Credit: NASA/JPL-Caltech/Stony Brook University
Diagram of Lake Stratification on Mars: This diagram presents some of the processes and clues related to a long-ago lake on Mars that became stratified, with the shallow water richer in oxidants than deeper water was. The sedimentary rocks deposited within a lake in Mars’ Gale Crater more than 3 billion years ago differ from each other in a pattern that matches what is seen in lakes on Earth. As sediment-bearing water flows into a lake, bedding thickness and particle size progressively decrease as sediment is deposited in deeper and deeper water as seen in examples of thick beds from shallowest water, thin beds from deeper water and even thinner beds from deepest water.