GEOLOGY

Detailed explanation-1: -Having a maximum depth of 594 m (1, 949 ft), Crater Lake is the deepest lake in the United States. Mount Mazama straddles the Cascade volcanic axis and is a cluster of overlapping stratovolcanoes that is the most voluminous Quaternary volcanic system in the Oregon Cascades.

Detailed explanation-2: -Stratovolcanoes, also called composite volcanoes, tend to have a steep-sided conical form and highly explosive eruptions. Earlier eruptions built Mount Scott, which lies east of Crater Lake. As time continued, volcanoes began growing to the west building as layers of lava flows and pyroclastic deposits.

Detailed explanation-3: -A caldera (/kɔːlˈdɛrə, kæl-/ kawl-DERR-ə, kal-) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is gone.

Detailed explanation-4: -Geological Summary The spectacular 8 x 10 km Crater Lake caldera in the southern Cascades of Oregon formed about 7, 700 years ago as a result of the collapse of a complex of overlapping shield and stratovolcanoes known as Mount Mazama.

Detailed explanation-5: -Mount Defiance (about 500, 000 years old) on the south side of the Columbia River gorge and Lost Lake Butte northwest of Mount Hood are two examples of shield volcanoes.