Green Shard from Sudbury (IMAGE) Trinity College Dublin Caption This is a photomicrograph of a vesicular green shard from the Onaping Formation of the Sudbury impact basin. Credit Paul Guyett, Trinity College Dublin. 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.