苏北盆地高邮凹陷古近系戴南组层序发育模式及控制因素研究

根据岩心、钻井、地震及分析化验等资料，对高邮凹陷的主力勘探层系———古近系戴南组进行了层序地层综合研究。 首先，根据层序边界的识别标志对层序进行划分，将戴南组划分为 3 个三级层序和 8 个四级层序，并建立了层序地层格架。 其次，建立了 2 种层序发育模式，一种为完整型湖泊层序发育模式，由低位体系域、湖侵体系域和高位体系域构成；另一种为不完整型湖泊层序发育模式，由低位体系域、湖侵体系域构成。 最后，通过分析层序发育的控制因素，认为构造沉降速率是控制三级层序结构的主要因素之一，气候变化引起的湖平面变化和沉积物供应速率是控制四级层序结构的主要因素。

Study on sequence models and controlling factors of Paleogene Dainan Formation in Gaoyou Sag,northern Jiangsu Basin

According to core, drilling, seismic data and laboratory analysis, this paper carried out a comprehensive study on sequence stratigraphy of Paleogene Dainan Formation in Gaoyou Sag. The sequences were divided into three third-order sequences and eight fourth-order sequences accorded to the identifying mark of sequence boundary, and the sequence strtigraphy framework was established. Two kinds of sequence models were established. One is a completed lacustrine sequence model, and it is composed of lowstand system tract, transgressive system tract and highstand system tract. Another is an uncompleted lacustrine sequence model, and it is composed of lowstand system tract and transgressive system tract. At last, the controlling factors to the sequence development were analyzed. It is considered that the tectonic subsidence is the main controlling factors for the third-order sequence structure, and that the lake level change caused by the climate and the rate of sediments supplying are the main controlling factors for the fourth-order sequence in this area.