The deep web can also provide a treasure trove of information for everything from emergency response and cybersecurity to identity resolution on a person of interest. If you’re not monitoring it regularly, your security team could overlook valuable sources of threat intelligence. But thanks to its sheer size and inaccessibility, the deep web provides a perfect hiding spot for bad actors like criminals and extremist groups. What’s the other 99% out there? That’s what is known as the deep web - a vast repository of information hidden from the causal web searcher. In fact, analysts estimate sites like Google and Bing have indexed less than one percent of the total internet. Any reuse without express permission from the copyright owner is prohibited.Want to know a secret? There’s a huge portion of the web that you can’t access through a traditional search engine. CC BY-NC-ND 3.0Įxcept where otherwise noted, images are subject to copyright. (2021), An iceberg may have initiated a submarine landslide, Eos, 102. The gouges left when icebergs collide with the seafloor might be only the tip of the problem.Ĭhapman, A. “It’s important to be aware of the triggering mechanisms when we’re planning seafloor infrastructure,” Normandeau said. But icebergs can also travel thousands of kilometers, potentially causing landslides far from the Arctic. In Canada, there is a push to connect northern communities with subsea Internet cables, which would be especially at risk. He’s hoping to address this hypothesis in future research.Īs climate change causes more icebergs to break off the existing ice sheets, understanding the risks that icebergs pose could mitigate damage to new infrastructure projects. “They’re much bigger than what we see in the fjords.” Normandeau hypothesizes that when there was an ice sheet in the region around 20,000 years ago, big icebergs broke off and impacted the seabed, causing landslides. “The most surprising result was off the continental slope of Nova Scotia,” Normandeau said. They found several other iceberg pits at landslide head scarps. “The study is important because it brings up a new mechanism and because the observation is good as it gets.” Iceberg Impacts Run DeepĪfter discovering the landslide in Southwind Fjord, the researchers explored maps of the seafloor in other locations. “That’s what I found fascinating about this iceberg study. She said that when researching submarine landslides, researchers must be in the right place at the right time. Morelia Urlaub, a marine geoscientist at GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany, who wasn’t involved in the study, is researching ways to monitor the seafloor and identify new landslides. By analyzing the sediment composition and the slope of the seafloor, they found that the sediment in the area was stable under gravitational load, but the estimated load of the iceberg would have been enough to initiate the slide. But to see it happen? It was a lot of luck.”įor further evidence that the iceberg initiated the landslide, the researchers went back to the core samples they collected in 2018 near the landslide but before it occurred. “We interpret that it’s that impact that created the landslide because when you look at where the iceberg regrounded, that’s exactly where the landslide head scarp is,” said Normandeau. NGeo: Iceberg gouging of continental slopes can initiate submarine landslides, potentially far from the iceberg source region /bS9T7DQk6q A few days later, it capsized and slammed into the ocean floor, regrounding several meters away. Using satellite images from Sentinel-2, they realized that the iceberg they saw the year before eventually ran aground. They noticed a characteristic pit left when an iceberg impacts the seafloor-right at the initiation point of the landslide, known as a head scarp. By comparing the bathymetry data from their two visits to the fjord, they found an intriguing piece of evidence. But to see it happen? It was a lot of luck.”īecause no earthquakes had occurred within 300 kilometers of Southwind Fjord, the researchers looked for other mechanisms. When the researchers returned to Southwind Fjord in 2019, they learned a new landslide had occurred since their previous visit, providing a rare opportunity to look within a short time window and determine what might have caused it. But because most of the ocean floor is irregularly mapped, it is difficult to know when landslides occur and link them with a causal event. In some cases, earthquakes are the culprits. Despite these risks, scientists don’t fully understand the causes of submarine landslides.
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