Converted-Wave Seismic Reflection as an Alternative Key to Unlock Near Surface Imaging

Near surface phenomenon, such as shallow soft soil and gas cloud, has been proven for years as one of the obstacle in geotechnical and petroleum industry. Present as the anomaly to its lithological surrounding, these phenomenon have a similar characteristic in which triggering an imaging quality degradation, especially captured in conventional seismic reflection. Conventional seismic reflection is widely applicable for a deep target imaging, but it’s not impossible to use for a shallow target purpose. Multicomponent seismic survey records conventional both PP-wave reflection and converted PS-wave reflection. Obtained from converted-wave seismic, the characteristic of S-Wave brings along its unique capability of only propagating in solid medium. Through synthetic model based on real velocity data, this research will unveil the ability of converted-wave seismic in assisting conventional seismic for imaging purpose. With the interest located in shallow depth, a different approach will be conducted to bring in the best feature of each seismic wave behavior. The result reveals a series of simple seismic attribute and post-stack seismic inversion just the right approach to handle the intermeshing characteristic of PP&PS seismic reflection. Reducing ambiguity of PP seismic, PS seismic provides a highly improved imaging even when it is a near surface phenomenon.