One of the many orogeny cycles in Central Africa is the Pan‐African orogeny which took place during the Neoproterozoic era. In central Cameroon, the reworked materials are Archean to Palaeoproterozoic rocks of sedimentary and magmatic origin and subsequent granitoids. The metadiorite of Meiganga is a syntectonic magmatic rock, affected by three deformational phases. It is characterized by a schistosity highlighted by a banded structure related to migmatization and made up of green hornblende, biotite, plagioclase, quartz, chlorite, opaques minerals, apatite, zircon, and titanite. Zircon grains of the metadiorite are prismatic or roundish. Internally, they show oscillatory zonation, blurred oscillatory zonation, and sector zoning. Some grains portray an outer cathodoluminescence bright band with blurred oscillatory zonation and which transgress the inner oscillatory domain; zircons contain inclusions or are inclusion free. Laser‐ablation microprobe‐inductively coupled plasma‐mass spectrometry U–Pb data allow in relation with the internal structure of the zircon to decipher many tectono‐metamorphic steps in the Ediacaran phase of the Pan‐African Orogeny: (a) syntectonic emplacement of the dioritic protolith at 637 ± 5 Ma; (b) syn‐D2 melting process at 623 ± 2 Ma; (c) D3 time interval between 608 ± 2 and 562 ± 6 Ma; and (d) maximum age of the dextral movement of the regional shear zone at 570 ± 8 Ma. Ages founded in the studied metadiorite sample are recorded individually in different area of the Adamawa‐Yadé area of the Central African Fold Belt and the Borborema Province of NE Brazil, showing that the two domains underwent the same tectono‐metamorphic history during the Ediacaran period.

The Doua area belongs to the Adamawa-Yadé domain (AYD) of the Central African Fold Belt (CAFB) in Cameroon. It is crossed by the Central Cameroonian Shear Zone (CCSZ). The purpose of this research is to determine the tectonic setting of granites of the studied area, based on their petrography, zircons feature and their ages. Petrographicaly, the Doua area is made up of plutonic rocks hosted in an ortho or paraderivative metamorphic basement. Amphibole-biotite granite (ABG) and biotite-muscovite granite form hills and crop out on the hill side, as flagstones in the valley or river bed, and as huge blocks. Amphibole-biotite granite is granular in texture and made up of amphibole, biotite, feldspar, accessory minerals (Sphene, zircon, and apatite) and secondary minerals (sericite). Biotite-muscovite granite (BMG) is granular to granular porphyritic in texture, made up of biotite, muscovite, plagioclase, K-feldspar, quartz, accessory minerals (zircon, opaques minerals) and secondary minerals (chlorite, sericite). ABG show elongated zircon grains with well-developed magmatic oscillatory zonation. LA-ICP-MS U-Pb data from these zircons define a concordia age of 607 ± 3 Ma and considered as crystallization age of the granite. BMG shows zircon with various shape and various internal structures (oscillatory zonation, sector zonation, blurred oscillatory zonation …) which are divided into two sets. The first set regarded as xenocryst from Paleoproterozoic granitoids emplaced at 2126 ±36 Ma or from sediments which detritus comes from such granitoids. The second set of zircons shows effects of recent lead lost and a subconcordant U-Pb age of 646 ± 39 Ma . ABG was emplaced during the D3 deformational phase, date at 607 ± 3 Ma , while BMG was trigger because of syn-D1 activity of the CCSZ at 647 ±46 Ma in association with the collisional process.

The border of Cameroon and Chad is characterized by a Precambrian basement straddling the Touboro-Baïbokoum area; this basement is made up of gneiss, amphibolite and granitoids (granite, syenite, granodiorite). The studied rocks display high-K calk-alcalcaline to shoshonitic characteristic. Granitoids are metaluminous. Rocks under study derived from partial melts from metabasaltic to metatonalitic sources, and partial melts from metagreywackes. They shear the same origin as many granitoids describe westward in the Meiganga area and west Cameroon. This shows that the basement straddling the Touboro-Baïbokoum area belongs to the Adamawa-Yadé Domain of the Central African Fold Belt.

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