Torrent in Tolstoj
Mercury is resplendent with flooded impact craters and basins, and Tolstoj can be counted among them. This image shows a portion of that basin's flooded floor, and highlights a good example of the Law of Superposition. The crater to the left clearly post-dates the lava within Tolstoj, as it appears fresh, unfilled, and its ejecta sits atop the surrounding smooth volcanic plains. Yet the crater to the right is barely visible, with only its rim escaping burial by those same volcanic plains. These observations indicate that the crater on the right was formed after the Tolstoj basin, but before the basin was flooded by volcanic material. Finally, the crater on the left formed. A classic Mercurian one-two!
Date acquired: October 10, 2012
Image Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington