Multiple seismic attribute analyses for determination of bottom simulating reflector of gas hydrate seismic data in the Ulleung Basin of Korea

The bottom simulating reflector (BSR), the boundary between the gas hydrate and the free gas zone, is considered to be the most common evidence in seismic data analysis for gas hydrate exploration. Multiple seismic attribute analyses of reflectivity and acoustic impedance from the post-stack deconvolution and complex analysis of instantaneous attribute properties including the amplitude envelope, instantaneous frequency, phase, and first derivative of the amplitude of seismic data have been used to effectively confirm the existence of a BSR as the base of gas hydrate stability zone. In this paper, we consider individual seismic attribute analysis and integrate the results of those attributes to locate the position of the BSR. The outputs from conventional seismic data processing of the gas hydrate data set in the Ulleung Basin were used as inputs for multiple analyses. Applying multiple attribute analyses to the individual seismic traces showed that the identical anomalies found in two-way travel time (TWT) between 3.1 and 3.2 s from the results of complex analyses and l ₁ norm deconvolution indicated the location of the BSR.