基于纵波频散谱的缝洞碳酸盐岩储层有效性评价

Effectiveness Evaluation of Fractured Vuggy Carbonate Reservoir Based on P-Wave Dispersion Spectrum

针对缝洞碳酸盐岩评价问题,采用物理实验手段对致密和缝洞发育的白云岩岩心样品在低频段进行不同频率下纵波速度变化情况的测量,分析缝洞发育程度有差异的岩心样品纵波速度随频率变化的响应规律。针对XMAC系列仪器有较宽频带响应范围的特点,形成了针对阵列声波数据的低频纵波频散分析处理方法,将岩心实验结果与阵列声波数据低频纵波频散分析处理结果相联合,通过谱域加权相似法处理得到的单点频散曲线,经统一刻度形成基于纵波频散谱的缝洞碳酸盐岩储层有效性评价方法。该方法在四川盆地缝洞型白云岩储层评价中取得良好效果,为缝洞碳酸盐岩储层有效性评价提供了思路和研究方向。

Aiming at the evaluation of fractured vuggy carbonate rocks,physical experiments were used to measure the variation of P-wave velocity at different frequencies of dense and fractured vuggy dolomite core samples at low frequencies,and the response law of P-wave velocity with frequency variation of core samples with different fracture vuggy development degrees was analyzed.In view of the wide frequency response range of XMAC series instruments,a low-frequency P-wave dispersion analysis and processing method for array acoustic data is developed.The coring experimental results are combined with the low-frequency P-wave dispersion analysis and processing results of array acoustic data,and the single point dispersion curve obtained by spectral domain weighted similarity method is uniformly calibrated to form a effective P-wave dispersion spectrum evaluation method of fracture vuggy carbonate reservoir.This method has achieved good results in the evaluation of fractured vuggy dolomite reservoirs in Sichuan Basin.This method provides ideas and research directions for the effectiveness evaluation of fractured vuggy carbonate reservoirs.