RT Journal Article SR Electronic T1 First record of the Early Toarcian Oceanic Anoxic Event from the Southern Hemisphere, Neuquén Basin, Argentina JF Journal of the Geological Society JO Journal of the Geological Society FD Geological Society of London SP 633 OP 636 DO 10.1144/0016-76492010-025 VO 167 IS 4 A1 Al-Suwaidi, A.H. A1 Angelozzi, G.N. A1 Baudin, F. A1 Damborenea, S.E. A1 Hesselbo, S.P. A1 Jenkyns, H.C. A1 Manceñido, M.O. A1 Riccardi, A.C. YR 2010 UL http://jgs.lyellcollection.org/content/167/4/633.abstract AB The first record of the Early Toarcian Oceanic Anoxic Event (c. 183 Ma) from the Southern Hemisphere is described from the Neuquén Basin, Argentina, identified chemostratigraphically on the basis of a relative increase in marine organic carbon and a characteristic negative carbon-isotope excursion (δ13Corg) 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.Supplementary material: A detailed stratigraphic log, chemostratigraphic data and nannofossil data are available at http://www.geolsoc.org.uk/SUP18411.