宽频宽方位处理技术在淮北矿区全数字高密度地震勘探中的应用

Application of broadband and wide azimuth processing technology in full digital high density seismic exploration in Huaibei mining area

与常规三维地震勘探相比,全数字高密度地震勘探采用高横纵比、宽方位观测系统,使用单点数字检波器接收。宽方位地震勘探有利于高陡构造和复杂断块成像,但存在各向异性问题,而单点数字检波器地震信号频带宽、保幅性好、噪声强。为了充分发挥全数字高密度地震资料优势,克服其缺点,必须将宽频、宽方位处理技术运用到煤炭高密度三维地震数据处理中,以提升数据处理效果。以淮北矿区全数字高密度地震资料为基础,针对淮北矿区地质构造复杂特点,以叠前保幅去噪、振幅补偿、OVT处理技术以及全方位角偏移成像技术为重点,开展了煤炭全数字高密度地震资料的宽频、宽方位处理技术研究。结果表明:保幅去噪在几乎不损伤有效信号的前提下实现了对噪声的有效压制,振幅补偿恢复了地震信号高低频能量的损失,宽方位处理不仅消除了各向异性影响,改善了成像效果,还获得了丰富的叠前数据。宽频宽方位处理技术是全数字高密度地震资料处理的必要手段,其处理成果比常规处理成果频带更宽,对复杂构造成像更好,分辨率更高,能够实现煤田复杂地质条件地震资料精细成像。

Compared with conventional 3D seismic exploration,full-digital high density seismic exploration adopts high horizontal and vertical ratio,wide azimuth observation system and single-point digital detectors.Wide azimuth seismic exploration is beneficial to high and steep structure and complex fault block imaging,but there are anisotropy problems,while single-point digital geophone seismic signal has wide frequency band,good amplitude preservation and strong noise.In order to give full play to the advantages of the full digital high-density seismic data and overcome its disadvantages,broadband and wide azimuth processing technology must be applied to high density 3D seismic data processing in coal mining districts to improve the data processing effect.Based on the full digital high density seismic data of Huaibei mining area,this paper studies the broadband and wide-azimuth processing technology of the full digital high-density seismic data of coal mining districts,focusing on pre-stack amplitude preservation denoising,amplitude compensation,OVT processing technology and omni-directional angular migration imaging technology according to the complex geological structure characteristics of Huaibei mining area.The actual digital high density seismic data processing in Huaibei mining area shows that the image denoising in almost no damage under the premise of effective signals to realize the effective suppression of noise,restore the seismic amplitude compensation signal of high frequency energy loss,wide azimuth processing not only eliminates the anisotropy effect to improve the imaging effect,but also obtains rich pre stack data.Broadband azimuth processing technology is a necessary means for processing full digital high density seismic data.Its processing results are wider in frequency band than conventional processing results,better in imaging complex structures,higher in resolution,and able to achieve fine imaging of seismic data of complex geological conditions in coal mining districts.