List of large volume volcanic eruptions in the Basin and Range Province facts for kids

Giant Volcano Blasts in the Basin and Range Province

The Basin and Range Province is a huge area in the western United States. It stretches across states like Utah, California, Idaho, Colorado, New Mexico, Texas, Arizona, Nevada, Wyoming, and Oregon. This region has seen some truly massive volcanic eruptions, often called "super-eruptions." These powerful events also include eruptions from famous places like the Long Valley Caldera and the Yellowstone hotspot.

Volcano Hotspots

A volcanic field is a place where many volcanoes and volcanic vents are found together. The Basin and Range Province is home to several of these hotspots.

Some of the main volcanic fields in this region are:

• Northwestern Nevada
• The Modoc Plateau
• Central Nevada
• The Great Basin
• Southwestern Nevada
• The Mojave Desert
• The Long Valley Caldera area

Well-known volcanic fields include:

• Coso Volcanic Field
• Mono Lake Volcanic Field
• Marysvale Volcanic Field
• San Juan volcanic field
• Indian Peak
• Central Colorado volcanic field
• Jemez volcanic lineament
• Mogollon-Datil volcanic field
• Santa Rosa-Calico
• Boot Heel volcanic field

Land Features and Earth's Movements

Many land features in the Western United States point towards the northeast. This is the same direction that the North American craton (the old, stable core of the continent) is moving.

For example, you can see this direction in:

• The Trans-Challis fault zone in Idaho.
• The Snake River in Oregon.
• The Garlock Fault in California.
• The Colorado River in Utah.
• The Colorado Mineral Belt.
• The Crater Flat-Reveille Range-Lunar Crater line.
• The Northwestern Nevada volcanic field.
• The San Juan caldera cluster in Colorado.
• The Socorro-Magdalena caldera cluster in New Mexico.
• The Jemez Lineament.
• The Yellowstone hotspot trail.

However, the Yellowstone hotspot trail has been changed by faults (cracks in the Earth's crust) and extension (when the crust stretches and pulls apart).

How the Geology Changed

Before a time called the Eocene Epoch (about 56 to 34 million years ago), two of Earth's giant plates, the Farallon and North American Plates, were crashing into each other quickly. The Farallon Plate was sliding under the North American Plate at a shallow angle. This process is called subduction.

During the Eocene, the pushing forces from this plate collision stopped. This event was part of something called the Laramide orogeny, which built mountains. The way the plates interacted changed. Instead of pushing straight together, they began to slide past each other at an angle.

This change caused a huge increase in volcanic activity across the Basin and Range Province. Scientists think the Farallon Plate continued to slide underneath until about 19 million years ago. At that point, it was mostly gone, and some volcanic activity slowed down.

Around 17 million years ago, a type of rock called Olivine basalt erupted. This rock comes from deep inside the Earth. At the same time, the Earth's crust began to stretch and pull apart, a process called extension. This stretching created long, north-south cracks and valleys. Examples include the Great Basin, the Walker trough, the Owens graben (a sunken block of land), and the Rio Grande rift.

Major Eruptions in the Basin and Range Province

Here are some of the largest volcanic eruptions that have happened in the Basin and Range Province:

