Ghana, about the size of Oregon (238,000 km2), is located in the area of about 1°E–3°W longitude and 5°N–11°N latitude, on the West African Gulf of Guinea. The southern part of the country is primarily equatorial rain forest, partially cleared for farming in many areas. Northern Ghana and some narrow rain shadow zones along the coast are savannah, as West Africa tends to be progressively drier northward into the Sahel and into the Sahara itself.
There are few rock outcrops, especially in the southern portion of the country, where beneath the thick vegetation lies up to 60 m of lateritic soil and weathered rock overlying bedrock. Surface geological mapping is thus very difficult over most of the country, as outcrop searches and trenching, perhaps even boring through the overburden, take a great deal of time and effort, not to mention the cost in funds and manpower to a developing country.