A numeric code identifies each region, province, total petroleum system, and assessment unit; these codes are uniform throughout the project and throughout all publications of the project. The code used in this study is as follows:
Cretaceous - Меловой период
Figure 1. Gulf of Guinea Province (7183) in west-central Africa and locations of oil and gas field centerpoints
Figure 3. Major features of the Gulf of Guinea Province, west Africa: Benin, Central, Ivory Coast, Keta, Saltpond, Tano, and Volta Basins, Cape Three Points, major fracture zones, and approximate locations of exploration wells and of the oil and gas discoveries and fields mentioned in the text. Mid-Atlantic Ridge and fracture zones shown in index map
Figure 5. Paleogeographic stages in the separation of Africa and South America during the Cretaceous. Modified from Tissot and others (1980).
http://pubs.usgs.gov/bul/2207/C/http://pubs.usgs.gov/bul/2207/C/pdf/b2207c_508.pdf