Low-Amplitude Structures and Oil-Gas Enrichment on the Yishaan Slope, Ordos Basin
详细信息
- 责任者：Wang Jianmin (School of Earth Science and Engineering ; Xi’an Petroleum University ; Xi’an 710065 ; China) ; Wang Jiayuan
- 刊名：Petroleum Exploration and Development
- 出版年：2013
- 卷期：40(1)
- 关键词：油气聚集 ; oil and gas accumulation ; 鄂尔多斯盆地 ; Ordos Basin
- 页码：p.49-57
- 图表：illus., 27 refs.
- 分类号：1003
- issnNo：ISSN1000-0747
- isbnNo：CN11-2360/TE
摘要
Considering the geological and tectonic characteristics and based on drilling data and production test results,a drawing method with a dense well pattern and large scale was used to analyze the low-amplitude structures and oil-gas enrichment in the Yishaan slope,Ordos Basin.Low-amplitude structures are developed regionally and intensively,extended directionally in array folding,and evolved inheritedly.Based on geometry,coverage and genesis,the structures are divided primarily.With tectonic stress as the driving factor,the low-amplitude structures contain basically nose-like units,in nearly E-W trend.The fluctuating attitude of strata at the break affects the driving force,speed and direction of oil-gas migration along the updip of the slope,making oil/gas/water differ in sections and oil/gas dissipate or cluster locally,so that the alternating oil-gas areas and the oil-water areas with more water are formed.A series of composite traps(lithologic-structural,structural-lithologic or stratigraphical-structural) are defined by combination of the endpoint connecting line of hinge zone in low amplitude tectonic slope break with the lithology or property pinch-out line of sedimentary facies belt side parts,or with local strata pinch-out line.In such traps,the hydrocarbons are accumulated.The advantageous configuration of low-amplitude structures and large sedimentary systems as well as favorable facies controls the oil and gas distribution in Mesozoic - Paleozoic formations in the Yishaan slope.