Geological Clues Connect Arizona Meteor Impact To Massive Landslide In Grand Canyon
A new study highlights the striking coincidence in the geologic ages of the famous Meteor Crater in Arizona and a landslide dam that blocked the Colorado River, forming a paleolake in the Grand Canyon 56,000 years ago.
Driftwood and lake sediments have been long known in a cave called Stanton's cave in Marble Canyon of eastern Grand Canyon. The mouth of the cave is 45 meter above the river, so how did they end up there?
'It would have required a ten-times bigger flood level than any flood that has happened in the past several thousand years. Or maybe they are very old deposits left as the river carved down, or maybe they floated in from a paleolake caused by a downstream lava dam or landslide dam? We needed to know the age of the cave deposits,' explains Karl Karlstrom, emeritus earth science professor at the University of New Mexico and lead author of the study.
In the mid 1960's, Karlstrom's father, Thor, was in the cave as part of a cross-disciplinary geology-archeology research. They found evidence of species that went extinct in Grand Canyon like the California condor and Harrington's Mountain goat; they also found split twig figurines made 3,000 to 4,000 years ago by the ancestors of tribes that live around Grand Canyon. The driftwood was dated to be greater than 35,000 years which was near the limit of the radiocarbon dating method at the time; this age got recalculated in 1984 to 43,500 years. The new study, using new methods and analyses from two labs in New Zealand and Australia reports a date of 56,000 years old.
In the 1980's Richard Hereford of the USGS in Flagstaff had proposed that there was a rockslide near Nankoweap Canyon, about 35 kilometers downstream of Stanton's Cave, that might have formed a dam and a paleolake that backed up water and that allowed driftwood to float into Stanton's cave. If so, driftwood should be found also in other caves, flooded at the same time.
'From numerous research trips, Karl and I knew of other high-accessible caves that had both driftwood and sediment that could be dated,' says coauthor Dr. Laurie J. Crossey. The additional wood samples provided ages around 55,600 years. In one — now almost inaccessible — cave there were even beaver tracks preserved in the sand, suggesting that high water levels persisted for quite some time. Based on sedimentation rates in the canyon, the paleolake likely existed for at least 1,000 years before filling up or breaching the landslide dam.
Conceptualization of Nankoweap landslide that brought down large boulders of Kaibab Limestone from ... More the cliffs at left and created a geologically short-lived paleolake in Grand Canyon. Karl Karlstrom/University of New Mexico
Landslides can be triggered by erosion, earthquakes or volcanic eruptions, but in theory also the shock waves of an asteroid impact could be
Coauthor Dr. David Kring, head of the Center for Lunar Science and Exploration, University of Colorado Boulder, and an expert on the famous Meteor Crater in Arizona, had been working to recalculate the age of the crater, concluding that the impact happened 53,000 to 63,000 years ago.
Was the Meteor Crater impact enough to cause such a landslide? Kring has written about the physics of this and other impacts and has calculated that the impact would have set off a magnitude 5.4 earthquake (or even M6 using different assumptions) and that the shock wave would still have been ~M3.5 after traveling (in seconds) the 160 kilometers north to Grand Canyon. So, the impact could have 'shaken loose' the steep cliffs of Grand Canyon that were 'waiting and ready to go,' as shown by numerous rock falls that happen in Grand Canyon still today.
"The meteorite impact, the massive landslide, the lake deposits, and the driftwood high above river level are all rare and unusual occurrences. The mean of dates from them converge into a narrow window of time at 55,600 ± 1,300 years ago which gives credence to the hypothesis that they were causally related,' concludes Karlstrom.
The full study, "Grand Canyon landslide-dam and paleolake triggered by the Meteor Crater impact at 56 ka," was published in the journal Geology and can be found online here.
