Though commercial production of oil and gas in Ghana
commenced in December 2010, the exploration of the commodity had commenced over
a century before then. Ghana has four sedimentary basins namely the Cote
d’Ivoire-Tano Basin (which includes the Cape Three Points sub-basin), the
Central (Saltpond) Basin, the Accra/Keta Basin and the inland Voltaian Basin
(GNPC 2008). Exploration activities have been undertaken in all the four
sedimentary basins in the past. A brief account of the exploration history in
Ghana is hereby presented;
The Initial Phase 1896-1967
The first oil and gas exploration
wells were drilled in onshore Tano basin in the Western Region of Ghana. The
prospects for oil were revealed by the seepages of oil and gas that was found
by explorers in the area. During this period, exploration activities were intermittent and unsustained with the
activities limited to onshore. The first documented discovery well in Ghana was drilled at a total
depth of 35metres and produced 5bopd between 1896 and 1897 (GNPC 2008).
The Second Phase 1968 – 1980
During this period, there was intense exploration activity offshore
culminating in the drilling of the first offshore well in the Saltpond basin in
1970. There was a further discovery of an oil and gas field in the North Tano
basin. The first well was drilled in the Voltaian basin during this period. In
November 1978, the first deepwater well, South Discove, was drilled offshore
Cape Three Points in 892metres of water. Additionally, 2D seismic data was used
in mapping both offshore and onshore prospects. This set the tone for the next
phase of exploration.
The Third Phase 1981 – 2000
This period saw the establishment of a new regulatory, fiscal and
legal framework by the government to accelerate E&P activities in Ghana.
The current petroleum E&P Laws (PNDL Laws 64 and 84) were enacted in the
early eighties leading to the establishment of the GNPC in 1985. The Petroleum
Income Tax Law, PNDC Law 188 was passed to provide a separate tax regime for
E&P activities in Ghana.
The GNPC spearheaded an intensive Exploration Program and further
undertook a comprehensive promotion Program through the acquisition, processing
and interpretation of the first 3D seismic over the South Tano field. A number
of deepwater exploration activities were undertaken in the 1990s but none of
them were declared commercial.
The Current Phase 2001- Date
During this period, the government restructured the GNPC to focus its
efforts on exploration of oil and gas through training of staff and updating of
their technology. The focus of exploration activities was on Deepwater with
agreements being signed with Kosmos Energy, Tullow Oil and Anadarko for E&P
activities in the shallow water Tano, deep water Tano and West Cape Three
Points blocks. In June 2007, the Jubilee oil and gas field was discovered following
drilling up to 1700m in deepwater Tano and West Cape Three Points