Belknap Crater is a 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...

 in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of 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...

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Belknap volcano is a Holocene

Holocene

The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

 example of the process which built the High Cascade Platform during the Pleistocene

Pleistocene

The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

. It is a small shield volcano with a capping cinder cone

Cinder cone

According to the , Cinder Cone is the proper name of 1 cinder cone in Canada and 7 cinder cones in the United States:In Canada: Cinder Cone In the United States:...

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A number of other eruptions also occurred in the general area during roughly the same time period. About 1,300 years ago (1,330 ¹⁴C years

Radiocarbon dating

Radiocarbon dating is a radiometric dating method that uses the naturally occurring radioisotope carbon-14 to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Raw, i.e. uncalibrated, radiocarbon ages are usually reported in radiocarbon years "Before Present" ,...

 B.P.) a series of small spatter cones formed between Belknap and Blue Lake. North of these, a phreatic

Phreatic

The term phreatic is used in Earth sciences to refer to matters relating to ground water below the water table . The term 'phreatic surface' indicates the location where the pore water pressure is under atmospheric conditions...

 explosion blasted out the crater which is today occupied by Blue Lake. To the south are several cinder cones and associated lava flows, including Collier, Four-in-One, and Yapoah cones. Four-in-One Cone has been dated at about 1,900 years old (1,980 ¹⁴C years B.P.) while Collier is dated at about 1,500 years old (1,600 ¹⁴C years B.P.)

Notable vents

Name	Elevation	Coordinates	Last eruption
Blue Lake	-	-	-
Spatter Cone Chain	-	-	-
Belknap Crater	-	-	-
Little Belknap	-	-	-
South Belknap Cone	-	-	-
Yapoah Cone	-	-	-
Four-in-One Cone	-	-	~1,900 years ago
Collier Cone	-	-	~1,500 years ago