关键词: 高凸起斜坡带, 新近系, 油气成藏, 勘探实践, 济阳坳陷

Abstract:

Slope zone of the high salient in Jiyang depression occurs structurally as a monocline uplifting toward the high salient, and is often neglected because it is usually treated as a pathway for hydrocarbon migration toward the main body of the high salient. Being influenced by the basement palaeotopography with alternation of gullies and ridges and changes of Neogene sedimentary facies, five types of small but prolific secondary reservoirs tend to occur in the slope zone of the high salient, i. e. stratigraphic overlapped oil reservoir, reversed roof fault-block oil reservoir, small and low-amplitude secondary oil reservoir, small and low-amplitude buried hill drape oil reservoir and lithologic oil reservoir. Hydrocarbon migration pathways have relatively large influences on these reservoirs. Most of the reservoirs with unconformities as migration pathways are of relatively large, layered, stratigraphic overlapped oil reservoirs, characterized by zonal distribution with narrow oil-bearing zone. While reservoirs with inherited active boundary faults as migration pathways are characterized by long oil-bearing intervals, multiple oil-bearing series and complicated oil-water relationship. Suitable exploration methods and strategies should be taken for different types of reservoirs in the slope zone.

Key words: slope zone of high salient, Neogene, hydrocarbon reservoiring, exploration practice, Jiyang depression