Core samples for Oceanic Anoxic Event 1a. (IMAGE) University of British Columbia Caption Core samples for Oceanic Anoxic Event 1a. A new study from University of British Columbia and University of Hong Kong indicates volcanism drove rapid ocean deoxygenation during the time of the dinosaurs. Credit: Elisabetta Erba. Credit Elisabetta Erba Usage Restrictions None. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.