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: HS2 tunneling machine completes first mile under the Chilterns The first 2,000 ton tunneling machine passed the one mile mark this week during the construction of the first tunnels for HS2. Launched in May, the 170m long Tunnel Boring Machine (TBM) covered the first mile cutting through a mix of chalk and flint beneath the Chiltern hills just outside London. The TBM – named Florence – is one of two identical machines excavating the twin ten-mile-long tunnels. A second machine, Cecilia, is a short way behind, with both TBMs expected to break out in around three years’ time. Designed specifically for the geology of the Chilterns, each machine is a self-contained underground factory, digging the tunnel, lining it with concrete wall segments and grouting them into place as it moves forward. Welcoming the progress, HS2 Ltd Project Client Rohan Perin said: “The 10 mile Chiltern tunnel will take HS2 underneath the hills and safeguard the woodlands and wildlife habits above ground as well as significantly reducing disruption to communities during construction and operation of the new railway. “Once complete, HS2 will offer low carbon journey options linking London with the major cities of the north and releasing capacity for more freight and local trains on our existing mainlines. It’s great to see how much progress has been made over the summer and I’d like to thank the crew of Florence and all the tunneling team for their hard work.” The first two TBMs are operated by HS2’s main works contractor, Align – a joint venture formed of Bouygues Travaux Publics, Sir Robert McAlpine, and VolkerFitzpatrick. A crew of 17 people keep the machines running, working in shifts and supported by over 100 people on the surface, managing the logistics and maintaining the smooth progress of the tunnelling operation. Align Project Director [...]
Source: Researchers in Tasmania design special drill for million-year old ice core project to help find answers to climate crisis | The Singleton Argus | Singleton, NSW Answers to the world's climate crisis may be discovered in a 2.8 kilometer pole of million-year-old ice that is set to be extracted from Antarctica and delivered back to research labs in Tasmania for atmospheric testing. Australian Antarctic Division researchers in Tasmania have designed and manufactured a 400-kilogram drill for the million year old ice core project which is capable of operating in minus 55 degree temperatures. It will bore down into 2.8 kilometers of ice, which is believed to be up to 1.5 million years old, to extract three meter sections of ice, or ice core, at any one time. Up to 8 tons of ice will then be brought back to research labs for AAD researchers to extract data and information about past temperatures, sea ice levels and wind patterns in Antarctica. Australian Antarctic Division engineers spent two months preparing blocks of ice that would replicate Antarctic ice, which were then used to test the specially designed drill. Picture: Australian Antarctic Division It will also be used to answer a "long standing mystery" in Antarctic research about the frequency of ice ages. The project is part of this year's Antarctic research season which has been dubbed the most ambitious season that the AAD have ever undertaken, with 500 scientists and up to 800 tons of cargo to be shipped to Antarctica. Australian Antarctic Division chief scientist Nicole Webster said the million year ice core project is an incredible milestone for climate research. She said layers in the ice core are like "pages in a diary", where tiny air bubbles trapped in the ice core contain atmosphere and other [...]
Source: Project removes old, disused dams to make healthier waterways - VTDigger Seen through the window of Patty Smith’s home in East Bethel, James Rogers, left, and Fran Rhynhart, right, watch as Ben Canonica, of Canonica Farm and Forest, makes a buffer to protect the bank of the Second Branch of the White River while preparing to remove the Hyde Dam on Tuesday, Sept. 15. “As kids, this was our playground,” said Rhynhart. “All the East Bethel village kids would swim here.” Photo by James M. Patterson/Valley News EAST BETHEL — A yellow excavator ambled over the uneven bed of the Second Branch of the White River as it rearranged boulders above the Hyde Dam earlier this month. Within weeks, the dam will be gone, opening 60 miles of waterways for fish passage. From the 1700s to the 1950s, hydropower ruled and the Hyde Dam in turn gave life to a sawmill, a gristmill, a creamery and a woolen mill that employed over 30 workers in 1860. The current dam replaced an older dam destroyed in what is known as the Great Vermont Flood of 1927. These days, industry has departed from the Second Branch. A half-acre plot of empty land on the north side of the dam gives no hint of the artifacts of production buried below. The mill that leans on the southern edge of the dam is now a home. Conservation nonprofits and state agencies worked together to remove the dam, part of a statewide effort to remove out-of-use dams to improve rivers for both wildlife and people. Greg Russ, a watershed restoration coordinator at the White River Partnership who is overseeing the project, estimated that it will cost anywhere between $120,000 and $150,000. He listed many reasons to remove the dam, for both the [...]
Source: Earthquake: 6.1 quake registered near Adak, Alaska - Los Angeles Times A magnitude 6.1 earthquake was reported Friday morning at 4:52 a.m. Pacific time 114 miles from Adak, Alaska, according to the National Oceanic and Atmospheric Administration’s Tsunami Warning System. According to the USGS, the epicenter was more than 100 miles from a city. In the past 10 days, there have been two earthquakes of magnitude 3.0 or greater centered nearby. The earthquake occurred at a depth of 31.1 miles.
