TITLE:
Temporal Evolution of the Barombi Mbo Maar, a Polygenetic Maar-Diatreme Volcano of the Cameroon Volcanic Line
AUTHORS:
Boris Chako Tchamabé, Takeshi Ohba, Issa , Seigo Ooki, Dieudonné Youmen, Sebastien Owona, Gregory Tanyileke, Joseph Victor Hell
KEYWORDS:
Maar, Eruptive Episodes, Barombi Mbo, Cameroon
JOURNAL NAME:
International Journal of Geosciences,
Vol.5 No.11,
October
27,
2014
ABSTRACT: The Barombi Mbo Maar (BMM), which
is the largest maar in Cameroon, possesses about 126 m-thick well-preserved
pyroclastic deposits sequence in which two successive paleosoil beds have been
identified. The maar was thought to have been active a million years ago.
However, layers stratigraphically separated by the identified paleosoils have
been dated to shed lights on its age and to reconstruct the chronology of its
past activity. The results showed that the BMM formed through three eruptive
cycles: the first ~0.51 Ma ago, the second at ~0.2 Ma and the third ~0.08 Ma
B.P. The ages indicate that the BMM maar-forming eruptions were younger than a
million years. The findings also suggested that the maar is polygenetic. At a
regional scale, the eruptive events would have occurred during some volcanic
manifestations at Mt Manengouba and Mt Cameroon. Therefore, with the decrease
in the recurrence time of eruptions from ~0.3 Ma to 0.1 Ma, and given the
possible relation between its eruptive events and those of its neighboring polygenetic
volcanoes, the BMM is expected to erupt within the next 20 ka.