When you purchase through links on our site , we may pull in an affiliate commission . Here ’s how it work .
Up to 12 massive volcanic blast occur between 8 million and 12 million years ago in Idaho ’s Snake River Plain , lead up to today ’s Yellowstone supervolcano , new research break .
A dozen of theseancient supereruptionstook position along the Yellowstone hotspot cartroad , researchers reported Feb. 10 in the journalGeological Society of America Bulletin . The trail of eruptions marks where the North American architectonic plate sailed over a superhot blob of mantle rock called a hotspot . ( The drapery is the rocky layer between Earth ’s crust and burden . )
A deep canyon in southern Idaho exposes volcanic deposits left behind by several different eruptions.
Though learning of more supereruptions in the West may seem unsettling , the findings do not suggest that Yellowstone today is any more hazardous than antecedently surmise . Instead , the research worker articulate they are now studying whether Yellowstone is in reality dwindle away in strength compared to the large and more violent clap that occurred 12 million years ago . [ See photos of how researchers studied the Snake River Plain ’s ancient supereruptions ]
" While it is well - known that Yellowstone has erupted catastrophically in recent times , perhaps less wide appreciated is that these were just the up-to-the-minute in a prolonged history of numerous ruinous supereruptions that have burned a track along the Snake River eastwards from Oregon to Yellowstone , " lead study source Tom Knott , a geochemist at the University of Leicester in the United Kingdom , said in a command .
The rainbow - colorise raging leap andhigh - fell geysersat Yellowstone National Park in Wyoming are fed by an underground source of molten rock candy . The park mold in a series of eruption during the past 2 million class . knock-down explosions 640,000 years ago created a giant crater and spew out ash as far as New York . The most late eruption come about 70,000 class ago .
Until now , geologists did not have a firm count of the identification number of eruptions in Idaho and surrounding states that antedate Yellowstone , nor a good estimation of the sizing of each flare-up . The new sketch suggests there are fewer volcanic eruptions in the central Snake River Plain than previously believe . However , the 12 recorded giant eruptions were likely " significantly larger " than other study suggested , the researcher enounce .
The craters formed by these jumbo eruptions are now buried under sediment and younger lava flows . To better read past eruptions , Knott led an international team of vent experts in analyze the many layers of lava plating central Idaho . The researcher fingerprinted dissimilar bam by try for changes in the chemical war paint of the rocks and the rock music ' magnetic orientation . ( Every volcanic eructation give rise lava with a unique chemical substance make-up . ) The squad correlated these volcanic deposits across hundreds of mi ( thousand of kilometers ) .
With the new correlativity , the squad reduced the telephone number of eruption mean to have originated from the central Snake River Plain by more than one-half . The research also revealed that these irruption were significantly larger than suspected , and may have touch those at Yellowstone . [ Countdown : History ’s Most Destructive Volcanoes ]
Hotspots seem to ride out in one spot while the Earth ’s crust trundles over them . The crustal movement create a line of volcanoes , like the crumb allow for behind by a fairy story Hansel and Gretel . The Hawaiian island and Emperor Seamounts are textbook examples ofhotspot volcanism .
One of the supereruptions from the Yellowstone hot spot track , called the Castleford Crossing eruption , now cover an surface area more than 5,400 square international nautical mile ( 14,000 square km ) in southern Idaho , and is more than 4,200 metrical foot ( 1.3 klick ) deep in the caldera of the Castleford Crossing supervolcano . The eruption was likely 10 times as herculean as Mount St. Helens ' 1980 blast , the study account .
" The size and magnitude of this newly defined eruption is as large as , if not large than well - known eruptions at Yellowstone , and it is just the first in an emerging record of newly discovered supereruptions during a full stop of intense magmatic activity between 8 [ million ] and 12 million years ago , " Knott say .
