Wintershall ends activities in Mauretania
Wintershall, Germany’s largest internationally active crude oil and natural gas producer, has given back its two onshore licenses Ta5 and Ta6 for the Taoudeni Basin in Mauretania to the energy ministry of the North African country. Wintershall has been active in both blocks in the border region between Mali and Algeria since 2006. Although it was possible to prove the existence of hydrocarbons in the hottest and driest part of the Sahara in the studies conducted, the evaluation of the results of the exploration activities indicates that commercial production is not possible.
Wintershall began its exploration activities in the country with 3.2 million inhabitants at the beginning of 2007 with geological mapping and the drilling of test wells up to 250 meters deep. There were no detailed geological maps for the concession area; the experts had to draw these up first for the 68,700-square-meter area to prepare the search for hydrocarbons. The blocks were also investigated with an aerogeophysical survey by six airplanes. This technique investigates anomalies in the magnetic and gravitational field. The deviations allow initial conclusions on changes in density and the structures underground to be drawn. They also give the geologists information on whether the conditions for oil and gas deposits exist.
Once the modeling and evaluation of the aerogeophysical measurements were completed, in 2010 1,540 kilometers of 2D seismic acquisition was conducted on the structures detected. It took eight months to carry out the seismic surveys and required the presence of about 350 people in the field, 200 people to conduct the seismic surveys. Following the data processing and interpretation of the seismic surveys, it was possible to confirm the structural indications. However, the risk of discovering hydrocarbons that cannot be commercially recovered was considered too high to enter the next phase of exploration.