At attempt is made here to provide a comprehensive The Basement "massifs" roughly delimit the main account in book form of the Petroleum Geology of sedimentary areas of the: Nigeria, a country which in 1979 was the world's 1. ABAKALIKI, BENUE, GONGOLA AND YOLA sixth largest oil producer and rated the twelfth gIant TROUGHS petroleum province of the world by Ivanhoe (1980) 2. BIDA OR MIDDLE NIGER BASIN in terms of known recoverable resources (cumulatIve 3. SOKOTO EMBAYMENT OF THE IULLEM production + proven + probable reserves) of oil and MEDEN BASIN 4. BORNU-CHAD BASIN gas. . 5. DAHOMEY BASIN...