Sedimentary And Tectonic Evolution Of Nanpu Depression In Paleogene

Gaoliu area is located in the northern part of Nanpu depression, it is controlledby the Xinanzhuang fault in the west, and close to the Xinanzhuang uplift andLaowangzhuang uplift. In the east, it is controlled by the Baigezhuang fault, and closeto the Baigezhuang uplift and Matouying uplift. The Shahejie formation is the mainproduction reservoir of Nanpu depression. It can be divided into eight third-ordersequences.Based on the sedimentology, sequence stratigraphy and petroleum geology,analyzing the core data, logging data and seismic data, we made the study of theevolution of the sedimentary systems and tectonics in Nanpu depression, anddiscussed the accommodation transformation system in Nanpu depression.There are four types of sedimentary systems in Nanpu depression. They are thefan delta, braided river delta, the turbidite and the lake system. We identified thelocation of the source area of the Shahejie formation by analyzing the seismic dataand the activity of the fault. The maps of the distribution of sedimentary systems inShahejie formation are reconstructed by means of analyzing the seismic data, the welllogging data and the well core observation. In the Es3period, the Xinanzhuang faultrifted strongly, the fan delta develops mainly in the west part of the area. In the Es2and Es1period, the Baigezhuang fault rifted greatly, the western part of the areamainly develops the braided river delta and the east part of the area mainly developsthe fan delta system. The turbidite system mainly develops in the middle part of thestudy area.Combined the seismic data, the well core observation sequences and thestratigraphy thickness, we analyzed the change of the accommodation system inNanpu depression. In the Es3period, the Xinanzhuang fault rifted strongly, the depthof water is much deeper in the west and the thickness of the stratigraphy is muchthicker. In the Es2and Es1period, the Baigezhuang fault rifted greatly, the depocenteris located at the eastern part of the area. Finally, we discussed the relationshipbetween the accommodation transformation systems and the oil and gas reservoirs. Inthe accommodation increasing belt, it manly develops the cap rock and the sourcerock. In the accommodation decreasing belt, it mainly develops the reservoir rock.The activity of the fault can not only provides the channel of oil transportation, butalso form the structural reservoir.