Oblique view looking northwest toward Wizard Island. The
distance across the bottom of the image is about 1.5 kilometers
(0.9 miles).
The cinder cone atop Wizard Island (which was named for its
resemblance to a wizard`s hat) is composed of small fragments
of frothy andesite. Blocky andesite lava flows emanate from the
base of the cinder cone. Sinuous channels in the drowned lava
field are depressions between lava flow lobes. The Wizard Island
volcano rose from the floor of the caldera while Crater Lake
was filling and ceased erupting before the lake reached its present
level. As flowing lava reached the water`s edge, it shattered
into melon-sized and smaller pieces that make up the slope below
the old shoreline (S3) located 84 meters (262 feet) below the
surface of the lake. An earlier shoreline (S2) at a depth of
180 meters (590 feet) can be seen partway down the east flank
of the volcano, perhaps representing a pause in the series of
eruptions that formed Wizard Island. At Skell Channel, lava flows
from the Wizard Island volcano abut the caldera wall. These flows
have been partially buried by loose rock falling from the talus
below The Watchman and Hillman Peaks. At the right edge of this
view is the younger rhyodacite dome.
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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