中文摘要：

利用珠江口盆地深水区ODP1148站位的测井及岩心数据计算了现今的孔隙度及超压状态,通过求解水动力方程模拟了30 Ma以来孔隙度和超压场等的演化,探讨超压发育特征、演化规律及控制因素。模拟计算表明,研究区100m以浅的更新世地层为正常压力,深部产生超压。在约460m深度处孔隙度和超压增大,有效应力减小,对应滑塌层段的出现。早期沉积单元的超压演化特征与现今场并不完全相符,28.5~23.8 Ma期间超压突降,应为南海北部陆坡构造侵蚀事件的响应。沉积速率是控制珠江口盆地深水区超压演化的主要因素。本研究对超压含油气盆地的勘探与开发具有理论和实际意义。

英文摘要：

The present porosity and overpressure in the deep-water area of the Pearl River Mouth Basin（PRMB）have been calculated with the logging and core data of site 1148,ODP184,on the northern slope of the South China Sea,and the evolution of porosity and overpressure in the 30 Ma is simulated with the hydrodynamic model,which has been applied to investigate the characteristics,evolution and controlling factors of the overpressure.The study shows that the Pleistocene shallower than 100 m display normal formation pressure,and overpressure only occurs in the deeper strata.Porosity and pressure increase as effective stress decreases at about 460 mdepth,corresponding to the presence of the slumped unit.The evolution of the early-deposited sediments did not fully agree with the present field.The overpressure during28.5to 23.8Ma decreased sharply,which could be the response to the erosion event during this period on the northern slope of the South China Sea.Deposition rate is the dominating factor to the evolution of formation pressure in the deep-water area of PRMB.This study would be of theoretical and practical importance to the hydrocarbon-bearing basin with overpressure.