Geology, Palaeodeposition and the Involvement of Rhyolite Melts in the Petrogenesis of the Tabenken Coal Seam in the North West Region of Cameroon  

作　　者：Abimnui Norine Wendi Njilah Isaac Konfor Yongue Fouateu Rose Mosere Felicia Nanje Nfor Bruno Ndicho Abimnui Norine Wendi;Njilah Isaac Konfor;Yongue Fouateu Rose;Mosere Felicia Nanje;Nfor Bruno Ndicho(Department of Earth Sciences, Faculty of Science, The University of Yaounde 1, Yaounde, Cameroon;Department of Geology, Chukwuemeka Odumegwu Ojukwu University, Anambra State, Nigeria)

机构地区：[1]Department of Earth Sciences, Faculty of Science, The University of Yaounde 1, Yaounde, Cameroon [2]Department of Geology, Chukwuemeka Odumegwu Ojukwu University, Anambra State, Nigeria

出　　处：《Journal of Geoscience and Environment Protection》2022年第4期111-126,共16页地球科学和环境保护期刊（英文）

摘　　要：The discovery of patches of a coal deposit and other associated sedimentary and volcanic rocks in Tabenken North West Cameroon has raised the question of the geology and palaeoenvironment of that area. This Region, which is predominantly characterized by a granitoid basement of Precambrian age is in most parts overlain by Cenozoic basalts, hawaite, mugearite, trachyte and rhyolites. Volcanic outpours modified the geomorphology of the area into a series of hills and valleys. We investigated the geological setting in view of reconstituting the palaeodepositional environment of the Tabenken Coal Seam. Field studies show that the coal occurs in form of inclusions within sandstones, high grade coal bed, massive beds exposed by landslides and in alkali rhyolites. The results of Ultimate analyses of the coal indicate bituminous coal with 58% Carbon, sulfur content as low as 0.12% and ash content of 17%. The occurrence of a well stratified dark volcanic ash bed in the area is interpreted to be an interactive product of the explosive volcanic activity and weathering. Field examination of the area suggests that it was a micro-continental sedimentary palaeo-basin which was later infilled with Cenozoic volcanic outpours which probably modified the chemistry of the coal to meta-anthracites. The actual ages of the coal as well as the associated sedimentary units have not been established, meanwhile, the volcanism started some 31 ma ago.The discovery of patches of a coal deposit and other associated sedimentary and volcanic rocks in Tabenken North West Cameroon has raised the question of the geology and palaeoenvironment of that area. This Region, which is predominantly characterized by a granitoid basement of Precambrian age is in most parts overlain by Cenozoic basalts, hawaite, mugearite, trachyte and rhyolites. Volcanic outpours modified the geomorphology of the area into a series of hills and valleys. We investigated the geological setting in view of reconstituting the palaeodepositional environment of the Tabenken Coal Seam. Field studies show that the coal occurs in form of inclusions within sandstones, high grade coal bed, massive beds exposed by landslides and in alkali rhyolites. The results of Ultimate analyses of the coal indicate bituminous coal with 58% Carbon, sulfur content as low as 0.12% and ash content of 17%. The occurrence of a well stratified dark volcanic ash bed in the area is interpreted to be an interactive product of the explosive volcanic activity and weathering. Field examination of the area suggests that it was a micro-continental sedimentary palaeo-basin which was later infilled with Cenozoic volcanic outpours which probably modified the chemistry of the coal to meta-anthracites. The actual ages of the coal as well as the associated sedimentary units have not been established, meanwhile, the volcanism started some 31 ma ago.

关 键 词：Tabenken Palaeodepositional Environment Bituminous Coal ANTHRACITE Meta-Anthracite 

分 类 号：P58[天文地球—岩石学]