Yellowstone Caldera - Supervolcano

The Yellowstone Caldera is a volcanic caldera and supervolcano in Yellowstone National Park in the Western United States, sometimes referred to as the Yellowstone Supervolcano. The caldera and most of the park are located in the northwest corner of Wyoming. The major features of the caldera measure about 34 by 45 miles (55 by 72 km).

The caldera formed during the last of three supereruptions over the past 2.1 million years. Volcanic and tectonic actions in the region cause between 1,000 and 2,000 measurable earthquakes annually. Most are relatively minor, measuring a magnitude of 3 or weaker. Occasionally, numerous earthquakes are detected in a relatively short period of time, an event known as an earthquake swarm.

The last full-scale eruption happened approximately 640,000 years ago, ejecting approximately 240 cubic miles of rock, dust and volcanic ash into the sky. Geologists are closely monitoring the rise and fall of the Yellowstone Plateau, which has been rising as fast as 0.6 inches (1.5 cm) per year, as an indication of changes in magma chamber pressure. The upward movement of the Yellowstone caldera floor between 2004 and 2008 was almost 3 inches (7.6 cm) each year more than three times greater than ever observed since such measurements began in 1923. Read more...

In the News ...

Heat from below Pacific Ocean fuels Yellowstone, study finds   Science Daily - December 20, 2017
Recent stories in the national media are magnifying fears of a catastrophic eruption of the Yellowstone volcanic area, but scientists remain uncertain about the likelihood of such an event. To better understand the region's subsurface geology, geologists have rewound and played back a portion of its geologic history, finding that Yellowstone volcanism is more far more complex and dynamic than previously thought.

Yellowstone spawned twin super-eruptions that altered global climate   PhysOrg - October 26, 2017
A new geological record of the Yellowstone supervolcano's last catastrophic eruption is rewriting the story of what happened 630,000 years ago and how it affected Earth's climate. This eruption formed the vast Yellowstone caldera observed today, the second largest on Earth. Two layers of volcanic ash bearing the unique chemical fingerprint of Yellowstone's most recent super-eruption have been found in seafloor sediments in the Santa Barbara Basin, off the coast of Southern California. These layers of ash, or tephra, are sandwiched among sediments that contain a remarkably detailed record of ocean and climate change. Together, both the ash and sediments reveal that the last eruption was not a single event, but two closely spaced eruptions that tapped the brakes on a natural global-warming trend that eventually led the planet out of a major ice age.

  Build-up to an eruption at Yellowstone supervolcano that will plunge Earth into darkness could take just decades   Daily Mail - October 11, 2017

While the supervolcano hasn't erupted for 631,000 years, scientists have been working to understand what caused the last eruption. Their findings suggest that the forces that lead to an eruption move much more rapidly than previously believed. They claim new magma moves beneath Yellowstone only decades before a devastating eruption. Previous estimates suggested that the geological process that leads to such an event takes millenniums to occur. The researchers hope their findings will help to spot future supereruptions in the making.

Yellowstone has now been hit by a record breaking 'megaswarm' of 1,200 earthquakes in just a month   Daily Mail - July 21, 2017
In the most recent update on the ongoing earthquake storm, which scientists have been monitoring since June 12, the researchers say there have been 1,284 events so far, with the largest being a magnitude 4.4. While the activity has spurred fears that the supervolcano could be gearing up to an eruption, the experts say the risk of such an event is low, and the alert level remains at ‘normal.’

Scientists isolate, culture elusive Yellowstone microbe   PhysOrg - July 5, 2016

A microbial partnership thriving in an acidic hot spring in Yellowstone National Park has surrendered some of its lifestyle secrets to researchers. The team isolated the archaeon Nanopusillus acidilobi, cultured - tiny microbes - just 100 to 300 billionths of a meter in size - and can now study how they interact with their host, another archaeon (Acidilobus). The relationships between these two organisms can serve as a valuable model to study the evolution and mechanisms of more complex systems.

Milky Way over Yellowstone   NASA - August 27, 2014

The Milky Way was not created by an evaporating lake. The colorful pool of water, about 10 meters across, is known as Silex Spring and is located in Yellowstone National Park in Wyoming, USA. Illuminated artificially, the colors are caused by layers of bacteria that grow in the hot spring. Steam rises off the spring, heated by a magma chamber deep underneath known as the Yellowstone hotspot. Unrelated and far in the distance, the central band of our Milky Way Galaxy arches high overhead, a band lit by billions of stars. The above picture is a 16-image panorama taken late last month. If the Yellowstone hotspot causes another supervolcanic eruption as it did 640,000 years ago, a large part of North America would be affected.

