First chemostratigraphic ( ¦Ä13C, TOC) record of the Early Toarcian Oceanic Anoxic Event from the Southern Hemisphere, Neuqu¨¦n Basin, Argentina

AL-SUWAIDI, A.H., ANGELOZZI, G.N., BAUDIN, F., DAMBORENEA, S.E., HESSELBO, S.P. JENKYNS, H.C., MANCEÑIDO, M.O. & RICCARDI, A.C.

JOURNAL OF THE GEOLOGICAL SOCIETY

GEOLOGICAL SOC PUBL HOUSE

Lugar: Londres; Año: 2010 vol. 167 p. 633 - 636

0016-7649

The first record of the Early Toarcian Oceanic Anoxic Event (~183 Ma) from the Southern Hemisphere is described from the Neuqu¨¦n Basin, Argentina, identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion (d13Corg) in bulk rock and fossil wood. The negative excursion of -6? in bulk organic carbon (falling to -31.3?) crosses the boundary of the tenuicostatum?hoelderi Andean ammonite Zones, equivalent to the tenuicostatum?falciferum/serpentinum Zones of Europe. These data indicate that the Early Toarcian Oceanic Anoxic Event was a global phenomenon.