Complex and Polygenetic Volcanism

*Updates in Volcanology – Transdisciplinary Nature of Volcano Science*

[89] de Silva SL, Kay SM. Turning up the Heat: High-Flux Magmatism in the Central Andes. Elements. 2018; 14: 245-250. https://doi.org/10.2138/

[90] Vandervoort DS, Jordan TE, Zeitler PK, Alonso RN. Chronology of internal drainage development

plateau, Argentine central Andes. Geology. 1995; 23: 145-148.

10.1130/0091-7613(1995)023<0145:coid

and uplift, southern Puna

gselements.14.4.245

da>2.3.co;2

Altiplano-Puna Magma Body, Central Andes. pure and applied geophysics. 2003; 160: 789-807. 10.1007/pl00012557

[83] Kay SM, Mpodozis C, Gardeweg M. Magma sources and tectonic setting of Central Andean andesites (25.5-28°S) related to crustal thickening, forearc subduction erosion and delamination. In: Orogenic Andesites and Crustal Growth (eds Gómez-Tuena A, Straub SM, Zellmer GF). Geological Society (2013).

303-334. 10.1144/sp385.11

10.1038/s41598-017-09015-5

gselements.11.2.113

10.1038/ncomms13185

[87] Godoy B, McGee L,

[84] Ward KM, Delph JR, Zandt G, Beck SL, Ducea MN. Magmatic evolution of a Cordilleran flare-up and its role in the creation of silicic crust. Scientific Reports. 2017; 7: 9047.

[85] de Silva SL, Riggs NR, Barth AP. Quickening the Pulse: Fractal Tempos in Continental Arc Magmatism. Elements. 2015; 11: 113-118. 10.2113/

[86] Perkins JP, Ward KM, de Silva SL, Zandt G, Beck SL, Finnegan NJ. Surface uplift in the Central Andes driven by growth of the Altiplano Puna Magma Body. Nat Commun. 2016; 7: 13185.

González-Maurel O, Rodríguez I, le Roux P, Morata D, Menzies A. Upper crustal differentiation processes and their role in 238U-230Th disequilibria at the San Pedro-Linzor volcanic chain (Central Andes). Journal of South American Earth Sciences. 2020; 102: 102672. https://doi. org/10.1016/j.jsames.2020.102672

[88] González-Maurel O, le Roux P, Godoy B, Troll VR, Deegan FM,

Menzies A. The great escape: Petrogenesis of low-silica volcanism of Pliocene to Quaternary age associated with the Altiplano-Puna Volcanic Complex of northern Chile (21°10′-22°50′S). Lithos. 2019; 346-347: 105162. https://doi. org/10.1016/j.lithos.2019.105162

**279**

**Chapter 12**

**Abstract**

Type-S and type-MS.

**1. Introduction and geological context**

Cameroon

The Caldera of Mount Bambouto:

Volcanological Characterization

*Ghislain Zangmo Tefogoum, David Guimolaire Nkouathio,* 

Mount Bambouto culminates at 2744 m (Meletan Mountain) where an elliptical caldera of 16 × 8 km is found. Although that caldera has been a subject of numerous scientific works, complementary studies were needed to bring out additional data used to classify it through the Caldera DataBase of Geyer and Marti (2008). It emerges that Bambouto Caldera codes are 2 and 203 because it is respectively located in Africa and Central Africa according to the numbering system developed in the Catalog of Active Volcanoes of the World. The collapse type of the caldera is piecemeal; this relies on the fact that the caldera floor is uneven. Several rocks crop out in the caldera; accordingly, its code is B, I, T, P, and Ig viz. basalts, intermediate rocks, trachytes, phonolites, and ignimbrites. Bambouto depression is the ignimbrite caldera because it is associated with thick ignimbrite sheer, that ruled its collapse. The chemical analysis of rocks reveals that the magmatic series of Bambouto Caldera is of alkaline type. It has been built through the continental rifting of extensional type (RC-EXT). The collapse process has been followed by post-caldera protrusion of trachytic and phonolitic domes; then, its codes are

**Keywords:** caldera, continental rifting, basalts, trachytes, phonolites, ignimbrites,

Internal geodynamics is manifested on the Earth's surface by volcanic phenomena. Most of these phenomena are controlled by volcanoes located in the tectonically and structurally weak areas of the globe, notably accretion zones, convergence zones, and intra-plate zones. Some of these volcanoes are characterized by a simple crater, while others have one or more complex craters (distinguished by the collapse events). These complex craters are defined by one or more calderas [1–4]. The term caldera derives from the depression called Taburiente (Canary Islands) and has been firstly used by [5]. The Caldera de Taburiente in fact, is the frequently quoted example of erosion caldera. Erosion calderas are volcanic depression erosionally formed on the summit or on the flanks of the volcano, which may be several kilometers in diameter [6–8]. However, geologically, calderas are volcanic depressions resulting from the collapse of the roof of the magma chamber due to the rapid

*Armand Kagou Dongmo and Merlin Gountié Dedzo*

and Classification
