metal frame (IMAGE) Johannes Gutenberg Universitaet Mainz Caption A special metal frame allows archaeological excavations of one square meter in the tidal flats. The finds are excavated and documented during low tide. Credit photo/©: Ruth Blankenfeldt Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND 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.