Single Sensors Versus Hard-wire Arrays in Pre-stack Stereotomography

The surface waves are considered the main type of noise present on the land seismic reflection data. For decades, the hard-wired arrays are successfully used for their attenuation. Unfortunately, according to some modeling results, the hard-wired arrays can destroy the seismic signal (primary reflected waves). This is the case of the use of arrays in zones with rough topography where, locally, the reflections seen on the array responses are stretched and show very low amplitude; as a result, the signal-to-noise ratio of the responses is lower. And this is only one example of sources of amplitude variations which can decrease the signal-to-noise ratio of seismic records. The processing of the seismic data characterized by low signal-to-noise ratio can be difficult to perform; for example, the velocity analysis depends on the presence of clear reflections. A very efficient technique used for performing a velocity analysis is the pre-stack stereotomography, but we will show that its results are a function of the quality of input data. If we analyze array responses from an area with rough topography as input data, the responses based on the single-sensor recordings can be successfully used in the pre-stack stereotomography compared to those obtained using hard-wired arrays.