The companies plan to acquire about 2600km of 2D vibroseis data in the Dharoor Valley.

In the Nogal Basin, Africa Oil has acquired more than 4000km of 2D data that was recorded in the late 1980s.

Africa Oil holds an 80% interest in the Nogal and Dharoor blocks, and Range holds the remaining 20%.

The partners plan to drill two wells in each of their two Puntland, Somalia concessions, while drilling in the Nogal region was due to begin in April but was interrupted by "civil unrest".

However, Range and Africa Oil have put on a brave face. While Somalia is notoriously lawless, the partners say the Puntland region is relatively stable with a strong regional government.

"We are very pleased with the progress made in our concessions and appreciate the excellent support received from both the Puntland Government and the Transitional Federal Government," Africa Oil chief executive Rick Schmitt said.

"Commencement of the seismic program has also reduced the logistical demands on our Puntland infrastructure and we are now working hard to reinstate the drilling program in order to commence drilling during 2008."

Range says the Dharoor and Nogal concessions encompass two highly prospective hydrocarbon basins and cover 81,000 square kilometres.

"The two sedimentary basins were contiguous with the prolific Marib and Masila basins in Yemen during the Jurassic and Cretaceous periods," the company said yesterday.

"Over 9 billion barrels of oil equivalent have been discovered in Yemen but exploration has been limited to date in Somalia.

"Only three wells have been drilled in basinal settings in these concessions before operations ceased in the early 1990s.

"Those wells confirmed thick sedimentary sequences, encountered oil in Cretaceous sandstones and proved the presence of active petroleum systems in both basins."