Sedimentology, palaeoenvironments and biostratigraphy of the Pliocene–Pleistocene carbonate platform of Grande‐Terre (Guadeloupe, Lesser Antilles forearc)

Abstract

International audiencePliocene and Pleistocene deposits from Grande-Terre (Guadeloupe archipelago, French Lesser Antilles) provide a remarkable example of an isolated carbonate system built in an active margin setting, with sedimentation both controlled by rapid sea-level changes and tectonic movements. Based on new field, sedimentological and palaeontological analyses, these deposits have been organized into four sedimentary sequences (S1 to S4) separated by three subaerial erosion surfaces (SB0, SB1 and SB2). Sequences S1 and S2 ('Calcaires inférieurs à rhodolithes') deposited during the late Zanclean to early Gelasian (planktonic foraminiferal Zones PL2 to PL5) in low subsidence conditions, on a distally steepened ramp dipping eastward. Red algal-rich deposits, which dominate the western part of Grande-Terre, change to planktonic foraminifer-rich deposits eastward. Vertical movements of tens of metres were responsible for the formation of SB0 and SB1. Sequence S3 ('Formation volcano-sédimentaire', 'Calcaires supérieurs à rhodolithes' and 'Calcaires à Agaricia') was deposited during the late Piacenzian to early Calabrian (Zones PL5 to PT1a) on a distally steepened, red algal-dominated ramp that changes upward into a homoclinal, coral-dominated ramp. Deposition of Sequence S3 occurred during a eustatic cycle in quiet tectonic conditions. Its uppermost boundary, the major erosion surface SB2, is related to the Cala1 eustatic sea-level fall. Finally, Sequence S4 ('Calcaires à Acropora') probably formed during the Calabrian, developing as a coral-dominated platform during a eustatic cycle in quiet tectonic conditions. The final emergence of the island could then have occurred in late Calabrian times

Pliocene to Pleistocene vertical movements in the forearc of the Lesser Antilles subduction: insights from chronostratigraphy of shallow-water carbonate platforms (Guadeloupe archipelago)

“…Both sequences are incomplete and display only aggrading pattern, suggesting that erosional SB0 and SB1 were generated by local tectonic uplifts. Biostratigraphic data of Cornée et al (2012) for the top of sequence S2 and the base of sequence S3 in the Anse à l'Eau section (Fig. 2) are in accordance with those of Andreieff et al (1989).…”

“…between 1.81 and 0.78 Ma) according to the study of the La Simonière core by Andreieff et al (1989), whereas unit 5 may be dated at c. 330 ka (late Pleistocene) according to Feuillet et al (2002Feuillet et al ( , 2004. recently, Cornée et al (2012) and Lardeaux et al (2013) showed that the carbonate platforms of Grande-Terre and La Désirade comprise four sedimentary sequences separated by erosional unconformities (Fig. 2).…”

“…unit 3 is composed of red algal shallow-water rudstone to boundstone (Calcaires supérieurs à rhodolites Formation) and is dated to Zones PL6-Pt1a (late early-middle Pleistocene interval). unit 4 corresponds to a prograding reefal platform up to 30 m thick Andreieff et al (1989), Léticée et al (2005) and Cornée et al (2012).…”

Tectonic and sedimentary architecture of the Karukéra spur: A record of the Lesser Antilles fore-arc deformations since the Neogene

“…They are interpreted as a Highstand Systems Tract HST 4 . Such Agaricia coral reefs are known onland at Grande-Terre and date early Calabrian (Cornée et al, 2012;Münch et al, 2014). SB4 is characterised by severe erosion in northeast NAP and Flandre Basin, i.e., along the tip of the La Désirade scarp, as well as strong reflections and local truncations indicative of erosion along the western border of the spur at NAP and CAP.…”

Morphology and genetics reveal an intriguing pattern of differentiation at a very small geographic scale in a bird species, the forest thrush Turdus lherminieri

“…For the last 5 Myr, GT had a marine history involving the deposit of a shallow water carbonate platform and several aerial exposures related to either uplifts or global sea-level changes (Cornée et al, 2012). This part of Guadeloupe became durably emerged around 330 000 years ago (Feuillet et al 2004; but see Cornée et al (2012) and Münch et al (2013) who recently proposed an older age of 1 Myr). BT, in contrast, originated from five volcanic complexes developing over the last 2.8 Myr (Gailler et al, 2013).…”