A Meteor Influence Could Have Induced a Big 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 may the fabric probably have reached that peak? In response to Karl Karlstrom, a geologist from the College of New Mexico, it could have needed to be carried by flood ranges ten occasions larger than any seen previously a number of thousand years.

A global crew of researchers proposes a shocking chain of occasions because the offender behind this thriller. They recommend that round 56,000 years in the past, the meteorite influence that created Arizona’s Meteor Crater triggered a landslide massive sufficient to dam the Colorado River and create a (now bygone) lake nearly 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) influence 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 stumbled on the mysterious driftwood in Stanton’s Collapse 1970, when but unrefined radiocarbon courting strategies indicated it was over 35,000 years previous. Within the Nineteen Eighties, one of many latest paper’s co-authors advised the landslide concept—minus the meteorite influence—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 one 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 extra sediment and wooden samples from a web site downstream from Stanton’s Cave, situated at an identical peak 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 influence converge right into a slim window of time at 55.60 ± 1.30 ka [55,600 years ago, +/- 1,300 years], which supplies credence to the speculation that they had been causally associated,” the researchers defined within the examine. What’s extra, the crew additionally discovered two locations the place river cobbles cowl dam materials, probably deposited when the river overflowed the dam and started to erode it.

As for the meteor influence, David Kring, co-author and Meteor Crater science coordinator, estimated that it could 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 influence may have triggered the landslide, Baisan defined within the assertion.

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

As if meteorites weren’t scary sufficient, it looks as if we would have another factor to fret about if scientists’ projections for asteroid 2024 YR4 turn out to be incorrect—big landslides.