Crater Lake Volcano
Updated: Mar 20, 2025 01:03 GMT -
caldera
Oregon (Canada and USA (mainland)), 42.93°N / -122.12°W 
Summit height: 2487 m / 8,159 feet
Current status: normal or dormant (1 out of 5)
Crater Lake in the southern Cascade Range of Oregon, USA, is one of the most beautiful calderas in the world. It formed by the collapse of a massive stratovolcano known as Mount Mazama about 6850 years ago. The caldera measures 8x10 km in diameter and is filled with a lake of up to 600 m depth.
A small island, Wizzard Island, is a cinder cone that grew after the formation of the caldera. The caldera is part of Crater Lake National Park.
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Crater Lake volcano eruptions: 2850 BC (?), 7627±150 years ago
Latest nearby earthquakes
| Date and Time | Mag / Depth | Distance / Location | |||
|---|---|---|---|---|---|
Background
Prior to the formation of the caldera, Mount Mazama was a complex of overlapping shield and stratovolcanoes. It is located at the north end of the Klamath graben on the main N-S trending axis of the Cascades volcanoes.The earliest stage of volcanism of Mazama volcano constructed at least five andesitic and dacitic shields and stratovolcanoes between about 420-40,000 years ago. A second phase of activity took place between 30,000 years ago and the caldera-forming eruption, building rhyodacitic lava domes and flows and associated pyroclastic rocks.
Caldera-forming eruption of Mount Mazama
The explosive eruptions (dated 5677 BC ± 150 years) triggering the collapse of the caldera was one of Earth's largest known eruptions in the past 10,000 years. It erupted about 50 cubic km3 of magma and ranks as VEI=7. Ash from the eruption was deposited as far as Canada and producing pyroclastic flows traveled 40 km from the volcano.
The deep blue lake is North America's second deepest lake, masuring almost 600 m. It fills the caldera to within 150-600 m of its rim.
Post-caldera eruptions took place within a few hundred years of caldera formation and constructed a series of small lava domes on the caldera floor, forming Wizard Island cinder cone, and the completely submerged Merriam Cone.
The latest eruptions produced a small rhyodacitic lava dome beneath the lake surface east of Wizard Island about 4200 years ago.
Crater Lake Volcano Photos
Clear view onto the lava lake inside Marum's west crater. (Photo: Tom Pfeiffer)
The green Okama crater lake of Zao volcano, NE Honshu, Japan (Photo: Tom Pfeiffer)
Erta Ale volcano's lava lake back in Nov 2009.
The red glow of the lava illuminates the crater walls under the blue sky of dusk. A small group of observers is on ...
The red glow of the lava illuminates the crater walls under the blue sky of dusk. A small group of observers is on ...
Lava lake inside Kilauea volcano's West Gap crater. The whole crust covering the lake has just been overturned, exposing the red hot glowing interior. hawaii_e7837 (Photo...
Significant volcanic eruptions: Crater Lake volcano
No historic eruptions are known from Crater Lake volcano, but evidence from at least 5 eruptions during the past 10,000 years can be found in the geological record.
The table below lists all known eruptions (date in bold face) of Crater Lake volcano in historic times and during the past 10,000 years. Updates on the most recent volcanic activity of Crater Lake can be found on the news page of Crater Lake volcano.
| Date | Note | VEI | Deaths | Damage | |
|---|---|---|---|---|---|
| Lava dome ENE of Wizard Island | ? | ||||
| Wizard Island and Merriam Cone | ? | ||||
| Central Platform | ? | ||||
| Mt. Mazama summit and flank vents | 7 | ||||
| North flank (Llao Rock) | 6 | ||||
Remark:
Our list of volcanic eruptions closely follows the database of eruptions of the Smithsonian's Global Volcanism Project (GVP), the internationally most recognized data source for volcanic eruptions, but also includes significant eruptive episodes or related volcano events. "Volcanic eruptions" are usually to be understood as sequences of individual eruptive episodes that can follow each other, or even overlap (if several vents are involved), and can last many years, decades or even longer. For example, the current activity of Stromboli volcano is understood as a single eruption that has been ongoing since 1934.
Sources: NOAA National Centers for Environmental Information (NCEI), Global Significant Volcanic Eruptions Database. doi:10.7289/V5TD9V7K | Global Volcanism Project / Smithsonian Institution
Crater Lake Volcano FAQ
+When was the last eruption of Crater Lake volcano?
The last confirmed eruption of Crater Lake occurred in 2850 BC.
+When was the largest eruption of Crater Lake volcano?
The largest eruption known from the younger geological history of Crater Lake volcano occurred around 5680 BC. It only has a VEI (Volcanic Explosivity Index) of , likely because it was a mainly effusive eruption generating lava flows but very little ash.
Latest satellite images
Crater Lake Volcano Maps
Below is a selection of maps showing the location and surroundings of the volcano at various resolutions based on aerial-imagery / terrain maps. Feel free to use them for non-commercial purposes on your blog or website as long as you credit them with a link back to this page (click to copy it).
Satellite/aerial-type map of Crater Lake volcano (world scale)
Terrain-type map of Crater Lake volcano (world scale)
Satellite/aerial-type map of Crater Lake volcano (region scale large)
Terrain-type map of Crater Lake volcano (region scale large)
Satellite/aerial-type map of Crater Lake volcano (region scale medium)
Terrain-type map of Crater Lake volcano (region scale medium)
Satellite/aerial-type map of Crater Lake volcano (region scale small)
Terrain-type map of Crater Lake volcano (region scale small)
Satellite/aerial-type map of Crater Lake volcano (local scale large)
Terrain-type map of Crater Lake volcano (local scale large)
Satellite/aerial-type map of Crater Lake volcano (local scale medium)
Terrain-type map of Crater Lake volcano (local scale medium)
Satellite/aerial-type map of Crater Lake volcano (local scale small)
Terrain-type map of Crater Lake volcano (local scale small)
Satellite/aerial-type map of Crater Lake volcano (scale of 10s of km)
Terrain-type map of Crater Lake volcano (scale of 10s of km)
Satellite/aerial-type map of Crater Lake volcano (scale of 20-40 km)
Terrain-type map of Crater Lake volcano (scale of 20-40 km)
Satellite/aerial-type map of Crater Lake volcano (scale of approx. 10-20 km)
Terrain-type map of Crater Lake volcano (scale of approx. 10-20 km)
Satellite/aerial-type map of Crater Lake volcano (scale of 5-10 km)
Satellite/aerial-type map of Crater Lake volcano (scale of few kilometers)
