SNS Outfitter & Guides via Facebook
SNS Outfitter & Guides via Facebook

Massive 'Gash' Splits Open Foothills of Bighorn Mountains

SNS Outfitter & Guides via Facebook
SNS Outfitter & Guides via Facebook

A 150-foot-wide chasm has appeared in the foothills of the Bighorn mountain range in Northern Wyoming. Images of the crack were first posted online on October 23 by local hunting outfitters SNS Outfitter & Guides.

This giant crack in the earth appeared in the last two weeks on a ranch we hunt in the Bighorn Mountains. Everyone here is calling it “the gash”. It’s a really incredible sight.Huntwyo.com

Posted by SNS Outfitter & Guides on Friday, October 23, 2015

Located 10 miles outside the town of Ten Sleeps, "the gash" stretches for 2250 feet. Although it looks like something formed by an earthquake, no seismic activity has been reported in the area. The crack is more likely a slow-moving landslide produced by an especially rainy spring and summer. Acidic rain or subsurface water can sometimes cause carbonate rocks to dissolve, and variations in underground water flow can also threaten the integrity of sediments supporting the surface layer. These factors can trigger the collapse of the surface soil in a similar way to how sinkholes are formed

In light of the curiosity surrounding their first post, SNS brought an engineer to investigate the site. On their Facebook page, they posted the follow-up, "Apparently, a wet spring lubricated across a cap rock. Then, a small spring on either side caused the bottom to slide out. He estimated 15 to 20 million yards of movement."

While cap rocks are naturally strong, the rock that lies beneath them can become unstable when infiltrated by high amounts of water. If the cap rock in this case had slipped off, it would have made the weaker rock beneath it vulnerable to rain. 

Based on the images, Seth WittkeWyoming Geological Survey’s manager of groundwater and geologic hazards and mapping, told the Powell Tribune, "A number of things trigger them, moisture in the subsurface which causes weakness in soil or geology, and any process that would weaken the bedrock or unstabilize it somehow.” Unlike more violent landslides, this one likely occurred at a more gradual pace, according to Wittke.

The survey's public information specialist Chamois Andersen also added, "It is not uncommon to have slides like that." So while unsettling, the crack is thankfully not a sign of seismic catastrophe, as some have feared.

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Interactive Map Shows Where Your House Would Have Been 750 Million Years Ago
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iStock

Your neighborhood traveled a long way over several hundred million years to reach the spot it occupies today. To trace that journey over the ages, check out Ancient Earth, an interactive digital map spotted by Co.Design.

Ancient Earth, a collaboration between engineer and Google alum Ian Webster and Paleomap Project creator C.R. Scotese, contains geographical information for the past 750 million years. Start at the beginning and you'll see unrecognizable blobs of land. As you progress through the ages, the land mass Pangaea gradually breaks apart to form the world map we're all familiar with.

To make the transition even more personal, you can enter your street address to see where it would have been located in each period. Five hundred million years ago, for example, New York City was a small island in the southern hemisphere isolated from any major land mass. Around the same time, London was still a part of Pangaea, and it was practically on top of the South Pole. You can use the arrows on your keyboard to flip through the eras or jump from event to event, like the first appearance of multicellular life or the dinosaur extinction.

As you can see from the visualization, Pangaea didn't break into the seven continents seamlessly. Many of the long-gone continents that formed in the process even have names.

[h/t Co.Design]

Yellowstone's Steamboat Geyser Keeps Erupting, and Scientists Aren't Sure Why

An eruption from Steamboat Geyser in Yellowstone National Park is normally a rare sight, but guests were treated to the geothermic show seven times in the past three months, according to the USGS. The last time the geyser spouted at least three times in a year was 2003, and scientists are still struggling to find out the cause behind the sudden spike in activity.

Old Faithful has garnered fame in Yellowstone and beyond for its regular eruptions that blow every one to two hours, but Steamboat is less reliable. Geysers occur when magma heats up the water and gases trapped in pockets under the ground. If enough pressure builds up, the steam and boiling water will escape through cracks in the earth and shoot past the surface. The reservoir beneath Old Faithful is fairly simple, as geological maps have shown us, and that explains the frequent eruptions. But the structure beneath Steamboat is likely more complicated, leading to eruptions that result from a combination of hard-to-predict factors.

Steamboat's last eruption before this recent marathon of spurts was recorded in September 2014. The geyser's water columns have been know to reach up to 300 feet, making it the tallest active geyser in the world.

Geologists have come up with a few explanations for the phenomena, one being that it was caused by thermal activity in the park's Norris Geyser Basin. Another possibility is that the geyser is having these smaller eruptions closer together in place of one large one. While they haven't come to a consensus on the cause, experts do agree that the frequency of the eruptions is unlike anything they've seen at this geyser before.

While the geyser activity remains a mystery, it shouldn't be taken as an indication that a catastrophic volcanic event is coming to Yellowstone anytime soon. The last volcanic eruption on the park's land took place 70,000 years ago.

[h/t NPR]

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