RESEARCH ARTICLE Volcanic evolution of central Basse-Terre Island revisited on the basis of new geochronology and geomorphology data J. Ricci 1,2 & X. Quidelleur 1,2 & P. Lahitte 1,2 Received: 17 April 2015 /Accepted: 20 August 2015 /Published online: 7 September 2015 # Springer-Verlag Berlin Heidelberg 2015 Abstract Twenty-six new and seven previous K–Ar ages obtained on groundmass separates for samples from the Axial Chain massif (Guadeloupe, F.W.I.), as- sociated with geomorphological investigations, allow us to propose a new model of the volcanic evolution of the central part of Basse-Terre Island. The Axial Chain is composed of four edifices, Moustique, Matéliane, Capesterre, and Icaque mounts, showing coeval activity from 681±12 to 509±10 ka, which contradicts a previ- ous hypothesis that flank collapse affected them succes- sively. Our geomorphological reconstruction shows that the Axial Chain can be considered as a single large volcano, named the Southern Axial Chain volcano (SCA), rather than a succession of several smaller vol- canoes. It raises questions regarding the formation of a large depression within the SCA volcano, prior to the construction of the Sans-Toucher volcano between 451± 13 and 412±8 ka. Given presently available evidence, a slump affecting the western part of the SCA volcano is the most probable scenario to reconcile the complete age dataset and the present-day morphology of central Basse-Terre. Finally, our study shows that the SCA vol- cano had a post-activity volume of 90 km 3 , implying a construction rate of 0.5 km 3 /kyr. This value strongly constrains interpretations of magma generation processes throughout the Lesser Antilles arc. Keywords Lesser Antilles . Volcanic evolution . K–Ar dating . Surface modeling . Construction rate Introduction The study of present-day morphology of volcanoes provides abundant information about their constructive history and their dismantling, through long-term erosion or instantaneous mass wasting events. Although the current morphology of tropical volcanoes can appear very complex and only poorly preserved, the initial morphology and the volcanic history can be inferred from careful numerical topographic reconstruc- tions based on remnants of post-eruptive surfaces. In the Lesser Antilles volcanic arc, many islands have ex- perienced catastrophic flank collapse events, which have af- fected their morphology (e.g., Deplus et al. 2001; Le Friant et al. 2009; Boudon et al. 2007). Among them, Basse-Terre Island, located in the central part of the arc, displays a strongly eroded morphology. More specifically, its central part, the so- called Axial Chain, seems to have experienced several cata- strophic events. Previous studies suggested that at least three major flank collapses could have affected this volcanic massif (Boudon et al. 2007; Samper et al. 2007), but few studies have been conducted, and its history remains poorly constrained (Blanc, 1983; Samper et al. 2007). In order to better understand the volcanic history of the central part of Basse-Terre Island and to identify possible cat- astrophic events, we combine previous and new K–Ar ages from the Axial Chain with a detailed geomorphological inves- tigation. This allows us to better decipher the eruptive dynam- ics occurring on Basse-Terre Island. Editorial responsibility: A. Gudmundsson * J. Ricci julia.Ricci@u-psud.fr 1 Laboratoire GEOPS, Dpt Sciences de la Terre, University Paris-Sud, CNRS GEOPS Bât. 504 UMR8148, Orsay cedex 91405, France 2 CNRS, Orsay 91405, France Bull Volcanol (2015) 77: 84 DOI 10.1007/s00445-015-0970-7