Distribution of free gas and image structures beneath Sevastopol mud volcano, Black Sea, from a 3D study of a high resolution wide-angle seismic dataset

Combined geophysical, geological, and geochemical analyses were conducted to investigate gas-hydrate occurrence in the Sorokin Trough, Black Sea. This study concentrates on a 3D high resolution seismic grid recorded with 13 ocean bottom stations on Sevastopol mud volcano. The 3D nature of the experiment results from the geometry of densely spaced profiles as well as the cubical configuration of the densely spaced receivers on the seafloor (~300 m station spacing). Correlation of a 3D mirror image of the seismic records in addition with 2D velocity-depth inversions of several seismic profiles gives a quasi 3D image of the subsurface. The Kirchhoff mirror image time migration reveals the reflective structure of the sub-seafloor beneath the ocean bottom stations. The traveltime inversion reveals the seismic velocities along the profiles.