3D seismic exploration in the Black Sea
Total and partners have realized two of the largest 3D seismic surveys in the Black Sea on Block Han Asparuh. The first survey was implemented in 2012-2013 by one of our partners, OMV, in the western part of the Block (this was the largest survey in the Black Sea at the time). The second survey has been successfully completed by Total between March and May 2020 in the eastern part of the block.
Two major seismic data acquisition campaigns to image entirely Han Asparuh Block underground in 3D
We have successfully acquired 7 740 km2 in 2012 and 5600 km2 in 2020 of 3D seismic data from Block Han Asparuh. The block has been now almost entirely covered with high-end seismic imaging technology. Drilling locations are optimally defined by combining the analysis of the 3D underground image with geological information coming from neighboring wells and regional geological knowledge. In 2012 our partner OMV managed the seismic operations. In 2020 Total organized and supervised the operations in a complex period at the start of the COVID-19 pandemic. One of the world largest seismic vessel (the OceanVega) has been used. Thanks to the dedication of the seismic contractor team (Shearwater), the campaign has been successful.
The first seismic campaign helped understanding the geology of the western part of the block and locate and drill safely the first three exploration wells that demonstrated the existence of a petroleum system.
The second campaign aims at imaging in 3D the underground of the eastern part of the block and at possibly define the location of future exploration wells.
Everyone is familiar with the use of echography to image babies. Seismic data acquisition is based on the same principle but on a much larger scale with the objective to image the underground.
A huge amount of data has been collected from the seismic studies on Han Asparuh: about 350000 Gbytes of data have been recorded in 2020 (this is equivalent of the size of a collection of about two hundred thousand 2 hours movie in digital format!).
In order to build a 3D image of the underground of the entire area with the recorded data, several months of high-end processing on High Performance super computers such as TotalEnergies' Pangea are necessary.
Best-in-class Environmental Protection
During the survey international industry guidelines including for minimizing acoustic disturbance to marine mammals were followed and measures were taken to observe and protect marine mammals.
Mitigation protocols have been developed and implemented to reduce the risk of adverse impacts on marine mammals including "soft-start" and "shut-down" rules based upon PAM (Passive Acoustic Monitoring) and visual monitoring of marine mammals and birds to monitor the exclusion zone (500 m) around the sound source and to delay or stop operations should any marine mammals be observed within a safety zone. The data received from marine mammals observation with recording forms and sighting photos was shared with the relevant Bulgarian institutions.
Energy diversification possibilities
Successful exploration could lead to future production of hydrocarbons in Bulgaria. This would definitely open new horizons for Bulgaria energy sourcing. Seismic acquisitions conducted on Block Han Asparuh are definitely a milestone in understanding the resource potential of the deep waters of the Black Sea.