陇东地区长7致密油储层下限值的确定

Determination of lower limits for Chang 7 tight- oil reservoir in Longdong area

陇东地区长7致密油储层下限尚不明确,需建立其下限标准。利用毛管压力、岩心分析、油—水相渗及常规测井资料研究陇东地区长7致密油储层下限。采用优化后的平均毛管压力曲线确定了致密油层最小流动孔喉半径为0.054μm,孔隙度下限为5%,渗透率下限为0.03×10-3μm2;采用密闭取心刻度法与油—水相渗法确定了含油饱和度下限为58%,并通过实际生产验证了该下限的准确性,该下限的确定为陇东地区长7致密油储层测井解释提供了标准,为长庆油田的增储上产奠定了基础。

At present,the lower limits of Chang 7 tight -oil reservoirs in Longdong area need to be determined because their values are unclear.The lower limits were studied by capillary pressure,core analysis,oil -water relative permeability and conventional log data.Based on the optimized average capillary pressure curves,the minimum of flow pore throat radius is 0.054 μm,the lower limit of porosity is 5%,and the lower limit of permeability is 0.03 ×10 ^-3 μm^2 .By the sealing co-ring calibration and the oil -water relative permeability method,the lower limit of oil saturation is 58%,which has been verified by practical production.The lower limits provide a standard for logging interpretation of Chang 7 tight -oil reser-voirs in Longdong area and lay the foundation for increasing reserves and production of Changqing Oilfield.