What is the Henry's Fork Caldera and how did it form?

The Henry's Fork Caldera is a large volcanic depression located in eastern Idaho's Island Park region, formed roughly 1.3 million years ago by the Yellowstone hotspot. Driven by the second major cycle of the region's volcanism, the massive eruption distributed at least 280 cubic kilometers of ash known as the Mesa Falls Tuff. Today, it is notable for being the only clearly visible caldera among the succession created by the Yellowstone hotspot.

What we know

• The Henry's Fork Caldera was formed 1.3 million years ago by an eruption of the Yellowstone hotspot, marking the culmination of the second major volcanic cycle. [2, 3]
• The eruption produced at least 280 cubic kilometers of ash, referred to as the Mesa Falls Tuff. [2, 3]
• The caldera measures 18 miles long and 23 miles wide and is nested inside the larger Island Park Caldera. [2]
• Among the many calderas formed by the Yellowstone hotspot, Henry's Fork is currently the only one clearly visible. [2]

Where to go next

• compared withWhat is the Island Park Caldera?
• what caused itHow does the Yellowstone hotspot drive regional volcanism?
• a case in pointWhat are the characteristics of the Mesa Falls Tuff?
• how it workedHow do volcanic calderas form through ground collapse?
• whereWhat wildlife and recreation can be found in Harriman State Park?
• an unexpected connectionHow is a volcanic collapse linked to sinkholes?Although calderas are massive volcanic features, they form through structural subsidence rather than explosions, making them a type of sinkhole.

Sources

• [1]Henry's Fork Caldera (Wikidata Q5716865) · CC0 1.0
• [2]Henry's Fork Caldera · CC BY-SA 4.0
• [3]Yellowstone Caldera · CC BY-SA 4.0
• [4]Henrys Fork (Snake River tributary) · CC BY-SA 4.0
• [5]Caldera · CC BY-SA 4.0