Crater Lake Volcano - John Seach

john

Oregon, USA

42.93  N 122.12  W
summit elevation 2487 m
Caldera

Crater Lake is located in the southern Cascade Range of Oregon. The lake is 8.9 km in diameter and 590 m deep. Wizzard Island is a post caldera cinder cone. The lake is located in Crater Lake National Park.

The chain of volcanoes of the High Cascades approximately parallels the plate boundary, and is related to subduction of the small Juan de Fuca and Gorda plates beneath the North American plate. Mount Mazama lies at the north end of the Klamath graben.

Many silicic domes and associated lava flows occur within 10 km of the eastern caldera wall of Crater Lake. Dacite and rhyodacite was erupted from at least 25 vents distributed over 120 sq km.

Eruption of Mount Mazama
Crater Lake was formed 5677 ± 150 B.C. when 50 cubic km of material was erupted from Mount Mazama. The climactic, caldera-forming eruption of Mount Mazama can be divided into two phases: single vent and ring vent. Onset of collapse of the caldera probably caused the switch from the first to the second phase of eruption.

Crater Lake Volcano Eruptions

7627 ± 150 years ago.