【摘要】 前第三系顶面不整合在冀中坳陷油气成藏和潜山形成过程中起重要作用.利用地震资料将冀中坳陷前第三系顶面不整合划分为断层-超覆不整合、削截-超覆不整合、断褶不整合、削截不整合和平行不整合等5种类型,其中断层-超覆不整合分布于陡坡带,削截-超覆不整合分布于缓坡带,断褶不整合多分布于中央隆起带,削截不整合多分布在凸起上,平行不整合则分布在生烃区.通过野外踏勘、岩心观察、录井与测井综合解释以及钻井泥浆漏失统计,将冀中坳陷前第三系顶面不整合纵向上划分为底砾岩、风化黏土层及风化淋滤带3层结构,其中风化淋滤带溶蚀孔、洞、缝十分发育,是油气运移和聚集的良好场所.目前已发现削截-超覆型油气藏、侵蚀潜山型油气藏和断褶不整合型油气藏等3类与不整合相关的油气藏.更多还原

【Abstract】 The unconformities on the top of Pre-Tertiary play an important role in the accumulation of hydrocarbon and the formation of buried hill in Jizhong Depression.By the analyses of seismic data,the unconformities on the top of Pre-Tertiary can be divided into five types:fault-overlap unconformity,truncation-overlap unconformity,fault-fold unconformity,truncation unconformity and parallel unconformity.The fault-overlap unconformities distribute in steep slope belt;the truncation-overlap unconformities distribute in gentle slope belt;the fault-fold unconformities distribute in central uplift belt;the truncation unconformities distribute in uplift region;the parallel unconformities distribute in hydrocarbon generation region.By field investigation,core observation,well-logging response and drilling data,the unconformities on the top of Pre-Tertiary are vertically divided into three parts:basal conglomerate,weathered clay layer and leached zone.There are massive solution pores,holes and fractures in the leached zone,which is a good place where hydrocarbon migrates and accumulates.Currently,it is discovered that there are three types of oil and gas reservoirs related to the unconformities,they are runcation-overlap unconformity reservoirs,corrosion buried-hill reservoirs and fault-fold unconformity reservoirs.更多还原