地震低频提取技术在含油储层检测中的应用

储层含油气后会在地震资料的频谱上出现较为明显的衰减现象,利用这一特征可以进行油气检测。过去更多的计算方法是在高频段计算衰减梯度,并取得了较好的实用效果。随着高精度地震技术的进步,地震资料频带得到拓宽,低频信息也更丰富,提取地震低频信号具有重要的理论和实际意义。在地震低频信号段,研究发展了基于经验模态分解低频能量变化率的高精度的低频信号提取方法,使用该提取方法测试了正演模型,以及对研究区储层岩性油气藏进行了测试,效果与钻井吻合。研究结果表明,研究发展的低频信号提取方法进一步提高了油气检测能力。

Application of seismic low frequency to detect oil-bearing reservoir

The theoretical research shows that the reservoir,containing oil and gas,will have obvious attenuation in the spectrum of seismic data,and the oil and gas can be detected by using this feature.In the past,more calculation methods were used to compute the attenuation gradient in the high frequency band,and good practical results were obtained.In recent years,some researchers have proposed that seismic attenuation can be well characterized by seismic low-frequency signals.In the seismic low frequency signal segment,a high-precision low frequency signal extraction method based on the low frequency energy conversion rate of empirical mode decomposition is developed in this paper.The forward model is tested by this extraction method,and the lithologic reservoir in the study area is tested,and the results are consistent with drilling.The results show that the low frequency signal extraction method developed in this paper further improves the oil and gas detection capability.An energy conversion extraction method based on seismic low- frequency signal is developed.