【摘要】 黄骅坳陷埕北断坡处于歧口凹陷向埕宁隆起过渡的斜坡带上,发育多期不整合,这些不整合对该区的油气成藏具有重要作用。利用地震资料分析结果,将不整合划分为5种类型:褶皱不整合、断褶不整合、削截不整合、超覆不整合和平行不整合。其中平行不整合分布在凹陷区,褶皱不整合分布在基底,断褶不整合分布在大断裂下降盘,削截不整合分布在大断裂上升盘,而超覆不整合多分布在隆起斜坡区。利用测井资料分析结果,在纵向上将不整合划分为3层结构:不整合面之上岩石、不整合面之下的风化黏土层及半风化岩石。由于每层结构的岩性与厚度不同,可形成4种岩性配置模式。不整合构成了埕北断坡油气侧向运移的重要通道,同时在不整合面之上可形成超覆不整合油气藏,在不整合面之下依靠风化黏土层遮挡可形成削截不整合与褶皱不整合油气藏。勘探结果证实,研究区众多油气显示或油气藏均位于不整合面上、下50,m范围内。开展不整合与油气成藏关系研究,将有助于拓宽黄骅坳陷隐蔽油气藏的勘探空间,对中国东部油气资源挖潜具有重要的理论意义与实践意义。更多还原

【Abstract】 The Chengbei fault slope of the Huanghua Depression lies in the slope belt between the Qikou Sag and the Chengning Uplift,and it is characterized by the development of many unconformities. These unconformities are very important for hydrocarbon accumulation in this area. By analyses of seismic data,the unconformity can be divided into 5 types: folding unconformity present in the basement,faulting-folding unconformity present in the downthrown block of the large rift,truncating unconformity present in the upthrown block,onlaping unconformity present in the slope area of the uplift and parallel unconformity present in the sagging area. According to the log data analysis,the unconformities are divided into three parts vertically:rocks deposited above the unconformity interfaces,weathered clay layer and semi-weathered rocks below the unconformity interfaces. Because of the differences in thickness and lithology,the vertical profiles of unconformities include four patterns of lithology configuration. The unconformities in the Chengbei fault slope are not only the important pathways for lateral oil and gas migration,but also the favorable places for petroleum accumulation. Onlaping unconformity petroleum accumulations can be formed above the unconformity interfaces,and truncating and folding unconformity petroleum accumulations can be formed below the unconformity interfaces due to the presence of the weathered clay layer. The exploration has proved that there exist numerous oil/gas shows and petroleum accumulations in the 50 m ranges both above and below the unconformity interfaces. The studies of relationships between unconformity and petroleum accumulation will broaden the exploration area of subtle reservoirs in the Huanghua Depression and have important academic and practical significance for the further exploration in the basins in eastern China.更多还原