Sediments in Northern Spain (IMAGE) University of Birmingham Caption These are sediments in northern Spain showing the change from fine-grained sandstones to thick pebble conglomerates characteristic of massive and repeated flood events. Credit Dr Rob Duller, University of Liverpool Usage Restrictions None License Licensed 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.