密闭取心井岩心油水饱和度校正方法研究

OIL AND WATER SATURATED CORRECTION OF THE SAMPLES FROM SEALED CORING WELLS

通过分析影响密闭取心井油水饱和度损失的相关因素,认为饱和度损失主要受降压脱气和岩石孔隙体积改变两个因素的影响。假设两个因素依次发生,推导出的油水饱和度损失校正关系式直观地表明:对油田某区块的储油层,其体积变化系数为一常数;其次已水洗或者油水同层的密闭样品其油水饱和度损失同时受降压脱气和岩石孔隙体积改变的影响,未水洗的密闭样品只受岩石孔隙体积改变的影响;最后岩石孔隙体积值改变由岩石自身的孔隙结构决定。

Through analyzing the correlative factors influencing oil and water saturation loss in sealed coring wells,it is thought that the loss is affected by two factors which are decompression degasification and variation of rock pore volume.Supposing two factors occur sequentially,the formula for oil and water saturation loss correction indicates that the coefficient of volume variation is a constant to the particular oilfield;secondly the oil and water saturation loss of washed samples or in oil and water zones is affected by both decompression degasification and pore volume but the unwashed sample is only affected by pore volume;thirdly pore volume is determined by its pore structure.