3D Black Sea - Batumi Seep

During the Meteor cruise M72/3b, a high-resolution 3D multichannel seismic dataset was recorded at the Batumi Seep Area, which is located at the Eastern Black at the continental slope offshore Georgia. The slope is characterized by a complex canyon-ridge system. The Batumi Seep is located on the Kobuleti Ridge in a water depth of around 850 m. Here, active seepage occurs within the gas hydrate stability zone.

The data comprises 72 individual lines with a spacing of 25 m. By using small bin sizes, a high resolution in all three dimensions was achieved. The implementation of a precise velocity analysis increased the data quality significantly. The processing preserves low frequencies to study attenuation and achieve a high penetration. Migration was performed in inline and crossline direction. 

As a result several small- and large-scale features facilitating and controlling the seepage in this area were identified. The 3D survey covers three seep sites, namely the Batumi Seep, the Kobuleti Seep and the Poti Seep. The seepage in all areas is related to vertical distinct and narrow zones of low amplitude which represent permeable pathways facilitating upward gas/fluid migration from greater depth. 

The top of free gas is represented by a series of discontinuous reflectors of high amplitude and reverse polarity. Deviations of the observed depth of the top of gas and the theoretical depth of the base of the gas hydrate stability zone indicate the local ascent of warm and/or highly saline fluids at the seep sites and the presence of impermeable sediments. 

Master Thesis

Marinkovic, Henning (2017) Processing and interpretation of a three-dimensional highresolution multichannel seismic dataset from the Batumi Seep Area, Eastern Black Sea. MSc Thesis.