[目的]随着深部资源勘探开发的重要性不断提高，对高精度地震勘探提出了新要求。针对具有强各向异性的含煤地层，传统基于各向同性的资料处理方法不再适用。[方法]提出一种基于水平横向各向同性介质(Transverse Isotropy Medium with Vertical Symmetry Axis，VTI)和方位各向异性介质(Transverse Isotropy with Horizontal Axis of Symmetry，HTI)联合处理的地震数据处理方法。首先，针对含煤地层沉积特征，分析VTI介质特点，采用高阶动校正处理，可以有效消除各向异性在大偏移距数据中引起的同相轴弯曲，保证共反射点远近道能达到同相，提高数据叠加成像质量。其次，针对构造裂隙发育特征，立足于HTI介质的方位各向异性分析，采用OVT域处理方法，通过建立方位各向异性参数场去除不同方位角差异对数据的影响。联合应用上述 2种处理方法，通过制定合理的处理流程，优选关键参数，搭建一套实用的、适合目标地层的各向异性处理校正方法，解决含煤地层在复杂条件下的速度分析、叠加等问题，从而提高煤系地震数据的分辨率和解释精度。[结果和结论]实际应用结果表明，新方法获得的地震数据主频更高、频带更宽，在小构造特征识别和古地理环境刻画方面更具优势，为精细地质解释提供了有力支撑。同时也强调了对含煤地层进行各向异性处理的必要性，推动各向异性处理技术的在宽方位地震勘探中的应用。
A high-resolution method for processing coal measures seismic data based on anisotropic medium theories and its application
[Objective]The increasing importance of the exploration and exploitation of deep resources poses new re-quirements for high-precision seismic exploration.Given that conventional isotropy-based data processing methods are no longer applicable to the coal-bearing strata with strong anisotropy.[Methods]This study proposed a method for pro-cessing seismic data based on theories of both transverse isotropy medium with a vertical symmetry axis(VTI)media and transverse isotropy with a horizontal axis of symmetry(HTI)media.First,to characterize the depositional character-istics of coal-bearing strata,this study analyzed the features of VTI media,revealing that high-order dynamic correction can effectively eliminate anisotropy-induced event bending in large-offset seismic data,thus ensuring that the common reflection points in both far and near channels can be in-phase and improving the data stacking and imaging quality.Second,targeting the characteristics of tectonic fissures,this study relied on the azimuthal anisotropy analysis of HTI media.Specifically,using Offset-Vector Tiles(OVT)domain processing,the influence of varying azimuthal differences on data was removed by establishing the parameter fields of azimuthal anisotropy.Using both methods,this study de-veloped a practical processing and correction method suitable for target strata with anisotropy by establishing a rational process and choosing optimal key parameters.This method can achieve effective velocity analysis and data stacking of coal-bearing strata under complex conditions,thus improving the resolution and interpretation accuracy of coal meas-ures seismic data.[Results and Conclusions]The application results indicate that the new method can obtain seismic data with higher dominant frequency and a wider frequency band and is more advantageous in identifying the features of small structures and characterizing paleogeographic environments,thereby providing strong support for the fine-scale geological interpretation.This study highlighted the necessity of the processing of anisotropy for coal-bearing strata,po-tentially promoting the applications of anisotropy processing techniques in wide-azimuth seismic explorations.
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