The Mediterranean-Atlantic strait closed tight time and time again, and the Mediterranean Sea, for the first time and then repeatedly, partially desiccated. The basin was finally isolated from the Atlantic Ocean for a longer period, between 5.59 and 5.33 million years ago, resulting in a large or smaller (depending on the scientific model applied) lowering of the Mediterranean sea level. During the initial, very dry stages (5.6–5.5 Ma), there was extensive erosion, creating several huge canyon systems (some similar in scale to the Grand Canyon) around the Mediterranean. Later stages (5.50–5.33 Ma) are marked by cyclic evaporite deposition into a large "lake-sea" basin ("Lago Mare" event).