A Meteor Influence Could Have Precipitated a Large Landslide within the Grand Canyon

Researchers have lengthy puzzled over the presence of driftwood and lake sediments in Stanton’s Cave within the japanese Grand Canyon, whose mouth sits 150 ft (45.7 meters) above the river. How might the fabric presumably have reached that top? In keeping with Karl Karlstrom, a geologist from the College of New Mexico, it will have needed to be carried by flood ranges ten occasions larger than any seen up to now a number of thousand years.

A global group of researchers proposes a shocking chain of occasions because the perpetrator behind this thriller. They counsel that round 56,000 years in the past, the meteorite affect that created Arizona’s Meteor Crater triggered a landslide giant sufficient to dam the Colorado River and create a (now bygone) lake virtually 300 ft (91.4 m) deep, which might have allowed the driftwood and lake sediments to drift into the cave.

“Two iconic options of southwestern USA geology are linked by our speculation that the Barringer Meteorite Crater (Meteor Crater) affect in northern Arizona triggered cliff collapse in Grand Canyon 56,000 years in the past that dammed the Colorado River,” the researchers, co-led by Karlstrom, wrote in a examine revealed Tuesday within the journal Geology.

Scientists first came across the mysterious driftwood in Stanton’s Collapse 1970, when but unrefined radiocarbon courting methods indicated it was over 35,000 years previous. Within the Nineteen Eighties, one of many current paper’s co-authors advised the landslide concept—minus the meteorite affect—when he shared proof of an historic rockslide 22 river miles (35 km) downstream of the cave.

In 2019, Jonathan Palmer, one other co-author of the examine and a tree-ring specialist from the College of New South Wales, dated the driftwood to round 55,000 years previous. When Palmer later visited Meteor Crater, he realized that the age of the formation—round 50,000 years—was oddly much like that of the wooden.

“Now there was this query, utterly out of the blue, that no person had requested earlier than,” Chris Baisan, co-lead writer of the examine and senior analysis specialist on the College of Arizona’s Tree-Ring Lab, mentioned within the college statement.

The researchers then recovered and dated further sediment and wooden samples from a web site downstream from Stanton’s Cave, positioned at an analogous top above the river, each of which turned out to be 55,600 years previous.

“The imply of radiocarbon dates from driftwood, IRSL dates from cave sediment, and dates on the Meteor Crater affect converge right into a slender window of time at 55.60 ± 1.30 ka [55,600 years ago, +/- 1,300 years], which supplies credence to the speculation that they have been causally associated,” the researchers defined within the examine. What’s extra, the group additionally discovered two locations the place river cobbles cowl dam materials, possible deposited when the river overflowed the dam and commenced to erode it.

As for the meteor affect, David Kring, co-author and Meteor Crater science coordinator, estimated that it will have prompted an earthquake 100 miles (160.9 kilometers) away on the Grand Canyon with a magnitude of between 3.5 and 4.1. The occasion’s shock wave, blast wave, and affect might have triggered the landslide, Baisan defined within the assertion.

“We put collectively these arguments with out claiming we now have closing proof,” Karlstrom admitted. “There are different prospects, corresponding to a random rockfall or native earthquake inside a thousand years of the Meteor Crater affect that would have occurred independently. However, the meteorite affect, the large landslide, the lake deposits and the driftwood excessive above river stage are all uncommon and strange occurrences.”

As if meteorites weren’t scary sufficient, it looks as if we’d have yet one more factor to fret about if scientists’ projections for asteroid 2024 YR4 turn out to be unsuitable—big landslides.