Royal Dutch Shell told reporters in Sofia on Tuesday that it will launch an exploratory drilling operation next month in the Han Kubrat oil and gas field off the coast of Burgas in the Black Sea.
The 90-day exploration will commence off the Noble Globetrotter II ship on 1 April 1, about 80 kilometres from Burgas in south-east Bulgaria.
The drilling will use conventional methods and not hydraulic fracking of the rock surface, and it is estimated that the chances of finding commercially exploitable resources are one in five.
The period between the exploration phase and the beginning of the exploitation and the production of the crude oil from the potential oil field may take between six to ten years.
The exploitation phase will then continue for between 20 and 30 years after that,
Oil and gas fields with similar characteristics yield up to 75,000 barrels of crude oil per day.