How big is the magma chamber under Yellowstone?
Yellowstone is underlain by two magma bodies. The shallower one is composed of rhyolite (a high-silica rock type) and stretches from 5 km to about 17 km (3 to 10 mi) beneath the surface and is about 90 km (55 mi) long and about 40 km (25 mi) wide. The chamber is mostly solid, with only about 5-15% melt. The deeper reservoir is composed of basalt (a low-silica rock type) and extends from 20 to 50 km (12 to 30 mi) beneath the surface. Even though the deeper chamber is about 4.5 times larger than the shallow chamber, it contains only about 2% melt.
The method that scientists use to discern this information is similar to medical CT scans that bounce X-rays through the human body to make three-dimensional pictures of internal tissue. In an analogous manner, a method called seismic tomography uses hundreds to thousands of earthquakes recorded by dozens of stations to measure the speed of seismic waves through the Earth--data that allow geophysicists to make three-dimensional pictures of structures beneath the surface. Scientists compare these seismic velocities and infer the composition by comparing them with average, thermally undisturbed values.
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Geologic field-trip guide to the volcanic and hydrothermal landscape of the Yellowstone Plateau
Yellowstone National Park, a nearly 9,000 km2 (~3,468 mi2) area, was preserved in 1872 as the world’s first national park for its unique, extraordinary, and magnificent natural features. Rimmed by a crescent of older mountainous terrain, Yellowstone National Park has at its core the Quaternary Yellowstone Plateau, an undulating landscape...
Morgan Morzel, Lisa Ann; Shanks, W. C. Pat; Lowenstern, Jacob B.; Farrell, Jamie M.; Robinson, Joel E.
Steam explosions, earthquakes, and volcanic eruptions -- what's in Yellowstone's future?
Yellowstone, one of the world’s largest active volcanic systems, has produced several giant volcanic eruptions in the past few million years, as well as many smaller eruptions and steam explosions. Although no eruptions of lava or volcanic ash have occurred for many thousands of years, future eruptions are likely. In the next few hundred years,...
Lowenstern, Jacob B.; Christiansen, Robert L.; Smith, Robert B.; Morgan, Lisa A.; Heasler, Henry
Tracking changes in Yellowstone's restless volcanic system
No abstract available.
Stauffer, Peter H.
The Quaternary and Pliocene Yellowstone Plateau volcanic field of Wyoming, Idaho, and Montana
This region of Yellowstone National Park has been the active focus of one of the Earth's largest magmatic systems for more than 2 million years. The resulting volcanism has been characterized by the eruption of voluminous rhyolites and subordinate basalts but virtually no lavas of intermediate composition. The magmatic system at depth remains...
Christiansen, Robert L.
Inside USGS, No. 6, Ken Pierce, Heavy Breathing of Yellowstone Caldera
Dr. Kenneth Pierce studied the geology and geomorphology of the greater Yellowstone area for nearly his entire career with the U.S. Geological Survey. From 1965 to present, Dr. Pierce has mapped glacial deposits, pioneered Quaternary dating techniques, conducted research on the Yellowstone Hot Spot, studied the geothermal areas, explored the geology of archaeological sites
The Yellowstone Volcano: Past, Present and Future
Public Lecture on Yellowstone Volcano by Jake Lowenstern at Menlo Park, CA on January 23, 2014. The Q&A at the end of the talk can be found on the original source video (Source URL).
Caldera Demonstration Model
A caldera is a large, usually circular volcanic depression formed when magma is withdrawn or erupted from a shallow underground magma reservoir. It is often difficult to visualize how calderas form. This simple experiment using flour, a balloon, tubing, and a bicycle pump, provides a helpful visualization for caldera formation.
Yellowstone Volcano Observatory (Part 2 of 3)
USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers
the following questions to provide a tour of the Yellowstone Volcano Observatory: "What is YVO?", "How
do you monitor volcanic activity at Yellowstone?", "How are satellites used to study deformation?", "Do
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Yellowstone Eruptions (Part 3 of 3)
USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers
the following questions to explain volcanic eruptions at Yellowstone: When was the last supereruption at
Yellowstone?", "Have any eruptions occurred since the last supereruption?", "Is Yellowstone overdue for
an eruption?", "What does the magma below indicate about a
Yes! Yellowstone is a Volcano (Part 1 of 3)
USGS Scientist-in-Charge of Yellowstone Volcano Observatory, Jake Lowenstern, answers
the following questions to explain volcanic features at Yellowstone: "How do we know Yellowstone is a
volcano?", "What is a Supervolcano?", "What is a Caldera?","Why are there geysers at Yellowstone?",
and "What are the other geologic hazards in Yellowstone?"
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