Figure: (left) Aerial image overview of the Sentinel rock avalanche deposit and source area at the mouth of Zion Canyon. (right) Topographic map of the same; points are samples for cosmogenic dating. Red dashed line is the mapped or presumed deposit boundary; orange line shows the slide scarp.
 
Figure: (left) Reconstructed original thickness of the Sentinel rock avalanche deposit, shown with estimated basal topography. (right) Difference between post-slide surface and modern topography revealing eroded areas of the deposit; new deposits are shown by negative numbers.
 
Figure: (left) Animation of the Sentinel rock avalanche dynamics; simulated duration is 90 s and the results have been sped up 20x for viewing purposes. (right) Sentinel Lake at its proposed high-stand, shortly after the rock avalanche, and its long-term stable stand at slightly lower elevation.
 
Figure: (top) Overview of the Sentinel rock avalanche deposit looking north. (bottom) Cross-sectional view of rock avalanche debris exposed in the Virgin River gorge near the mouth of Zion Canyon.