• Long Valley Caldera; California, USA; about 759,000 years ago; a massive VEI 7 eruption. It blasted out about 600 km³ (140 cu mi) of rock and ash, forming the Bishop Tuff.
• Valles Caldera, New Mexico, USA; around 1.15 million years ago; a VEI 7 eruption. It produced about 600 km³ (140 cu mi) of the Tshirege formation.
• Valles Caldera, New Mexico, USA; around 1.47 million years ago (Lower Bandelier eruption).
• Yellowstone hotspot (?), Lake Owyhee volcanic fields; 15.0 to 15.5 million years ago.
• Yellowstone hotspot (?), Northwest Nevada volcanic field; 15.5 to 16.5 million years ago. This included eruptions near the Pine Forest Range, Nevada, and produced tuffs like Idaho Canyon and Ashdown.
• Columbia River Basalt Province: The Yellowstone hotspot caused a huge burst of volcanic activity. The first eruptions were near the Oregon-Idaho-Washington border.
  • Columbia River flood basalts, about 175,000 km³ (42,000 cu mi) of lava.
  • Steens flood basalts, about 65,000 km³ (16,000 cu mi) of lava.
• Mount Belknap Caldera (17 km × 12 km (10.6 mi × 7.5 mi)), Marysvale Volcanic Field, Utah; 19 million years ago; about 150 km³ (36 cu mi) of ash and rock.
• Big John Caldera (10 km × 6 km (6.2 mi × 3.7 mi)), Marysvale Volcanic Field, Utah; 22 million years ago; about 50 km³ (12 cu mi) of Delano Peak Tuff.
• Monroe Peak Caldera (20 km × 16 km (12.4 mi × 9.9 mi)), Marysvale Volcanic Field, Utah; 23 million years ago; about 200 km³ (48 cu mi) of Osiris Tuff.
• Lake City calderas (20 km (12 mi) wide), San Juan volcanic field, Colorado; 23.1 million years ago; about 300 km³ (72 cu mi) of Sunshine Peak Tuff.
• Turkey Creek Caldera (25 km (16 mi) wide), Chiricahua National Monument, Arizona; 25 million years ago; about 500 km³ (120 cu mi) of Rhyolite Canyon Formation.
• Questa Caldera (15 km (9.3 mi) wide), Questa-Latir volcanic locus, New Mexico; 26 million years ago; about 400 km³ (96 cu mi) of Amalia Tuff.
• Creede Caldera (24 km (15 mi) wide), San Juan volcanic field, Colorado; 26.7 million years ago; less than 500 km³ (120 cu mi) of Snowshoe Mountain Tuff.
• La Garita Caldera (100 km × 35 km (62 mi × 22 mi)), San Juan volcanic field, Colorado; a massive VEI 8 eruption. More than 5,000 km³ (1,200 cu mi) of Fish Canyon Tuff was blasted out about 27.8 million years ago. This was one of the largest known eruptions on Earth.
• San Juan Caldera (22 km × 24 km (14 mi × 15 mi)), San Juan volcanic field, Colorado; 28 million years ago; more than 1,000 km³ (240 cu mi) of Sapinero Mesa Tuff.
• Uncompahgre Caldera (23 km × 20 km (14 mi × 12 mi)), San Juan volcanic field, Colorado; 28.1 million years ago; more than 1,000 km³ (240 cu mi) of Dillon/Sapinero Mesa Tuffs.
• Platoro calderas, San Juan volcanic field, Colorado; 28.2 million years ago; about 1,000 km³ (240 cu mi) of Chiquito Peak Tuff.
• Bachelor Caldera (20 km × 28 km (12 mi × 17 mi)), San Juan volcanic field, Colorado; 27.35 million years ago; about 1,200 km³ (290 cu mi) of Carpenter Ridge Tuff.

Rupelian Age Calderas

The Rupelian age was a time period from about 33.9 to 28.4 million years ago. Many large calderas formed during this time:

• Bursum Caldera (40 x 30 km), Mogollon-Datil volcanic field, New Mexico; 28.5 million years ago; produced 1,050 cubic kilometres (250 cu mi) of Bloodgood Canyon Tuff and 1,200 cubic kilometres (290 cu mi) of Apache Springs Tuff.
• San Juan Caldera (24 x 22 km), San Juan volcanic field, Colorado; 28.5 million years ago; about 900 cubic kilometres (220 cu mi) of ash and rock.
• Around White Rock caldera (50 km North-South), White Rock Mountains, Nevada; 29.02 million years ago; about 2,600 cubic kilometres (620 cu mi) of Lund Tuff.
• Indian Peak, Eastern Nevada; 29.5 million years ago; more than 3,200 cubic kilometers (768 cu mi) of Wah Wah Springs Tuff.
• William's Ridge, Central Nevada; 31.4 million years ago; about 3,500 cubic kilometres (840 cu mi) of Windous Butte Tuff.
• Chinati Caldera (30 x 20 km), Chinati Mountains, Texas; 32.5 million years ago; about 1,000 cubic kilometres (240 cu mi) of Mitchel Mesa Rhyolite.
• Emory Caldera (25 x 55 km), Mogollon-Datil volcanic field, New Mexico; 33 million years ago; a VEI 8 eruption that produced about 1,310 cubic kilometers (314 cu mi) of Kneeling Nun Tuff.
• Socorro Caldera (25 x 35 km), Rio Grande rift, New Mexico; 33 million years ago; about 500 cubic kilometres (120 cu mi) of Hells Mesa Rhyolite.
• Mount Princeton (eroded), Central Colorado volcanic field; 35.3 million years ago; more than 1,000 cubic kilometres (240 cu mi) of Wall Mountain Tuff.
• Davis Mountains, Texas; several large eruptions between 35.35 and 36.82 million years ago. One produced 1,250 cubic kilometres (300 cu mi) of Flood rhyolites and Gomez Tuff.
• Twin Peaks Caldera (20 km), Challis volcanic field, Idaho; 45 million years ago; about 500 cubic kilometres (120 cu mi) of Challis Creek Tuff.
• Tucson Mountain Caldera (25 km wide), Tucson Mountains, Arizona; 73 million years ago; about 500 cubic kilometres (120 cu mi) of Cat Mountain Tuff.

Sources

Columbia River Basalt Province-sources

• Web citations:

Peter W. Lipman – sources

Maps

• Overview map at Basin and Range Province.
• Map of the Basin and Range Province
• Map: Thelin and Pike (1991), Landforms of the conterminous United States – A digital shaded-relief portrayal, USGS Map I-2206
• Global Positioning System (GPS) Time Series
• Great Basin/Nevada

• • • Supplemental material: Columbia River Basalt Group, eruptive loci
• Great Basin/Utah

• Colorado

• New Mexico

• • Mogollon-Datil volcanic field

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