Nos tutelles

CNRS

Rechercher




Accueil > À noter > Séminaires de Caen

Kevin Pedoja le 20 novembre

Kevin Pedoja présentera, vendredi 20 novembre à 13h30 en salle de réunion du M2C Caen, un séminaire portant sur :

Sequences of coral reef terraces from Buton and Tukang Besi archipelagos, Southeast Sulawesi, Indonesia : the most comprehensive record of Plio-Quaternary highstands ?

Résumé :
The Indonesian archipelago displays spectacular Late Cenozoic sequences of marine and coral reef terraces, in particular on the Tukang Besi and Buton archipelagos (SE Sulawesi). In this area, the uplift of submarine hills and other topographic highs during the late Cenozoic led to major geographic changes : reef platforms and/or table reefs were formed on top of topographic highs, then sequences of coral reef terraces emerged and covered the rising slopes of the islands. Remote sensing imagery associated to field mapping and U/Th dating of these sequences of terraces enabled the identification of at least 23 islands covered with fossil reefs of SE Sulawesi. In SE Buton, a sequence includes more than 40 successive terraces and reaches a maximum elevation of 650 +/-10 m. More specifically, on the Sampolawa peninsula, a sequence includes some 20 strandlines and culminates at 430 +/- 10 m. On the latter peninsula, U/Th dating of four low-standing terraces suggest that they were formed during the last four interglacial periods (MIS 5e, 7, 9 and 11), yielding an average mean uplift rates of 0.12+/-0.04 mm/yr. By extrapolation of these uplift rate, the sequences of SE Buton could potentially provide a record of sea level highstands for the last 3.5 Ma, consequently making these sequences the most comprehensive known record of Plio-Quaternary sea level stands worldwide.

Agenda

Ajouter un événement iCal