地层抬升过程中的砂体回弹作用及其油气成藏效应

Relationship between Pore Variation of Reservoir and Rebounding of Sandstone during Uplift and Its Application to the Daqing Oilfield

地层抬升是盆地构造运动的主要表现形式之一 ,以往多强调其对油气藏的破坏作用 ,而忽略了其对油气成藏贡献的研究 .通过对不同粒级砂体在不同温度、压力条件下回弹量实验模拟 ,建立了其在地层抬升过程中不同地质条件下砂体回弹量模板 ;以大庆长垣为典型解剖实例 ,结合地层埋藏史、油气生排烃史研究 ,进而建立地层抬升造成的减压增容效应与油气成藏的定量关系模型 ,定量评估出大庆长垣地层抬升造成的砂体回弹效应对油气成藏贡献是 13.4 3%～ 4 0 .4 6 % .对油气成藏机理进行了新的探讨 ,可为油气资源分布预测研究提供更科学的依据 .

Uplift is one of the major patterns of tectonic movement in sedimentary basin. Its contribution to reservoir is neglected before, but the damage function is emphasized. Based on the rebounding simulation of sandstone by using different grain level sandstones under conditions of different temperatures and pressures, the quantitatively rebounding chart of sandstone in different geological conditions during uplift is established. Taking the Daqing placanticline as a typical example, the quantitative relationship between sandstone rebounding and reservoir formation was established based on integrated analysis of buried history, hydrocarbon generation and expulsion history. The contribution ratio due to rebounding of sandstone during uplift is 13.43% - 40.46% in the Daqing placanticline. The new method provided in this paper can offer more scientific basis for forecasting hydrocarbon distribution.