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应用层序地层学的基本概念和研究方法重新解释了冀中坳陷的下第三系地层。四个层序可从地震剖面和钻井资料中解释出来，每一层序可进一步划分成三个体系域：低水位期、水进期和高水位期。体系域的沉积或岩相的分布明显受湖水升降及构造沉降的双重作用控制，每一层序构成了水进到水退的沉积旋回。从现有的资料分析，冀中坳陷的水进期体系域可能与“海泛”或“海侵”有关，发育有较厚的暗色泥、页岩夹碳酸盐岩（包括生物碎屑灰岩）的沉积，并伴有大量的与“咸水”环境有关的微古生物，这些微古生物是形成油气的主要物质基础。而位于水进期之下的低水位期的盆底扇、斜坡扇、斜坡河道砂、水进三角洲和位于水进期之上的高水位期的水退三角洲、扇三角洲砂体是有利的储集层系。圈闭类型明显受砂体的成因类型控制。
Applying the basic concepts and research methods of sequence stratigraphy to redefine the Lower Tertiary strata in Jizhong depression. Four sequences can be interpreted from seismic profiles and drilling data. Each sequence can be further divided into three system domains: low water period, water period and high water period. The sedimentary or lithofacies distribution of the system tract is obviously controlled by the double action of the elevation of the lake and the tectonic subsidence. Each sequence constitutes the sedimentary cycle of water-water retreat. Based on the available data, the water system evolution of the Jizhong Depression may be related to “sea-pan” or “transgression”. Thicker dark muds are developed, and shale-capped carbonate rocks (including biological debris Limestone), accompanied by a large number of micro-paleontology related to the “saltwater” environment, these micro-paleontology is the main material basis for the formation of oil and gas. Basin subfacies, ramp fans, ramp channel sands, water deltas, and waterflood deltas located in the low water level beneath the water-dip period are favorable reservoirs Set system. The trap type is clearly controlled by the type of formation of the sand body.