Abstract: The deep coalbed methane (CBM) resources are abundant in Ordos Basin, and three difficulties in seismic technology are encountered in CBM exploration and development, including low signal-to-noise ratio of loess mountain data, thin thickness and rapid lateral changes of coal seams, and high requirements for sweet spot prediction accuracy. To realize the large-scale high-efficiency development of deep CBM, in recent years, significant advances have been made in the integrated technology of seismic acquisition, data processing and interpretation as well as seismic geology and engineering for deep target CBM reservoirs in the eastern margin of Ordos Basin. The application of "wide azimuth, broadband, and high-density" seismic acquisition technique and "high fidelity, high resolution" data processing technology in loess mountain area provides a high-quality data for seismic exploration of deep CBM. As a result, the main frequency of target layer for CBM seismic exploration can reach up to 40 Hz, and the frequency band can be broadened by more than 10 Hz, thus steadily improving the imaging accuracy. The fine structure interpretation and reservoir evaluation technologies have laid a solid foundation for the location of dual CBM sweet spots. The predicted thickness of coal seam is 5 m and the coincidence rate between the predicted and measured values of fractures can reach 79%. The application of seismic geology and engineering integrated technology has realized the effective extension of seismic exploration to geological development, increased the drilling encounter rate of coal seams to more than 97%, and the output of horizontal wells has reached 100 000 cubic meters, providing strong support for the efficient production of CBM in the study area.

Key words: deep coalbed methane, seismic exploration, dual sweet spots, integration of seismic geology and engineering, drilling encounter rate

摘要： 鄂尔多斯盆地深部煤层气资源丰富，对其进行勘探开发面临着黄土塬资料信噪比低、煤层薄且横向变化快、"甜点"预测精度要求高3方面地震勘探技术难题。为实现深部煤层气的规模效益开发，近年来针对鄂尔多斯盆地东缘深部煤层气目标的地震采集—处理—解释一体化技术和地震—地质—工程一体化技术有显著进步，黄土山地区"两宽一高"（宽频、宽方位、高密度）地震采集技术及"双高"（高保真、高分辨率）地震资料处理技术的应用为深部煤层气地震勘探构建了高品质的数据基础，使得地震勘探目的层的主频达到40 Hz，频带拓宽了10 Hz以上，成像精度稳步提高。精细构造解释及储层评价技术为落实煤层气"双甜点"奠定了坚实的基础，煤层预测厚度达到5 m，裂缝预测吻合率达到79%。地震—地质—工程一体化技术的应用实现了地震勘探向地质开发的有效延伸，鄂尔多斯盆地大宁—吉县区块煤层钻遇率提高到97%以上，水平井的产气量达10×10⁴m³/d，有力支撑了煤层气的高效建产。

关键词: 深部煤层气, 地震勘探, "双甜点", 地震—地质—工程一体化, 钻遇率