Physical Volcanology of Pyroclastic Tephra Deposit at Batoke Mt. Cameroon, West Africa: An Over View.

L Nche,Ce Suh,Cn Ngwa

doi:10.4314/gjgs.v11i1.3

Abstract

In this contribution, we report an overview of the physical attributes of pyroclastic deposit at the foot of Mt. Cameroon, West Africa. In the deposit three facies types; which are the lava flow, the lapilli and ash are common. The ash is the dominant facies and occurs irregularly in alternation with the lapilli. The most common types of depositional features include cm-dm planar beds and impact sags. We infer from field observations of facies types, clasts types and depositional features that this deposit is a phreatomagmatic fall deposit which resulted from an interaction between lava flow and surface water. The occurrence in the deposit of accretionary lapilli, impact sags, fragments of country-rock and juvenile clasts is ambiguous evidence in support of phreatomagmatic activity. The presence of a lava flow flanked by the tephra pile, the lack of accidental clasts, and the scarcity of bombs are evidence in support of a surface water-lava flow interaction.KEY WORDS: Pyroclastic Deposit, Batoke, Mt. Cameroon,

Highlights

In this contribution, we report an overview of the physical attributes of pyroclastic deposit at the foot of Mt
In this paper we present a volcanological study of pyroclastic deposits at the foot of Mt
Geological Setting The Cameroon Volcanic Line (CVL) is a 1600 km long chain of Cenozoic volcanoes that extends from the island of Annobon in the Gulf of Guinea into mainland Africa (Fig. 1)

Summary

Introduction

We report an overview of the physical attributes of pyroclastic deposit at the foot of Mt. The only presently active volcano on the CVL is a stratovolcano with an estimated volume and height of about 1200 -1250km and 4095 m, respectively (Suh et al, 2003) This mountain rises between two sedimentary basins: the Douala, to the southeast and the Rio del Rey, to the northwest. With an annual population growth rate of 2.7% and much infrastructural development at the foot and flanks of this volcano, there is a need for constant monitoring of the edifice to allow for hazard mitigation and management campaigns This requires the use of many methods amongst which is the physical study of erupted material; the aim of the present work. The total surface area covered by this deposit could not be ascertained partly because of human settlements

Findings

Discussion

Conclusion