Additional material and interviews provided by University of New Mexico.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
5 hours ago
- Yahoo
Why the Pacific tsunami was smaller than expected
The earthquake near the east coast of the Kamchatka peninsula in Russia on July 30 2025 generated tsunami waves that have reached Hawaii and coastal areas of the US mainland. The earthquake's magnitude of 8.8 is significant, potentially making it one of the largest quakes ever recorded. Countries around much of the Pacific, including in east Asia, North and South America, issued alerts and in some cases evacuation orders in anticipation of potentially devastating waves. Waves of up to four metres hit coastal towns in Kamchatka near where the earthquake struck, apparently causing severe damage in some areas. But in other places waves have been smaller than expected, including in Japan, which is much closer to Kamchatka than most of the Pacific rim. Many warnings have now been downgraded or lifted with relatively little damage. It seems that for the size of the earthquake, the tsunami has been rather smaller than might have been the case. To understand why, we can look to geology. The earthquake was associated with the Pacific tectonic plate, one of several major pieces of the Earth's crust. This pushes north-west against the part of the North American plate that extends west into Russia, and is forced downwards beneath the Kamchatka peninsula in a process called subduction. The United States Geological Survey (USGS) says the average rate of convergence – a measure of plate movement – is around 80mm per year. This is one of the highest rates of relative movement at a plate boundary. But this movement tends to take place as an occasional sudden movement of several metres. In any earthquake of this type and size, the displacement may occur over a contact area between the two tectonic plates of slightly less than 400km by 150km, according to the USGS. The Earth's crust is made of rock that is very hard and brittle at the small scale and near the surface. But over very large areas and depths, it can deform with slightly elastic behaviour. As the subducting slab – the Pacific plate – pushes forward and descends, the depth of the ocean floor may suddenly change. Nearer to the coastline, the crust of the overlying plate may be pushed upward as the other pushed underneath, or – as was the case off Sumatra in 2004 – the outer edge of the overlying plate may be dragged down somewhat before springing back a few metres. It is these near-instantaneous movements of the seabed that generate tsunami waves by displacing huge volumes of ocean water. For example, if the seabed rose just one metre across an area of 200 by 100km where the water is 1km deep, then the volume of water displaced would fill Wembley stadium to the roof 17.5 million times. A one-metre rise like this will then propagate away from the area of the uplift in all directions, interacting with normal wind-generated ocean waves, tides and the shape of the sea floor to produce a series of tsunami waves. In the open ocean, the tsunami wave would not be noticed by boats and ships, which is why a cruise ship in Hawaii was quickly moved out to sea. Waves sculpted by the seabed The tsunami waves travel across the deep ocean at up to 440 miles per hour, so they may be expected to reach any Pacific Ocean coastline within 24 hours. However, some of their energy will dissipate as they cross the ocean, so they will usually be less hazardous at the furthest coastlines away from the earthquake. The hazard arises from how the waves are modified as the seabed rises towards a shoreline. They will slow and, as a result, grow in height, creating a surge of water towards and then beyond the normal coastline. The Kamchatka earthquake was slightly deeper in the Earth's crust (20.7km) than the Sumatran earthquake of 2004 and the Japanese earthquake of 2011. This will have resulted in somewhat less vertical displacement of the seabed, with the movement of that seabed being slightly less instantaneous. This is why we've seen tsunami warnings lifted some time before any tsunami waves would have arrived there. Get your news from actual experts, straight to your inbox. Sign up to our daily newsletter to receive all The Conversation UK's latest coverage of news and research, from politics and business to the arts and sciences. This article is republished from The Conversation under a Creative Commons license. Read the original article. Alan Dykes does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
NBC News
5 hours ago
- NBC News
Massive earthquake off Russia's east coast is one of the most powerful ever recorded
