Remote sensing satellite-based structural/alteration mapping for gold exploration in the Ketté goldfield, Eastern Cameroon. (December 2021)

• Record Type: Journal Article
• Authors: Ngassam Mbianya, Ghislain; Ngnotue, Timoleon; Takodjou Wambo, Jonas Didero; Ganno, Sylvestre; Pour, Amin Beiranvand; Ayonta Kenne, Patrick; Fossi, Donald Hermann; Wolf, Isabelle D.
• Is Part Of: Journal of African earth sciences. Volume 184(2021)
• Publication Date: 2021-12
• Subjects: Remote sensing -- Lineament -- Alteration mapping -- Gold exploration -- Sub-tropical region -- Eastern Cameroon; Earth sciences -- Africa -- Periodicals; Earth sciences -- Middle East -- Periodicals; Geology -- Africa -- Periodicals; Geology -- Middle East -- Periodicals; Sciences de la terre -- Afrique -- Périodiques; Sciences de la terre -- Moyen-Orient -- Périodiques; Géologie -- Afrique -- Périodiques; Géologie -- Moyen-Orient -- Périodiques; Earth sciences; Geology; Africa; Middle East; Periodicals; Electronic journals; 556.05
• DOI: 10.1016/j.jafrearsci.2021.104386
• Languages: English
• ISSNs: 1464-343X

Abstract

Abstract: In-situ mineral prospecting studies in the tropics face challenging environmental conditions leading to paucity of data and structural mapping of new mineralizations. Here we present the case of the tropical mining goldfield of Ketté in Cameroon to demonstrate remote sensing techniques for mineral exploration purposes. In this investigation Visible Near Infra-Red (VNIR) and Short Wave Infra-Red (SWIR) bands of Landsat-8 (OLI) and Landsat-7 (ETM+) images were used with field data for lineaments and hydrothermal alterations mapping. Semi-automatic and automatic extraction methods were applied through sobel directional filters to detect the contours in the image. PCA, MNF transformation and a band ratio of 4/2, 6/5 and 6/7 were applied to map alteration minerals. The result revealed NE-SW to ENE-WSW main trends. Gold mineralization occurrences are spatially associated with WNW-ESE to NW-SE (110°–140°) ranging lineaments/faults and show a strong correlation with medium to high lineament density zones. Hydrothermal alteration minerals are spatially associated closely with gold occurrences and known mining sites that are structurally controlled by the NE-SW to ENE-WSW shear zone. The high-prospect zones for gold exploration are located along the Mama and Molé fault, Ngoubésseli, Boubara-Koumbé Tiko, Gwé, and Ndambi I-Tezoukpé. Highlights: Remote sensing for structural-hydrothermal alterations mapping in sub-tropical region. Geostatistical approach to analyse the spatial distribution of highlighted fracture. Gold occurrences shows strong correlation with medium to high lineament density zones. Hydrothermal minerals show a closely spatial association with known gold mining sites.