Map showing subtle terraces on the north side of Yellowstone Lake

Shaded relief map based on high-resolution topographic data from lidar and showing subtle terraces on the north side of Yellowstone Lake (a few example terraces are marked by yellow arrows and traced by dashed and dotted white lines). Each terrace represents a high-stand of lake water, which is caused by water backing up into the lake because caldera uplift raised the level of the lake outlet in the past.  The presence of these terraces, and the fact that they are tilted slightly towards the caldera, implies that the caldera has subsided since they formed several thousand years ago.