摘要
辽河坳陷西部凹陷是中国东部油气资源丰度最高的地质单元之一,目前已产出大量原油,但天然气勘探研究相对薄弱。为此,根据地质条件及其变化关系分析,并侧重油气分布地质规律认识,将该坳陷西部凹陷划分为各自特征明显的4个油气成藏体系,分别是北部陡坡带、西部斜坡带、中部断背斜带和南部陡坡带成藏体系。各成藏体系的形成演化及含油气地质特点与西部凹陷的沉降—沉积中心由北向南、由西向东的迁移特点密切相关,有机质的生烃能力、油气的富集程度以及天然气的聚集丰度均受制于这一地质过程。作为多因素地质作用的结果,油气分布具有顺层、近源、受层系控制的成藏及分布模式,天然气分布主要出现在各成藏体系中靠近洼陷中心的地方,环绕鸳鸯沟、清水、盘山等南部洼陷,形成了天然气分布的环圈状特点,沉降—沉积中心的迁移和成藏体系的展布控制了该区天然气的空间分布。
Western depression of Liaohe subbasin is the geologic unit with highest abundance of petroleum resources in East China. It has produced large amount of oil so far, but is poorly explored in respect of natural gas. Based on the geologic conditions and their variations as well as distribution patterns of oil and gas, 4 petroleum systems with distinctly different characteristics are recognized in the Western depression of Liaohe subbasin, including the northern steep slope zone, western slope zone, central faulted anticlinal zone, and southern steep slope zone. Their formation, evolution and oil-and gas-bearing features are closely related with the migration of subsidence-depocenter from north to south and from west to east in the Western depression. This geologic process has controlled the hydrocarbon-generating potentials of source rocks and the abundance of oil and gas. The oil and gas reservoirs are characterized by bedding distribution, near source and control of layer system, while the natural gas reservoirs are mainly distributed near the center of structural low in each petroleum system. The gas reservoirs occur in circles around some structural lows in the southern part of the depression, such as Yuanyanggou, Qingshui, and Panshan. The migration of subsidence-depocenter and distribution of petroleum systems control the spatial distribution of gas in the study area.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2007年第5期39-43,共5页
Natural Gas Industry
基金
国家自然科学基金项目(编号:40472073)研究成果
关键词
辽河坳陷
西部凹陷
天然气
成藏体系
气藏形成
分布
Liaohe subbasin, western depression, natural gas, petroleum system, gas reservoiring, distribution