The earthquake that struck Russia's eastern Kamchatka region and triggered tsunami warnings across the Pacific is among the most powerful temblors to have been recorded in modern history. The U.S. Geological Survey (USGS) may revise the magnitude of the earthquake, but if it remains at 8.8, this quake would be tied with the sixth strongest ever, which struck central Chile in 2010, killing more than 500 people and destroying over 370,000 homes. Russian authorities have called the latest quake a 'remarkable event.' It struck at a depth of an estimated 13 miles, about 74 miles off the coast of Petropavlovsk-Kamchatsky, the regional capital on the Kamchatka Peninsula, with a population of 180,000. Despite its strength, early reports indicate that there have been no deaths or significant damage from the event and that recorded tsunami waves reached a maximum of 9.8 to 13.1 feet in Russia, 4.9 feet in Japan and 5.7 feet in Hawaii. David Tappin, principal researcher at the British Geological Survey, said he's surprised by this. 'When I first saw it was 8.8, I must admit, I thought, 'Oh, we're going back to maybe Japan,'' he said, referring to the 2011 earthquake that triggered a huge tsunami, killing more than 20,000 people and causing a meltdown at the Fukushima Daiichi nuclear power plant. Now referred to as the 'Great Tohoku Earthquake,' it had a magnitude of 9.1, the fourth most powerful ever recorded. The waves from that tsunami reached as high as 130 feet, according to the National Oceanic and Atmospheric Administration, hitting the coast at a height of about 50 feet. 'At the present time, it seems quite anomalous. 8.8 magnitude generating a 4-meter tsunami seems very unusual but … the information on the tsunami impact is still quite limited,' Tappin said, adding that he would have expected a tsunami of at least 10 meters, or about 33 feet. He said the relatively insignificant damage reported so far could be due to the remoteness of the epicenter and the effectiveness of the warning systems. 'It seems to me that the warning system kicked in, and warnings were given in Japan initially, Hawaii and off the West Coast of the U.S. So it just demonstrates the importance of having these warning systems,' Tappin said. 'In this instance, perhaps the tsunami wasn't large, but it saves people's lives.' The fifth-strongest earthquake ever recorded, a 9.0 tremor, also hit the Kamchatka region in 1952. Its epicenter was less than 19 miles from this one. In that disaster, the waves reached up to 50 feet and killed at least 1,790 people, with some historians putting the death toll as high as 8,000, according to the Russian Military Historical Society. The region has experienced nearly 700 earthquakes with magnitudes over 5.0 since 1990, according to the USGS. The most powerful earthquake ever recorded was the magnitude-9.5 'Valdivia' or 'Great Chilean' earthquake, which hit central Chile in 1960, killing more than 1,600 people and leaving 2 million homeless. One of the world's most deadly earthquakes was the third most powerful ever recorded, which struck off the coast of Sumatra, Indonesia, on Boxing Day in 2004. The 9.1-magnitude quake triggered massive tsunamis reaching up to 100 feet and killed an estimated 280,000 people.
The Hill
10 hours ago
- The Hill
What is the largest earthquake ever recorded?
An 8.8 magnitude earthquake — one of the most powerful in recorded history — struck off the coast of Russia Tuesday, prompting tsunami watches and warnings around the globe. But how does it measure up with the strongest earthquakes in history? The United States Geological Survey's (USGS) seismogram records only go back to about 1900, but since then there have been multiple quakes that registered at 9.0 magnitude and above. 1. Valdivia Earthquake The most powerful earthquake happened in 1960 in Biobio, Chile. The 9.5 magnitude Valdivia earthquake, also referred to as the Great Chilean Earthquake, killed some 1,655 people and left 2 million homeless, according to the USGS. 2. Great Alaska Earthquake Four years later, a 9.2 magnitude earthquake rocked Alaska, generating a tsunami that, combined with the earthquake, killed at least 130 people and caused over $2 billion in damage, according to the USGS. The earthquake was also known as the Prince William Sound earthquake, or the Good Friday earthquake. 3. Sumatra-Andaman Islands Earthquake A magnitude 9.1 earthquake that shook Sumatra, Indonesia and the Andaman Islands in 2004 caused deadly tsunamis that killed over 280,000 people and left more than 1 million displaced, according to the USGS. Prior to Tuesday's earthquake, the 10 largest earthquakes since 1900 were: 4. Magnitude 9.1 (2011). Tohoku, Japan 5. Magnitude 9.0 (1952). Kamchatka Krai, Russia 6. Magnitude 8.8 (2010). Biobo, Chile 7. Magnitude 8.8 (1906). Esmeraldas, Ecuador 8. Magnitude 8.7 (1965). Alaska, U.S. 9. Magnitude 8.6 (1950) Arunachal Pradesh, India 10. Magnitude 8.6 (2012). Sumatra, Indonesia On Tuesday, a tsunami warning was issued for Alaska, Hawaii and other coasts south toward New Zealand after the earthquake struck roughly 74 miles east-southeast of the Russian city of Petropavlovsk-Kamchatsky, which has a population of 180,000, on the Kamchatka Peninsula. Multiple aftershocks as strong as 6.9 magnitude were recorded. Several locations advised evacuations, but no major injuries have been reported. Cars jammed streets and highways in Honolulu as the tsunami alerts coincided with the Tuesday afternoon rush-hour. Warning sirens blared as people moved to higher ground. Hawaii schools canceled after-school and evening activities. A tsunami of 50 centimeters (1.6 feet) was detected at the Ishinomaki port in northern Japan, according to the Japan Meteorological Agency. That was the highest measurement so far among several locations around northern Japan. The Russian areas nearest the quake's epicenter on the Kamchatka Peninsula reported damage and evacuations, but no serious injuries.
