Link Established Between Grand Canyon Landslide and Meteor Crater Impact
A groundbreaking study from the University of New Mexico (UNM) has shed light on a significant geological connection between two iconic landmarks of the American Southwest: the Grand Canyon and the Meteor Crater. Published in the journal Geology, the research highlights how a landslide, triggered by a meteor impact, formed a temporary paleolake in the Grand Canyon approximately 56,000 years ago.
Study Insights and Historical Context
The paper, titled “Grand Canyon landslide-dam and paleolake triggered by the Meteor Crater impact at 56 ka,” documents a remarkable coincidence in the geological timelines of the meteor strike and the landslide that obstructed the Colorado River, creating a geologically brief paleolake. This study reveals a rich history involving generations of scientists and advances in analytical techniques.
According to Karl Karlstrom, a lead author and Distinguished Professor Emeritus at UNM, the research began by questioning unusual geological formations in the area: “It would have required a ten-times bigger flood level than any recorded in the past several thousand years,” he stated. “We needed to ascertain the age of the cave deposits to understand their origins.”
A Journey Through Time: From Past to Present
The groundwork for this inquiry was laid back in the mid-1960s, when Karlstrom’s father, Thor, conducted cross-disciplinary research combining geology and archaeology in nearby caves. They uncovered evidence of extinct species and ancient artifacts, creating a rich tapestry of the area’s ecological history.
Initial radiocarbon dating of driftwood found in these caves indicated ages nearing 35,000 years, eventually recalibrated to approximately 43,500 years in 1984. The current study, however, incorporates advanced dating techniques applied in laboratories across New Zealand and Australia, revealing an age of around 56,000 years.
In-Depth Scientific Collaboration
The study featured contributions from various researchers, including Chris Bastien and David Kring, as well as Jonathan Palmer, who noted the remarkable alignment in ages during a visit to both Meteor Crater and the UA lab. This collaborative effort was crucial in establishing the validity of the hypothesis.
Crossey, another co-author and expert in geology, emphasized the significance of the caves, stating, “From numerous research trips, we identified various caves that both contained driftwood and sediments suitable for dating.” Their findings support the overarching hypothesis that the meteor impact catalyzed significant geological alterations within the area.
The Paleolake Hypothesis Gains Traction
Sending additional driftwood and sediment samples to respective laboratories was a pivotal step in confirming their hypotheses. Remarkably, these samples returned results demonstrating an age of approximately 55,600 years, further underlining the geological connection between the two events.
The research revisits earlier theories put forth by Richard Hereford of the U.S. Geological Survey, who proposed a rockslide near Nankoweap Canyon could have created a dam and paleolake. Emerging evidence points to this hypothesis as a plausible explanation, supported by the discovery of distinctive erosional features and sediment patterns.
Geophysical Implications of Meteor Impact
Kring has calculated the seismic effects of the Meteor Crater impact, suggesting it would have triggered a magnitude 5.4 earthquake, potentially even reaching a magnitude of 6. This seismic activity may have unleashed rockfalls and landslides in the Grand Canyon area, creating conditions ripe for change.
While the findings are compelling, Karlstrom cautions, “We do not claim to have definitive proof; alternative explanations, such as random rockfalls or local seismic events, cannot be entirely ruled out.” However, the alignment in timelines supports the idea of a causal relationship.
Rare Geological Events Converging
The convergence of meteorite impacts, landslides, and paleolake formations presents a unique occurrence of geological significance. The coordination of dates and findings raises intriguing questions about the geological history of the region and its ecological implications.
Final results indicate the paleolake extended significantly above current river levels, supporting the assertion that it backed up water far beyond present-day expectations. Moreover, the evidence suggests that alterations in the landscape could have occurred in less than a millennium, akin to how modern dam systems operate.
In essence, this research provides critical insights into the interplay between extraordinary natural phenomena and geological timeframes, contributing to our understanding of earth’s evolutionary history.
Further Reading: For those interested in exploring the extensive findings and methodology, the study “Grand Canyon landslide-dam and paleolake triggered by the Meteor Crater impact at 56 ka” is available in the journal Geology.