A meteorite impression hundreds of years in the past could have triggered a landslide within the Grand Canyon and reshaped the Colorado River that runs by means of the nationwide park.
Geologists finding out driftwood and lake sediments present in Stanton’s Cave — in Marble Canyon, which lies within the jap a part of the Grand Canyon — revealed a potential connection between the realm and the well-known impression web site often known as Meteor Crater (additionally referred to as Barringer Crater) in northern Arizona.
Via excavation and a number of rounds of radiocarbon relationship, researchers decided the driftwood is about 56,000 years outdated. But at this time, the mouth of Stanton’s Cave sits 150 toes (46 meters) above the Colorado River. A brand new examine suggests the wooden was carried there by an historical paleolake, fashioned when a large landslide dammed the river.
“It might have required a 10-times-bigger flood stage than any flood that has occurred up to now a number of thousand years,” Karl Karlstrom, co-lead creator of the examine and an Earth and planetary science professor on the College of New Mexico, stated in a press release from the college.
The examine claims that the strike that created Meteor Crater may very well be linked to a paleolake — an historical lake that existed up to now however has since dried up — within the Grand Canyon that fashioned on the identical time. The impression would have generated an earthquake round magnitude 5.4 to six, which might have despatched a shock wave highly effective sufficient to shake unfastened unstable cliffs within the Grand Canyon 100 miles (161 kilometers) away and set off a large landslide. That occasion, in flip, might have deposited sufficient particles to dam the river and kind a lake.
Different caves excessive above the river have additionally been explored for clues in regards to the canyon’s geological previous. Along with the driftwood, historical beaver tracks have been present in areas that might be inaccessible to the water-dwelling animals at this time, additional supporting the concept a paleolake as soon as existed within the space.
With driftwood and sediment samples discovered in lots of caves as excessive up as 3,084 toes (940 m), the researchers estimate the paleolake would have been about 50 miles (80 km) lengthy and practically 300 toes (91 m) deep. Over time, the dam that blocked the Colorado River might have been overtopped and deeply eroded, finally filling up with sediment.
Whereas there may be proof linking the paleolake, the meteorite impression and ensuing landslide, the researchers famous that additional examine is required to remove another potential explanations for the river damming, comparable to random rockfall or a extra native earthquake across the identical time.
Their findings have been printed July 15 within the journal Geology.
