Marr小波变换分频技术在隔夹层识别中的应用  

Application of Marr wavelet transform frequency division technology in intercalated stratum identification

作　　者：鞠颢 程超 苏畅 JU Hao;CHENG Chao;SU Chang(Shanghai Branch,CNOOC,Shanghai 200335)

机构地区：[1]中海石油(中国)有限公司上海分公司,上海200335

出　　处：《长江大学学报（自然科学版）》2022年第3期46-56,共11页Journal of Yangtze University(Natural Science Edition)

基　　金：国家科技重大专项“东海厚层非均质性大型气田有效开发关键技术”(2016ZX05027-004);中海石油(中国)有限公司综合科研项目“西湖凹陷中深层河流相储层表征及剩余油气挖潜”(YXKY-2019-SH-01);中海石油(中国)有限公司重大科技项目“东海上产560万吨关键技术研究”(CNOOC-KL 135ZDXM 39 SH03)。

摘　　要：油气藏隔夹层分布是影响流体渗透及油气藏采收率的关键因素,油气藏隔夹层认识对查明剩余油气分布、采取合理开发技术政策、提高油气采收率等十分重要。传统的油气藏隔夹层识别技术过度依赖井点数据,要得到可靠的隔夹层展布认识必须拥有足够多的井资料,对于井数较少的海上油气田来说难以使用传统方法开展精细隔夹层研究。Marr小波变换构造简单,比其他小波变换计算速度快,其低频和高频信号的准确性要远高于短时傅里叶变换,模拟雷克子波对地震记录进行分频,可有效提高分辨地质体的精度;其分频处理具有可逆性,分频后的信号相加能够恢复原始信号,且计算误差极小。为此,提出了一种基于Marr小波变换分频技术的隔夹层识别方法。首先通过选择合理的实钻岩石物理参数,在正演模型上实现Marr小波变换分频,验证其理论上的正确性;再在实际应用中充分利用地震频率域资料识别和追踪单井多期隔夹层在平面上的展布规律,得到了较为可靠的三维隔夹层识别成果,成功指导了海上某气田的开发实践。Distribution of intercalated strata in reservoirs is a key factor affecting fluid permeability and oil recovery.It is of great importance to identify intercalated strata in terms of understanding residual oil distribution,optimizing production strategies and enhancing oil recovery.The traditional reservoir interlayer identification techniques rely excessively on well point data and a big number of well data are necessary in order to obtain a reliable understanding of interlayer distribution.For offshore fields,however,due to limited number of wells,it is difficult to use traditional methods to carry out fine interlayer research.Marr wavelet transform is simple in construction,faster in calculation than other wavelet transforms,and its accuracy of low and high frequency signals is much higher than that of short-time Fourier transform,which can effectively improve the accuracy of geological body resolution by simulating the frequency division of seismic records by Ricker wavelet.Its frequency division processing is reversible,and the original signal can be restored by adding the signals after frequency division,and the calculation error is very small.Therefore,a method of interlayeridentification based on Marr wavelet transform frequency division technology was proposed.Firstly,by selectingreasonable physical parameters of real drilling rock,Marr wavelet transform frequency division was implemented on the forward model to verify its theoretical correctness.In the practical application,the seismic frequency domain data were made good use to identify and track the distribution law of multi-stage interlayer in the plane of single well,and relatively reliable three-dimensional interlayer identification results were obtained,which successfully guided the development of an offshore gas field.

关 键 词：Marr小波变换 分频技术 频谱分解 隔夹层 气田开发 

分 类 号：P631.44[天文地球—地质矿产勘探]