Experiment Showing Stepped Fan (IMAGE) Virginia Tech Caption This photograph shows a delta (~40 cm across) with steps (about 2 cm in the highest places) draped over a mock crater formed in the Eurotank at Utrecht University. The unusual "stair step" shape is due to the fan depositing at the same time as the water level rises. Then the water flow into the channel is stopped and the water in the crater is allowed to drain by seeping into the floor. Credit Erin Kraal Usage Restrictions Use with report on research by Erin Kraal 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.