The map depicts the different kinds of rocks emerging on Africa's surface. Each kind of rock is represented by a conventional colour, referring to the geological period. The map is one of the tables made by the TCI Cartographic Office for the Italian Encyclopedia of Giovanni Treccani Institute
<bdi><a href="https://www.wikidata.org/wiki/Q3457150" class="extiw" title="d:Q3457150"><span title="Italian geographer, geologist and paleontologist (1882-1938)">Giuseppe Stefanini</span></a>
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CC BY-SA 4.0
<bdi><a href="https://en.wikipedia.org/wiki/en:Touring_Club_Italiano" class="extiw" title="w:en:Touring Club Italiano"><span title="large publisher">Touring Club Italiano</span></a>
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