Geologic and Metallogenic Framework of North Africa

Abstract

North Africa is noteworthy for having a great diversity of geology and mineral resources. Geologically, the region contains numerous terranes that contain rocks ranging in age from Archean to Quaternary, including diverse igneous, sedimentary, and metamorphic lithologies. Major geological features were built during the main phases of Proterozoic and subsequent Phanerozoic orogenies, the break-up of the supercontinents Rodinia, Gondwana, and Pangea, and during the opening and closing of major ocean basins such as the Iapatus, Atlantic, Pacific, and Tethys. Three major tectono-stratigraphic domains are recognized (1) the Precambrian province that includes the African-Nubian Shield (ANS) to the east and the West African Craton (WAC) to the west, and the intervening Tuareg Shield and "Saharan Metacraton"; (2) the Variscan (Paleozoic) fold belt; and (3) the Atlas-Alpine (Mesozoic-Cenozoic) system. Mineral deposits of North Africa formed in a variety of geologic settings at different time periods from Archean to Quaternary. Mineral commodities including gold, silver, cobalt, nickel, chromium, arsenic, copper, lead, zinc, iron, and many other elements. Major deposit types present in the region are (1) orthomagmatic Cr-Ni-platinum group elements (PGE); (2) rare-metal granites and related rare-element pegmatites; (3) volcanic-hosted massive sulphide (VHMS); (4) sedimentaryexhalative (SEDEX); (5) orogenic and intrusion-related gold; (6) iron oxide-copper-gold (IOCG); (7) banded iron formation (BIF); (8) Mississippi Valley-type (MVT) lead-zinc; (9) sediment-hosted stratiform copper;Electronic supplementary material The online version of this chapter

Compositional characteristics of mineralised and unmineralised gneisses and schist around the Abansuoso area, southwestern Ghana

“…Smith et al 2016; Agbenyezi et al 2020). In recent years, gold resources in the Birimian granitoid have become viable targets for exploration in an effort to maximise the gold ore resource base and boost productivity (Amponsah et al 2016; Bouabdellah and Slack 2016; Takyi-Kyeremeh et al 2019). The Chirano, Nhyiaso, Ayanfuri, and Ayankyerim gold deposits in the western portion of the Sefwi and Ashanti Belts are discussed as prime examples of gold-bearing granitoid bodies (Allibone et al 2004; Fougerouse et al 2017).…”

The Roc Blanc orogenic Pb-Zn-Ag-Au deposit (Morocco): a product of metamorphic dehydration and CO2 devolatilization during exhumation of the Variscan Jebilet massif

“…The Roc Blanc deposit is one of numerous Pb-Zn-Ag-Au ± Cu ± F ± Ba vein deposits that are widely distributed throughout the main Paleozoic inliers of Morocco (Margoum et al 2015;Bouabdellah and Slack 2016), within the central part of the Jebilet orogen, ca. 20 km northwest of Marrakech (Fig.…”

Mineralogy, Fluid Inclusion, and C-O-Sr Isotope Geochemistry to Unravel the Evolution of the Magmatic-Hydrothermal System at the Igoudrane Silver-Rich Deposit (Imiter District, Eastern Anti-Atlas, Morocco)

“…Silicification is the early alteration type (Figure 4F) and led to development of milky and gray quartz veins to which the early silver-bearing stage I is related to. This stage, which gave rise predominantly to development of NEtrending dextral mineralized veins filled by quartz and associated silver-baring sulfide and sulfosalt assemblages, occurred in response to NW-SE to WNW-ESE transpressional tectonics [4,42,43,51]. Conversely, carbonitization is by far the dominant alteration type (Figure 4G) in the Igoudrane mine.…”