Medicine Lake Volcano is a large 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 northeastern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

  about 50 kilometres (31.1 mi) northeast of Mount Shasta

Mount Shasta

Mount Shasta is located at the southern end of the Cascade Range in Siskiyou County, California and at is the second highest peak in the Cascades and the fifth highest in California...

. The volcano

Volcano

2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...

 is located in a zone of east-west crustal extension east of the main axis of the Cascade Volcanic Arc

Cascade Volcanoes

The Cascade Volcanoes are a number of volcanoes in a volcanic arc in western North America, extending from southwestern British Columbia through Washington and Oregon to Northern California, a distance of well over 700 mi ...

 and 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...

. The 1 kilometre (0.621372736649807 mi) thick shield is 35 kilometres (22 mi) from east to west and 45 to 50 km (28 to 31.1 mi) from north to south, and covers more than 2000 square kilometres (772.2 sq mi).