Source: US: Magnitude-6.5 earthquake occurs east of Chignik, Alaska Oct. 11 A magnitude-6.5 earthquake occurred off the eastern coast of Alaska Peninsula at around 01:10 AKDT Oct. 11. The epicenter was about 114 km (70 miles) east of Chignik. The tremor occurred at a depth of about 46 km (28 miles). Moderate shaking was likely felt across northern parts of the Aleutian Islands and much of Kodiak Island. There have been no initial reports of damage or casualties as a result of the earthquake; however, significant damage is unlikely. It could take several hours until authorities can conduct comprehensive damage assessments, especially in remote areas. Aftershocks are likely over the coming days. Authorities have not issued any tsunami advisories. Officials may temporarily shut down transportation infrastructure in the tremor zone to check for damage. Minor disruptions could occur during shutdowns, but service will likely resume quickly if no damage is found. Utility outages are possible, particularly near the earthquake's epicenter.
Source: Craig officials warn of landslide danger as fall storm heads for Southeast Alaska Officials in the Prince of Wales Island community of Craig are warning of potential landslides, flooding and high winds this weekend as a powerful fall storm bears down on Southeast Alaska. The strongest in a series of three storms is forecast to arrive Friday night, the National Weather Service said in a special weather statement. The storm could bring potentially damaging winds with gusts up to 70 mph to Southeast Alaska, including Juneau. Rainfall totals are forecast at between three and six inches from Thursday night to Sunday afternoon. Similar conditions resulted in at least seven landslides across Prince of Wales Island after one storm last fall. Forecasters say saturated soils and strong winds are “a good recipe for landslides.” Now, officials in Craig say they’re preparing for power and water outages, landslides and road closures. And they’re asking the public to be ready. In Craig, residents are asked to use caution or avoid the landslide-prone Port St. Nicholas Road from Thursday through Sunday. Officials ask residents to be prepared to shelter in place with plenty of food and water in case roads are closed. Residents should also conserve water and be ready for power outages. High wind watches take effect Friday afternoon for nearly all of Southeast Alaska with the exception of Upper Lynn Canal and the Yakutat area. The weather service says the Gulf of Alaska is expecting 30-foot seas and storm-force winds of 60-70 mph. Widespread gales are possible along inside waters. Meanwhile, city officials in Craig say they’re staging equipment for a potential response and stepping up their monitoring. City officials are asking the public to keep an eye out for hazards and report them to police — specifically, flooding, soil movement, damage to culverts or [...]
Source: University of Nevada, Reno scientists and engineers collaborating on seismic survey for earthquakes | University of Nevada, Reno University of Nevada, Reno scientists and engineers install equipment at Reno Fire Department's Station 5 on Mayberry Drive as part of a seismic study using fiber-optic cable that runs six miles from downtown Reno to west of Reno. A team of scientists and engineers from the University of Nevada, Reno are installing earthquake sensors above ground along a six-mile stretch of an existing fiber-optic telecommunication cable buried under Reno to develop a rigorous and efficient system for subsurface imaging at the large scale, and detecting earthquakes using laser and fiber-optic technology. "We'll be recording seismic signals generated by passing planes, trains and automobiles along the six-mile stretch of currently unused, buried optical fiber that runs west from Virginia Street along California Avenue and on to Mayberry Drive," Scott Tyler, professor of geological sciences and a leading expert in fiber-optic/laser sensing systems, said. "As the vibrations from the transportation system pass through the underlying geology, it causes a very small change in the optical fiber’s length, which can be recorded from the start of the fiber on South Virginia Street, using a laser-based system called Distributed Acoustic Sensing or DAS." The team, led by Elnaz Seylabi, an assistant professor in the civil and environmental engineering department, is also installing three-component high-resolution seismometers along the cable in the study area to compare traditional methods with the new DAS technology that sends a pulse of laser light through the cable and measures the perturbations in the backscattered light from every point along the cable. The fiber optic system is sensitive enough to detect footsteps as well as jet airplanes that fly by. "Instead of using thousands of geophones to measure ground vibration [...]
Source: A Climate Change-Induced Disaster in Denali National Park | Time The Times has recently showcased an article on the current rockslide situation in Denali National Park. The effects of climate change have been dramatic with the current melting of the permafrost. The National Parks Service has recently upped through gravel removal of the Pretty Rocks Landslide in an effort to keep up as the rapidly thawing permafrost picks up pace. Alaska is right now recognized as the country’s fastest-warming state. The landslide hit unprecedented speed 4 weeks ago causing the team to close the back half of the park weeks earlier than anticipated. This only signals bad news as reservations are canceled in the short term and the long term implications are yet unknown. “This is the canary in the coal mine for infrastructure disruption in Alaska,” says the Camp Denali lodge owner Simon Hamm. “If things continue on the path they’re on, it’s not going to just be Pretty Rock—it’s going to be half of the Alaskan highway system.” Rapid deterioration Denali National Park is one of the U.S.’s largest national parks at 6 million acres, and sits about four hours north of Anchorage. While the entrance to the park is certainly beautiful, many people prefer to hop on buses to access the park’s marquee attractions deep down its single 92-mile road: views of Mt. Denali (formerly Mt. McKinley), the highest peak in North America at 20,000 feet; the gleaming Wonder Lake; rolling mountainsides that contain an abundance of wildlife, including grizzly bears, moose, caribou and bighorn sheep. About halfway along the road lies the Pretty Rocks Landslide, a slowly sliding section of earth that acts more like a glacier than a rockfall. Since the 1960s, permafrost deep below the earth’s surface has thawed, causing the soil and [...]