Abstract:Data acquired by coiled geophones lacks components of which the frequency is lower than the natural frequency. These low-frequency components are very useful in many fields, such as FWI, velocity analysis, deep target imaging, etc. Low-frequency attenuation similar to physical filtering process can be described as a mathematical transfer function. Since geophone specifications(natural frequency, damp, sensitivity, etc) are known, its transfer function can be obtained. Theoretically, low-frequency attenuation can be compensated by geophone deconvolution. Tolerances of geophone specifications and noises other than geophone mechanical vibration system output are two factors which affect the compensation. According to our simulation, for widely used geophones(20DX), these two factors have very little effect on geophone deconvolution with seismic survey background(multi-coverage, strong noise, poor coupling), and the deconvolution can be accomplished with nominal value of geophone specifications. Thus with this "geophone deconvolution", low-frequency components lost at geophones during the acquisition can be recovered as digital sensors acquire. Seismic data previously collected by geophones can be enhanced with low-frequency components with the proposed approach.
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