map, hydrocarbon ordered distribution map for key strata, profile distribution map, planar distribution map, and hydrocarbon summary table. The main findings are as follows. (1)The "element-evolution-distribution" integrated research concept was systematically proposed. Taking the Qingshankou Formation in Qijia-Gulong sag as a representative case, a Whole Petroleum System research framework suitable for continental basins was established, which provides a paradigm for studying the Whole Petroleum System in comparable geological settings. (2)The dynamic evolutionary process of conventional and unconventional reservoirs in the Whole Petroleum System of Qingshankou Formation was clarified. It was identified that at the end of Nenjiang Formation deposition, the source rocks of Qingshankou Formation entered the peak hydrocarbon-expulsion stage while the reservoirs had not yet undergone compaction, allowing conventional oil to accumulate first. From the end of Nenjiang Formation deposition to the end of Mingshui Formation deposition, source-reservoir systems evolved synergistically. The reservoirs were progressively tightened and trapped high-maturity oils, thus forming tight oil reservoirs. The key retention period for shale oil was from Nenjiang Formation deposition stage to the Early Paleogene. (3)The spatial distribution of the Whole Petroleum System of Qingshankou Formation in Qijia-Gulong sag was described at two hierarchical levels, i.e., the internal stratigraphic distribution and the overall system-wide distribution. In Qingshankou Formation, shale oil, tight oil, and conventional oil reservoirs develop successively from the basin center toward the margins, exhibiting an orderly spatial pattern. (4)The "six-map-and-one-table" characterization system was established for the first time, enabling a comprehensive depiction of the Whole Petroleum System across multiple dimensions, including geological element assemblages, geological evolutionary processes, temporal-spatial coupling of hydrocarbon accumulation, and spatial distribution characteristics. This study advances and refines the Whole Petroleum System theory and provides theoretical and technical support for hydrocarbon exploration in continental basins.

Key words: Whole Petroleum System, element, evolution, sequential distribution, "six-map-and-one-table", Qijia-Gulong sag, Qingshankou Formation