摘要
四川盆地碳酸盐岩储层埋藏深、缝洞发育、非均质性强,储层与上下围岩的波阻抗差异小,难以形成强的反射界面,其内幕表现为断续、弱能量的地震反射特征,致使储层的地震响应更加微弱。针对原始地震资料反射信号弱、频率衰减严重的特点,以信号保真去噪、弱反射信号的振幅、频率恢复和叠后处理技术为研究重点,开展了深层碳酸盐岩弱反射信号处理技术攻关研究。研究结果表明:①采用保真组合去噪技术较好地保护了二叠系储层弱反射信号;②采用地震处理获得的层速度,按照经验公式计算地层Q体数据并进行波动方程Q吸收补偿,对储层弱反射损失信号进行了较好的恢复;③偏移后采用优势道集叠加,并对新叠加数据体进行子波整形保真拓频,凸显了二叠系储层的地震响应。通过在射洪、西充等地区二叠系茅口组储层预测中的应用,获得了89%的储层预测成功率。
With well-developed fractures and vugs,most carbonate reservoirs in Sichuan Basin are characterized by deep burial depth and high heterogeneity.They are slightly different in wave impedance from overlying and underlying surrounding rocks,making it impossible to generate strong reflector exhibiting intermittent and low-energy reflected properties.As a result,their seismic response is more feeble.So,considering original seismic data with weak reflected signals and severe frequency attenuation,four technologies were studied for weak reflected-signal processing in deep carbonate,including fidelity denoising of signals as well as amplitude and frequency restoration and post-stack processing of weak signals.Results show that(i)feeble reflected signals in Permian reservoirs can be well protected by using the fidelity denoising;(ii)adopting formation velocity gained from seismic processing,these weak re-flected loss signals of reservoirs are recovered effectively through the Q data calculated by the empirical formula and the Q absorption compensation of wave equation;and(iii)wavelet shaping and fidelity frequency expansion can be conducted for newly stacking data-base via dominant-gather stacking after migration,which gives prominence to the seismic response of Permian reservoirs.The success rate of reservoir prediction up to 89%has been achieved after the application of these processing technologies to the Permian Maokou Formation in Shehong and Xichong areas.
作者
何宗强
何青林
韩嵩
曾鸣
刘晓兵
戴隽成
屠志慧
孔令霞
HE Zongqiang;HE Qinglin;HAN Song;ZENG Ming;LIU Xiaobing;DAI Juncheng;TU Zhihui;KONG Lingxia(Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China)
出处
《天然气勘探与开发》
2023年第4期99-106,共8页
Natural Gas Exploration and Development
关键词
弱反射信号处理
保真去噪
波动方程
Q吸收补偿
优势道集叠加
子波提取
子波整形
储层预测
Weak reflected-signal processing
Fidelity denoising
Wave equation
Q absorption compensation
Dominant-gather stack-ing
Wavelet extraction
Wavelet shaping
Reservoir prediction
