Volcanic super-eruptions associated with Yellowstone hotspot track announced

Representational Image: Reuters

New Delhi: Volcanic super-eruptions have been some of the most extreme events ever to affect Earth's surface. Although these explosions eject enormous volumes of material --at least 1,000 times more than the 1980 eruption of Mount St. Helens -- and have the potential to alter the planet's climate, few super-eruptions have been documented, according to ScienceDaily report.

In a study published in Geology, the discovery of two newly identified super-eruptions associated with the Yellowstone hotspot track has been announced by researchers. This is believed to be volcanic province's largest and most cataclysmic event, the report said. 

The research team reportedly used a combination of techniques, including bulk chemistry, magnetic data, and radio-isotopic dates, to correlate volcanic deposits scattered across tens of thousands of square kilometers. 

Thomas Knott, a volcanologist at the University of Leicester and the paper's lead author, is quoted as saying, "We discovered that deposits previously believed to belong to multiple, smaller eruptions were in fact colossal sheets of volcanic material from two previously unknown super-eruptions at about 9.0 and 8.7 million years ago." 

"The younger of the two, the Grey's Landing super-eruption, is now the largest recorded event of the entire Snake-River-Yellowstone volcanic province," Knott said, adding "It is one of the top five eruptions of all time." 

The team, including researchers from the British Geological Survey and the University of California, Santa Cruz, estimated that the Grey's Landing super-eruption was 30% larger than the previous record-holder (the well-known Huckleberry Ridge Tuff) and had devastating local and global effects, said the ScienceDaily report. 

Researchers estimated that both of the newly discovered super-eruptions occurred during the Miocene, the interval of geologic time spanning 23-5.3 million years ago. The report further explained that the recurrence rate of Yellowstone hotspot super-eruptions during the Miocene was, on average, once every 500,000 years.

The study, which has been built on decade-long contributions by many other researchers, grew out of a larger project that investigated the productivity of major continental volcanic provinces, the report added.