Each cycle involved a large ignimbrite eruption, continental-scale ash-fall, and caldera collapse, preceded and followed by smaller lava flows and tuffs.

The 2005 docudrama Supervolcano, produced by the BBC and the Discovery Channel, increased public attention on the potential for a future catastrophic eruption.

The Yellowstone Plateau Volcanic Field lies at the eastern end of the Snake River Plain and disrupts the continuity of the Laramide orogenic belt, which formed during the Late Cretaceous.

[13] A proposed lower-mantle origin suggests a fragment of the subducting Farallon slab penetrated the 660 km (410 mi) discontinuity, pushing up the lower mantle and triggering melting of water-rich transition zone beneath the western United States.

[16] In this model, the North American Plate moves southwest at about 2.2 cm (0.87 in) per year over the relatively stationary plume, creating the observed age-progression of eruptive centers.

[19] A fault along the Snake River and Glade Creek, bounding the northern end of Teton Range and Huckleberry Ridge, is also thought to be part of the Island Park ring-fault.

More recent field mappings suggest the eastern ring-fault lies west of Sour Creek dome, closely following the Yellowstone River.

It is widely distributed and has been identified in the Pacific Ocean at Deep Sea Drilling Project Site 36, about 1,600 km (990 mi) from Island Park Caldera,[47] as well as in the Humboldt and Ventura basins of coastal California,[48] near Afton in Iowa, Benson in Arizona, and Campo Grande Mountain in Texas.

The Sheridan Reservoir Rhyolite, dated at 2.07±0.19 million years,[50] if vented from the Island Park ring-fracture, required a flow distance of at least 20 km (12 mi).

[51] Tiffany A. Rivera et al. (2017) suggest these two eruptions should not be assigned to the second cycle but instead represent the separate Lyle Spring magmatic system.

[55] The next pre-collapse rhyolite eruption is the Green Canyon Flow in the north of Big Bend Ridge, with a mapped volume of about 5 km3 (1.2 cu mi), dated at 1.2989±0.0009 million years.

[51] The Mesa Falls ash bed (formerly "Pearlette type S") is the distal ash-fall of this eruption, found in Brainard and Hartington in Nebraska, and in the southern Rocky Mountains of Colorado.

[56] While its age is indistinguishable from the Mesa Falls Tuff, field evidence indicates it formed after the collapse of the Henry's Fork Caldera.

[67] The Lewis Canyon Rhyolite group contains lavas dated to 0.8263±0.0184 million years,[67] though Robert L. Christiansen suggests they could be late-stage first-cycle eruptions.

[74] An explosive eruption deposited pumiceous fallout near Harlequin Lake,[65] which is immediately overlain by the Mount Haynes lava (0.7016±0.0014 million years).

[73] The climatic ash-flow eruption of the third cycle was the Lava Creek Tuff, dated at 0.6260±0.0026 million years,[34] during a glacial–interglacial transition in the Marine Isotope Stage.

[76] This composite tuff sheet consists of at least two members, distinguishable by a widely occurring welding intensity decrease between them,[77] and represents a total ash-flow volume of about 1,000 km3 (240 cu mi).

[84] Rather than having the simple structure of just two ignimbrite sheets, the Lava Creek Tuff may consist of multiple ash-flow lobes from distinct magma bodies.

[91] The Canyon lava flows of the Upper Basin Member erupted immediately after the Tuff of Sulphur Creek, as the ash-flow was still hot at the time of emplacement.

An explosion 13,800 years ago left a 5 km (3.1 mi) diameter crater at Mary Bay on the edge of Yellowstone Lake (located in the center of the caldera).

[103] Currently, volcanic activity is exhibited via numerous geothermal vents scattered throughout the region, including the famous Old Faithful Geyser, plus recorded ground-swelling indicating ongoing inflation of the underlying magma chamber.

[105][106] In December 2008, continuing into January 2009, more than 500 earthquakes were detected under the northwest end of Yellowstone Lake over a seven-day span, with the largest registering a magnitude of 3.9.

[111] The Lava Creek eruption of the Yellowstone Caldera, which occurred 640,000 years ago,[112] ejected approximately 1,000 cubic kilometres (240 cu mi) of rock, dust and volcanic ash into the atmosphere.

Geologists closely monitor the elevation of the Yellowstone Plateau, which has been rising as quickly as 150 millimetres (5.9 in) per year, as an indirect measurement of changes in magma chamber pressure.

This conclusion was reiterated in December 2013 in the aftermath of the publication of a study by University of Utah scientists finding that the "size of the magma body beneath Yellowstone is significantly larger than had been thought".

[122] A study published in GSA Today, the monthly news and science magazine of the Geological Society of America, identified three fault zones where future eruptions are most likely to be centered.

An analysis of crystals from Yellowstone's lava showed that prior to the last supereruption, the magma chamber underwent a rapid increase in temperature and change in composition.

The analysis indicated that Yellowstone's magma reservoir can reach eruptive capacity and trigger a super-eruption within just decades, not centuries as volcanologists had originally thought.

[citation needed] Over 20 large craters have been produced in the past 14,000 years, resulting in such features as Mary Bay, Turbid Lake, and Indian Pond, which was created in an eruption about 1300 BC.

[citation needed] In a 2003 report, USGS researchers proposed that an earthquake may have displaced more than 77 million cubic feet (2,200,000 m3; 580,000,000 US gal) of water in Yellowstone Lake, creating colossal waves that unsealed a capped geothermal system and led to the hydrothermal explosion that formed Mary Bay.