In a surprising twist, two of Arizona’s most iconic landmarks—Meteor Crater and the Grand Canyon—may be linked by a cosmic event that occurred around 56,000 years ago. According to a new study, the asteroid responsible for forming Meteor Crater might also have played a key role in creating a temporary lake within the Grand Canyon.
Cosmic Impact and Geological Shake-Up
The asteroid responsible for creating Meteor Crater—also known as Barringer Meteor Crater—was a massive nickel-iron asteroid weighing 300,000 tons. When it collided with the Colorado Plateau, it released an enormous amount of energy, equivalent to more than 150 atomic bombs. This event, occurring around 56,000 years ago, resulted in the creation of the largest meteor crater in the United States. However, its impact didn’t end there.
The shockwaves from the asteroid’s collision were felt far beyond the immediate area. These seismic waves traveled over 100 miles, reaching the Grand Canyon in a matter of seconds. The force of the shockwave was so powerful that it is believed to have caused a rockslide in the Grand Canyon, damming the Colorado River.
This temporary barrier created an ancient lake in the canyon, stretching for over 80 kilometers (50 miles) and reaching depths of more than 100 meters (370 feet). Today, the site of this once-formed lake is located in what is now Nankoweap Canyon.
A Surprising Source of Evidence
Researchers studying the event found key evidence for this ancient lake in Stanton’s Cave, which lies nearly 45 meters above the Colorado River. Here, the team uncovered driftwood and lake sediments that were critical in linking the ancient lake to the asteroid impact.
According to Karl Karlstrom, a geologist at the University of New Mexico and co-lead author of the study, “Carrying the driftwood up to the cave required a 10 times bigger flood level than any flood that has happened in the past several thousand years.”
The driftwood, which had been collected in 1970 and initially dated in the 1980s, was found to be around 44,000 years old—near the limit of radiocarbon dating at the time. Subsequent testing of additional driftwood samples, found in another alcove above the river, used modern techniques to provide more accurate dates, which all converged on the 55,600-year mark.
The Mystery of the Nankoweap Paleolake
The Nankoweap Paleolake‘s formation was a critical part of this discovery. Researchers identified evidence of a natural dam about 35 kilometers downstream of Stanton’s Cave. Interestingly, this ancient dam material was found to be covered with river cobbles, indicating that the Colorado River had once overtopped the dam over a span of approximately 1,000 years.
The flood caused by the impact-generated earthquake was so significant that it could only have been the result of a seismic shockwave capable of generating a magnitude 3.5 earthquake. This event created the Nankoweap Paleolake, providing an extraordinary insight into the power of cosmic events.
The study highlights that while it’s possible the paleolake was caused by a natural landslide or an unrelated earthquake, the combination of the impact, seismic activity, and the timing of the driftwood and sediment layers creates an undeniable link.
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