Application of long-term chemostratigraphy (organic carbon isotopes) in age calibration of Paleogene mammal faunas

Rapid, ‘short-term’ (10 kyr to several 102 kyr) δ13C - δ18O excursions on various materials (bulk, pedogenetic nodules, specific foraminiferal taxa, secondary layer of brachiopods, dispersed organic matter, wood fragments) have been used for decades as reliable stratigraphic tools during the Paleogene (Late Danian Event, PETM or ETM-1, ETM-2, ETM-3, MECO, Oi-1, …). ‘Long-term’ δ13C isotope trends (102 kyr to several myr) may also provide new stratigraphic insights, particularly in sections without any detailed stratigraphic information. Here we show and discuss the potential uses, biases, limits, and perspectives of long-term δ13C isotope trends on organics, from vertebrate-bearing sections in Morocco, Southern France (Corbières, Minervois, Montpellier area, Provence), Angola and Belgium. Using long-term carbon isotopes on organic matter, terrestrial sections can be correlated with the marine stratigraphic international record. Inter- and intraregional correlations are proposed on the basis of bio- and chemostratigraphic calibration of the various records, particularly with the well-known and continuous sections of the Bighorn Basin, Wyoming (USA). These correlations may contribute to the age calibration of the Paleogene mammal faunas (including endemic faunas) and may shed new light on their evolution in different parts of the world. This work was partly funded by the Belgian Science Policy Office, project BR/121/A3/PALEURAFRICA.

Abstract of an Oral Presentation or a Poster

Paleontology