Source: Horrocks' Informed Streets Pavement Management Solution Road maintenance is an essential component of city infrastructure. However, deciding what needs to be fixed and when is often a subject of debate. That's where Horrocks' new pavement management system comes it. Using data-driven analysis, it takes some of the guesswork out of the entire process making road maintenance more cost-effective. This will be an exceptionally great tool for cities like Anchorage, Atlanta, Boulder, Chicago, Indianapolis, Little Rock, Los Angeles, San Francisco, New York, and Phoenix. Informed Streets for Pavement Management Horrocks’ new pavement management system has been dubbed Informed Streets. This is simply because it helps create road maintenance schedules, allowing our clients to maximize their budgets by applying the right treatment to the right road at the right time. This system assesses existing pavement conditions and uses predictive models to develop unique, data-driven management plans that optimize costs and upkeep. These plans are created through the following four stages: 1. Initial Assessment and Survey Horrocks’ mobile LiDAR unit during initial survey In the initial phase of service, Horrocks’ in-house survey crews complete a thorough survey and pavement assessment of the roadways. This is done using a truck-mounted Light Detection and Ranging (LiDAR) unit to assess the pavement by collecting one million survey-grade points every second. Our experts then use this data to develop a baseline for a pavement management plan by providing one of two pavement ratings, depending on our client’s needs: the Pavement Surface Evaluation and Rating (PASER) or Pavement Condition Index (PCI). 2. Data Analysis and Planning Once the pavement rating is complete, an online platform is set up for our client, which includes the Informed Streets3D Viewer. Horrocks’ Informed Streets 3D Viewer integrates GIS systems, LiDAR point clouds, and photography in one robust platform that allows for [...]
California Issues Maps of Earthquake Faults to Avoid ‘Potentially Devastating’ Damage to New Buildings
Source: State Issues Maps of Earthquake Faults to Avoid 'Potentially Devastating' Damage to New Buildings - Times of San Diego The Rose Canyon Fault system. Courtesy County News Center Maps released Thursday of earthquake-prone areas are intended to ensure new construction in San Diego does not take place atop dangerous quake faults. Developed by the California Geological Survey, the regulatory Alquist-Priolo Earthquake Fault Zone maps detail where local governments must require site-specific geologic and engineering studies for proposed developments to ensure this hazard is identified and avoided. Generally, new construction for human occupancy must be set back 50 feet from the active surface trace to avoid faults that may break the surface. “Surface fault rupture is the easiest earthquake-related hazard to avoid because you can see the evidence of where it has occurred,” said Steve Bohlen, acting state geologist and head of CGS. “Surface fault rupture means that one side of a fault is moving either vertically or horizontally in relation to the other side. The deformation that movement causes is potentially devastating to buildings and infrastructure.” Two maps of revised Earthquake Fault Zones have been prepared for the Rose Canyon Fault where it comes onshore in Coronado, traversing the San Diego area to the northwest and going back offshore near La Jolla. Each of the maps covers a roughly 60-square-mile quadrangle of territory. The Alquist-Priolo Act was passed into law following the 1971 magnitude 6.6 San Fernando earthquake, which caused extensive surface ruptures that damaged buildings. Not every large earthquake, though, causes surface fault rupture. For example: the Loma Prieta Earthquake of 1989 devastated the Bay Area without breaking the surface. However, the 1992 Landers Earthquake in San Bernardino County caused surface ruptures along 50 miles, with displacements ranging from one inch to 20 feet. “Since the [...]
Source: Dynamic behaviors of wind turbines under wind and earthquake excitations: Journal of Renewable and Sustainable Energy: Vol 13, No 4 Source: How Do Wind Turbines Respond to Winds, Ground Motion During Earthquakes? - AIP Publishing LLC A new study investigates the combined effect of wind and earthquake forces to assess the dynamic behavior of wind turbines. The demand for renewable energy is nowadays at its peak. Wind power is a great source of clean energy and is harvested via wind farms placed in numerous regions across the world. This has led to some winds farms being established in earthquake-prone regions making it important to assess the combined excitation under wind and earthquake forces. In the US, these wind farms are most commonly seen in Alaska, Arkansas, California, Idaho, Illinois, Kentucky, Missouri, Montana, Nevada, Oregon, South Carolina, Tennessee, Utah, Washington, and Wyoming. The study, recently published in the Journal of Renewable and Sustainable Energy, aims at establishing a numerical model that will integrates both seismic, wind, and operation forces of wind turbines to evaluate the performance of the wind turbines. This is referred to as the "fully coupled model". Such models have been tested before but the research team emphasizes that a solid interpretation of the results is still missing. The authors studied a 5MW wind turbine subjected to a combination of wind load and input ground motion with the latter being retrieved from a list of earthquake records. The study provides some interesting findings. The results from the sophisticated numerical models suggest that the wind that acts as a dynamic load for the wind turbine also exerts a damping effect on the response of the structure. In particular, when shaking is strong, the energy absorbed due to the aerodynamic damping is higher than the actual wind loading generates hence, the [...]
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 [...]