Oblique view looking east towards Phantom Ship and Danger
Bay. The distance across the bottom of the image is about 1.2
kilometers (0.7 miles).
Andesite lava from near the Phantom Ship is the oldest rock
found above the surface of the lake, and dates from about 400,000
years ago. Phantom Ship itself is composed of resistant, hydrothermally
altered andesite lava. The steep underwater cliffs below it owe
their survival to the same alteration system within and beneath
the ancient Phantom Ship volcano. Rocks forming the more deeply
submerged cliffs almost certainly pre-date the formation of Mount
Mazama, as do the rocks of the cliff below Sentinel Rock. Clearly
shown in the foreground of this view is the Chaski Bay landslide
deposit (A). In the middle distance is the Danger Bay slide.
Source: Gardner, James V., Peter Dartnell, Laurent Hellequin,
Charles R. Bacon, Larry A. Mayer, and J. Christopher Stone. 2001.
Bathymetry and selected perspective views of Crater Lake, Oregon.
USGS Water Resources Investigations Report 01-4046.
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