Historic Resource Study, Crater Lake National Park, Oregon, 1984
V. Geological and Biological Information on Crater Lake Area
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.