牛庄洼陷西部沙三中压力与油藏分布关系研究

Study on the Correlation between Pressure and Reservoir Distribution of the Es3～z Member in the West of Niuzhuang Subsag

牛庄洼陷是胜利油田东营凹陷的一个重要生油洼陷,沙三中亚段为主要勘探目的层,其中浊积砂体构成了该区主要储集体。本研究利用区内47口井的声波测井时差值,通过泥岩等效深度法计算出了沙三中亚段的5个砂层组的地层压力系数,对牛庄洼陷西部沙三中压力与油藏分布关系进行了研究,得出沙三中超压现象明显,压力为油气运移提供了重要的源动力,目前已发现的油藏大致沿高压、超高压带分布。结合地震反演资料,并叠合砂体埋藏深度、断层及沉积相等诸多因素,预测出了三个有利砂体。

The Niuzhuang Subsag is one of the most important oil generation subsags and the middle Section in Member 3 of Shahejie Formation （abbreviated to the Es3-z Member） is main exploration strata in Dongying Sag of Shengli Oilfield, in which the turbidite sandbodies form the main reservoir bodies in this area. The strata pressure coefficient of 5 sandbodies are worked out by means of mudstone equivalent depth with the acoustie log time-difference of 47 well drillings. The correlation between pressure and reservoir distribution of the Es3 - z Member in the west of Niuzhuang Subsag is studied. The study has indicated that overpressure phenomenon is obvious and this overpressure provides the important original power for the oil-gas migration, and found that the reservoirs distribute generally along the high pressure and extra-high pressure zones. The three favorable sandbodies are forecasted by combining with the seismie inversion data and integrating with such factors as the buried depth of sandbodies, faults, sedimentary facies, and so on.