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De Pesquidoux I Tchaptchet Tchato, Jacqueline Tchakounte, Aurélie Ngamy Kamwa, Jean Pierre Tchouankoue, Soumyajit Mukherjee, 2021. Geometry and kinematics of brittle deformation in the Central Cameroon Shear Zone (Kékem area): Implication for gold exploration within the Central Africa Fold Belt in Cameroon, China Geology, 4, 245-255. doi: 10.31035/cg2020058
Citation: De Pesquidoux I Tchaptchet Tchato, Jacqueline Tchakounte, Aurélie Ngamy Kamwa, Jean Pierre Tchouankoue, Soumyajit Mukherjee, 2021. Geometry and kinematics of brittle deformation in the Central Cameroon Shear Zone (Kékem area): Implication for gold exploration within the Central Africa Fold Belt in Cameroon, China Geology, 4, 245-255. doi: 10.31035/cg2020058
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Geometry and kinematics of brittle deformation in the Central Cameroon Shear Zone (Kékem area): Implication for gold exploration within the Central Africa Fold Belt in Cameroon

  • a.

    Department of Earth Sciences, Faculty of Sciences, University of Yaoundé I, Yaoundé P.O.BOX : 812, Cameroon

  • b.

    Department of Mining Engineering and Minerals processing, Faculty of Mines and Pretrolum Indusries, University of Maroua, Maroua P.O.BOX : 46, Cameroon

  • c.

    Geodynamics Laboratory, Department of Earth Sciences, Indian Institute of Technology Bombay, Powai, Mumbai Maharashtra 410076, India

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Received Date:  15 April 2020
Revised Date:  28 June 2020
Accepted Date:  29 July 2020
Available Online:  28 October 2020
Publish Date:  25 June 2021
    Abstract

  • The Central Africa Fold Belt (CAFB) is a collision belt endowed with gold deposits in Eastern Cameroon area mined for about 50 years. However, favorable areas for gold exploration are poorly known. This paper presents (1) the kinematics of the brittle deformation in the Kékem area in the SW portion of the Central Cameroon Shear Zone and (2) constraints gold mineralization events with respect to the collisional evolution of the CAFB. The authors interpret that the conjugate ENE to E and NNW to NW trending lineament corresponds to the synthetic (R) and the antithetic (R’) shears, which accompanied the dextral slip along the NE to ENE striking shear. The latter coincides with the last 570–552 Ma D3 dextral simple shear-dominated transpression, which is parallel to the Bétaré Oya shear zone hosting gold deposits. Gold mineralizations, which mainly occurred during the last dextral shearing, are disseminated within quartz veins associated to Riedel’s previous structures reactivated due to late collisional activities of the CAFB as brittle deformation. Gold mineralizations occurred mainly during the 570–552 Ma D3 event. The reactivation, which might be due to dextral simple shear during mylonitzation, plausibly remobilized the early gold deposits hosted in syn-compressional rocks and/or possibly focused deep-sourced fluid mixed with those released by dehydration. Therefore, the Central Cameroon Shear Zone where Kékem is located, and which shows similar petrographical and structural features to those controling Batouri gold district, is a target area for gold exploration in Cameroon.

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