V. Geological and
Biological Information on Crater Lake Area
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E. Points of Geological Interest
in Crater Lake National Park
2. Wizard
Island
The next most striking object after the gigantic
carven cliffs is Wizard Island. This complete volcano in miniature,
notwithstanding that it is forest-clothed and rises from water, carries the
traveler's mind instantly to the thirteen similar cones which rise within the
enormous desert crater of dead Haleakala, in the Hawaii National Park. Wizard
Island's crater may easily be seen in the tip of its cone.
Rising 763 feet above the water, this island is an excellent example of the
smallest type of volcanic cone. It was formed by globs of cinders, ash, and
molten rock shot from the caldera floor, which, because, of their weight, fell
back immediately around the vent, producing its steep sides. The lower part of
the island is an extremely rough lava field, thinly forested, with eight species
of conifers, while the upper two-thirds is composed of cinders, ash, and broken
pumice loosely piled on the slopes.
The summit of this perfect little
cone is a crater about 90 feet deep and 300 feet in diameter. The cone and its
massive flow of black lava in huge blocks form an island about three-fourths of
a mile long by one-half mile wide. The low-lying part near the shore encloses a
small lake 40 feet deep. The oldest trees on the island date from about 800
years ago, indicating the last volcanic activity of Mount Mazama occurred about
1,000 years in the past. A variety of small mammals, including pika, chipmunks,
and golden-mantled ground squirrels, inhabit the island.
Illustration 2. Wizard Island,
1937. Courtesy Oregon Historical Society, Portland.
