Aspen Butte is a steep-sided shield volcano

Shield volcano

A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes...

 in the Cascade Range

Cascade Range

The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades...

 of southern Oregon

Oregon

Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...

. It is located 15 miles (24 km) south of Pelican Butte

Pelican Butte

Pelican Butte is a steep-sided dormant shield volcano in the Cascade Range of southern Oregon. It is located due south of Crater Lake and northeast of Mount McLoughlin, and rises over directly above the shore of Upper Klamath Lake...

 and 15 miles (24 km) southeast of Mount McLoughlin

Mount McLoughlin

Mount McLoughlin is a steep-sided lava cone built on top of a shield volcano in the Cascade Range of southern Oregon and within the Sky Lakes Wilderness area. It is one of the volcanic peaks in the Cascade Volcanic Arc. The mountain is north of Mount Shasta, south of Crater Lake, and west of Upper...

. It rises over 4000 foot above the nearby shore of Upper Klamath Lake

Upper Klamath Lake

Upper Klamath Lake is a large, shallow freshwater lake east of the Cascade Range in south central Oregon in the United States. The largest freshwater body in Oregon, it is approximately 20 mi long and 8 mi wide and extends northwest from the city of Klamath Falls...

. Ice Age

Ice age

An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...

 glaciers carved three large cirques

Cirque (landform)

thumb|250 px|Two cirques with semi-permanent snowpatches in [[Abisko National Park]], [[Sweden]].A cirque or corrie is an amphitheatre-like valley head, formed at the head of a valley glacier by erosion...

 into the north and northeast flanks of the mountain removing most of the original summit area including any evidence of a crater. The summit is now the high point along the curving ridge which bounds the southern edge of the cirques above steep cliffs.

Aspen Butte is the highest of four overlapping shield volcanoes within the Mountain Lakes Wilderness

Mountain Lakes Wilderness

The Mountain Lakes Wilderness is a wilderness area located in the Fremont–Winema National Forests in the southern Cascade Range of Oregon, USA. It surrounds a cluster of four overlapping shield volcanoes, the highest of which is Aspen Butte...

 all of which have been carved to varying degrees by glaciers. The other volcanoes are 7979 feet (2,432 m) Mount Harriman,
7785 feet (2,373 m) Crater Mountain and 7741 feet (2,359 m) Greylock Mountain. Another peak, 7882 feet (2,402 m) Mount Carmine,
which lies just over 1 miles (1.6 km) to the north of Aspen Butte, is actually not a separate volcano but the highest remnant of the north flank of the Aspen Butte volcano separated from it by two glacial cirques. Little Aspen Butte, a 7235 feet (2,205 m) satellite cone

Satellite cone

A parasitic cone is the cone-shaped accumulation of volcanic material not part of the central vent of a volcano. One forms by eruptions from fractures on the flank of the volcano. These fractures occur because of the flank of the volcano is unstable...

, rises on the southern flanks of the main volcano separated from it by a 6556 feet (1,998 m) pass.