Road Melts from Yellowstone Volcano's Heat   Live Science - July 12, 2014

Yellowstone National Park closed a popular road Thursday (July 10) after geothermal heat cooked the asphalt. Part of Firehole Lake Drive, a scenic one-way road off of Yellowstone's main loop, was shut down for repairs when oil bubbled to the surface, damaging the blacktop, the Park Service said in a statement. The closure doesn't affect the Grand Loop Road, which sees 20,000 visitors per day during the summer. Park spokesman Dan Hottle told Live Science that Firehole Lake Drive's surface hit 160 degrees Fahrenheit (70 degrees Celsius) on Thursday, about 30 degrees to 40 degrees F (17 to 22 degrees C) hotter than usual.

Earthquake Shakes Yellowstone But No Volcano Threat Looms, Scientists Say   Live Science - March 31, 2014

An earthquake of magnitude 4.8 shook Yellowstone National Park early Sunday (March 30). The tremor was the largest to hit the famed reserve in 34 years, but that doesn't mean Yellowstone's sleeping supervolcano is getting ready to spew, or even belch, scientists say. The epicenter of the quake was located 4 miles (6.4 kilometers) north-northeast of Norris Geyser Basin in the northwest corner of Wyoming. The tremor struck at 6:34 a.m. local time and was followed by at least 25 aftershocks in less than two hours, with the largest of magnitude 3.1, according to the U.S. Geological Survey.

Earthquake Rattles Yellowstone National Park, No Damage Reported   NBC - March 30, 2014
A 4.8 magnitude earthquake rocked Yellowstone National Park in Montana early today, but there were no immediate reports of damage.

Ancient Helium Escaping from Yellowstone   Live Science - February 19, 2014

The giant magma blob beneath Yellowstone National Park unleashed tons of ancient helium gas when it torched North America, according to a new study. "The amount of crustal helium coming out is way more than anyone would have expected," said Jacob Lowenstern, lead study author and scientist-in-charge at the U.S. Geological Survey's Yellowstone Volcano Observatory. Yellowstone National Park's famous geysers burble within the remains of a supervolcano that first exploded 2.1 million years ago. Both the volcano and the geysers owe their existence to a hotspot, a massive plume of molten rock rising from within Earth's mantle toward the surface.

Yellowstone's Volcano Bigger Than Thought   Live Science - April 17, 2013

Yellowstone's underground volcanic plumbing is bigger and better connected than scientists thought, researchers reported here today (April 17) at the Seismological Society of America's annual meeting. "We are getting a much better understanding of the volcanic system of Yellowstone," said Jamie Farrell, a seismology graduate student at the University of Utah. "The magma reservoir is at least 50 percent larger than previously imaged." Knowing the volume of molten magma beneath Yellowstone is important for estimating the size of future eruptions, Farrell told OurAmazingPlanet.

Yellowstone supervolcano fed by bigger plume   BBC - April 14, 2011
The underground volcanic plume at Yellowstone in the US may be bigger than previously thought, according to a new study by geologists. The volcanic hotspot below Yellowstone feeds the hot springs, mud pots and geysers that bring millions of visitors to the US national park each year. But the Yellowstone "supervolcano" has erupted violently in the distant past and could do so again at some point.

Electric Yellowstone: Conductivity image hints volcano plume is bigger than thought   PhysOrg - April 11, 2011

University of Utah geophysicists made the first large-scale picture of the electrical conductivity of the gigantic underground plume of hot and partly molten rock that feeds the Yellowstone supervolcano. The image suggests the plume is even bigger than it appears in earlier images made with earthquake waves.

Yellowstone Microbes Hint at Earth's Early Life   Live Science - March 1, 2010

In Glacier National Park, one can find rocks that are layered like cabbage leaves. These "stromatolites" are the work of microbes that lived more than a billion years ago. Stromatolites consist of multiple rock layers (or "stone blankets," as the Greek name implies) that formed in shallow, intertidal and sub-tidal environments. Most, if not all, of these rock formations are the remnants of ancient microbial mats that grew on top of each other in successive generations. Because stromatolites are found in the geologic record as far back 3.5 billion years ago, scientists would like to know exactly who lived in these microbial "high-rise buildings." The answer may be literally just down the road.