First palynostratigraphical evidence for a Late Eocene to Early Miocene age of the volcano-sedimentary series of Dschang, western part of Cameroon and its implications for the interpretation of palaeoenvironment Bessong Moise a,b, ⁎, Hell Joseph Victor a , Susanne Feist Burkhardt b,c , Elias Samankassou b , Mouloud Bennami d , Nolla Junior Désiré a , Mbesse Cecile Olive e , Thierry Adatte f , Rossana Martini b , Michel Brunet d,g a Institute for Geological and Mining Research (IRGM), B.P. 4110 Yaoundé, Cameroon b Section of Earth and Environmental Sciences, Department of Earth Sciences, University of Geneva, 13, Rue des Maraichers, 1205 Geneva, Switzerland c SBF Geological and Consulting Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany d Institute of Palaeoprimatology, Human Palaeontology: Evolution and Palaeoenvironments, UMR CNRS 7262 INEE, UFR SFA, University of Poitiers, France e Department of Geosciences, University of Douala, B.P. 2701 Douala, Cameroon f Institute of Earth Sciences (ISTE), University of Lausanne, Building Géopolis, 1015 Lausanne, Switzerland g Collège de France, Paris, France abstract article info Article history: Received 4 July 2016 Received in revised form 30 May 2017 Accepted 10 July 2017 Available online xxxx The volcano-sedimentary infill of the Dschang basin in the Western part of Cameroon is poorly known. The pres- ent study provides the first biostratigraphical data of the volcano-sedimentary sequence and allows constraining the age and the position of this basin within the regional context of Central Africa. The studied sequence is com- posed of three depositional units. The first unit is a fining-upwards sequence of coarse-grained sandstone that gets finer towards the top, passing to thick layers of fossiliferous claystone. The second unit is strongly affected by volcanic activity and consists of a volcano-sedimentary sequence. The third unit is marked by basaltic volca- nism and covers the series. Diverse and well-preserved palynomorphs were recovered and are used to provide valuable information for age determination of the Dschang volcano-sedimentary sequence, namely to be of late Eocene- Early Miocene age. The recovered spores, pollen, green algae and fungal remains from the bottom of the sequence include Bombacidites spp., Clavainaperturites cf. clavatus, Crototricolpites sp., Perfotricolpites digitatus, Proteacidites spp., Psilastephanocolporites minor, Psilastephanocolporites spp., Retitrescolpites spp., Retitricolporites irregularis, Retitricolporites spp., Retitriporites sp., Spirosyncolpites bruni (probably synonymous to Spirosyncolpites spiralis), Striatopollis bellus, (considered synonymous to Striatopollis catatumbus), Striatopollis sp., Tetracolporites quadratus, Tetratricolporites sp., ?Verrutricolporites rotundiporis, Cyathidites sp., Laevigatosporites spp., Polypodiaceoisporites spp., Verrucatosporites usmensis, Verrucatosporites spp., Botryococcus sp., Tasmanites sp., and fungal remains. The samples are assigned to the Verrucatosporites usmensis Zone of Salard-Cheboldaeff (1979). The palynological assemblages are similar to those of other Late Eocene to Early Miocene palynological records from the West, Cen- tral and Northern African basins. Study of the organic matter by pyrolysis Rock-Eval 6 (Types I, II and III), the sed- imentological setting, the palynofacies and the palynomorph assemblages show evidences of tidal influence (presence of the prasinophyte Tasmanites) in an active continental margin (semi-arid to humid lacustrine depo- sitional environment). The Ngoua sedimentary sequence is fluvio-lacustrine, and believed to have witnessed some occasional marine incursions possibly during the opening of the Central Atlantic Ocean (CAO) and strongly disturbed later by intense volcanic activity. © 2017 Elsevier B.V. All rights reserved. Keywords: Eocene Miocene Palynology Palaeoenvironment Cameroon Ngoua sedimentary sequence 1. Introduction The Cameroon Volcanic Line (CVL, Fig. 1) includes all volcanic zones located between the Gulf of Guinea and the Lake Chad and hosts several sedimentary basins. Volcanic events along this line have been studied previously and the oldest is dated by many authors as Cenozoic Palaeogeography, Palaeoclimatology, Palaeoecology xxx (2017) xxx–xxx ⁎ Corresponding author at: Institute for Geological and Mining Research (IRGM), BP 4110 Yoaundé, Cameroun. E-mail addresses: moisebessong@gmail.com, bessong_moise@yahoo.fr (B. Moise). PALAEO-08359; No of Pages 14 http://dx.doi.org/10.1016/j.palaeo.2017.07.009 0031-0182/© 2017 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Please cite this article as: Moise, B., et al., First palynostratigraphical evidence for a Late Eocene to Early Miocene age of the volcano-sedimentary series of Dschang, western ..., Palaeogeogr. Palaeoclimatol. Palaeoecol. (2017), http://dx.doi.org/10.1016/j.palaeo.2017.07.009