沁水煤田中东部位于沁水块坳的东部,地形起伏剧烈,地表岩性变化较大,浅地表不均匀性对煤层气、页岩气的地震勘探有效探测带来较大的影响,选择有效的激发、接收参数成为采集阶段的主要难点. 文中提出采用微测井和折射相遇法相结合的方法,实现对浅表层结构的精细调查. 即根据微测井数据,确定合理激发层位,保证药柱在基岩或者致密粘土层中激发;通过对激发、接收条件进行系统的试验,得出了针对不同激发岩性选用不同井深、药量、组合的激发参数;通过对试验数据分析,选择多个低频检波器最佳组合,建立高覆盖次数观测系统. 采集成果证明,所选择的激发和接收参数较好地压制了面波、多次折射等干扰波,解决了山区、特别是黄土地区信噪比低的问题,为今后类似地区进行非常规天然气勘探开发提供了有益借鉴.%The middle-east area of the Qinshui coalfield is located in eastern Qinshui block depression, where terrain undulates obvi-ously and the surface lithology is changeful. The anisotropy of shallow surface causes more impact on the efficient detection of the coal-bed methane and shale gas in the seismic exploration. How to choose the excitation and receiving parameters becomes the main difficul-ty. In this paper, the methods of micro logging and refraction encounter were used to investigate the structures of shallow and surface. According to well logging data, the authors determined the reasonable excitation horizon so as to assure the exploration-grains explosion in the bedrock or dense clay layer; the excitation parameters of well depth, charge mass and well combination of different lithologies were obtained through the study of the systematic test of excitation and receiving condition;through the analysis of the test data,the au-thors chose the combination of low frequency detectors and built the recording geometry with multifold. Practices prove that the excita-tion and receiving parameters of this region can suppress the interference waves such as the surface wave and the multiple refraction wave and can resolve the problem of low signal-to-noise ratio in mountainous areas, especially in loess areas. The results obtained by the authors provide useful references for the exploration and development of unconventional natural gas in the future.
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