低信噪比地区地震采集激发技术探讨

由于受地表、近地表、地下复杂条件的影响,低信噪比地区干扰波发育,地震资料品质差。该类地区地震资料信噪比的提高和改善面临着诸多技术难题。地震激发技术是提高低信噪比地区地震资料信噪比的一项关键技术。为此,对地震激发技术进行了理论与实际相结合的探讨与分析。首先,通过多种方法综合的表层结构调查弄清复杂地表的表层结构,以帮助选取合适的激发岩性和激发参数；其次,利用基于地形与表层结构的动态设计技术设计井深；再次,依据地震波的能量、频率和信噪比的好坏优选激发药量；然后,利用基于能量和观测属性的激发点位选择方法选择激发点位；最后,采用组合激发和闷井技术提高激发效果。上述地震激发技术和配套工艺的应用,有助于提高低信噪比地区的地震资料品质。

Due to the complicated surface,near surface and subsurface conditions,interference wave is developed in low SNR area and seismic data quality is bad.The improvement of the SNR in this kind of area is faced with many technical difficulties.Seismic excitation technique is a key technique to improve the SNR in the area with low SNR seismic data.Therefore,we discuss and analyze the combination of the theory and application of seismic excitation technique.Firstly,surface structure investigation by integrating many methods is carried out to identify the surface structure of the area with complex surface conditions to help selecting probable shooting lithology and parameters.Secondly,dynamic design technique based on topography and surface structure is utilized to design well depth.Thirdly,explosive quantity is optimized by energy,frequency and SNR of seismic wave.Fourthly,shooting points are selected based on energy and geophone attributes.Finally,array excitation and stuffy well technique are applied to improve the shooting result.The above application is beneficial to improve the data quality in the area with low SNR.