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A magnitude 6.0 earthquake struck Italy on Sunday, killing several and leaving an estimated 3,000 people homeless. A number of renaissance era buildings were damaged or destroyed in a region known for it's production of Parmigiano and Grana cheeses. [Source: The Seattle Times via ASCE SmartBrief. Image: LUCA BRUNO / THE ASSOCIATED PRESS via Seattle Times]
A backyard-sized sinkhole opened up recently behind a Windermere, Florida home, causing the home to be deemed unsafe. The residents said one of their kids was enjoying a hammock in the area just the night before. All of the kids and pets living in the house were safe even though the roughly 100 foot by 100 foot sinkhole came within about 3 feet of the house. The residents were renting the house and the home owner had sinkhole insurance. [Source: MSN. Image: CBC.CA]
Raw Sinkhole Video
Here is some raw video footage of the sinkhole to give you a better perspective from the ground and the air.
The picturesque Sea Cliff Bridge South of Sydney, Australia has been built only 7 years and is already threatened by a landslide. Portions of the site have moved 1.5 m since 2006. The Australian Roads and Maritime Services (RMS) department reportedly has three options to consider for stabilizing the bridge, and all three involve the construction of a seawall. The project, which was completed in 2005, was designed to avoid rockfall but was not meant to deal with landslide issues. [Source: Illawarra Mercury. Image: SMH]
A couple walking on the beach narrowly missed being crushed by tons of sandstone crumbling from the cliff face. The incident took place in Dorset, UK at a beach that has been known for these types of landslides and slope failures. The woman stopped to pick up a sea shell and the debris came down just in front of them. [Source: Mail Online. Image: BNPS.CO.UK via Daily Mail]
The landmark City of Venice, Italy is known for it's world famous canals, architecture and for some...its flooding. Part of the problem has been blamed on ground subsidence from pumping of shallow ground water in the mid 1900's. A massive project dubbed MOSE has been in progress for some time to build inflatable gates to stop high tides from flooding the Venice lagoon.
A recent paper in the Journal Water Resources Research evaluates the possibility of injecting water into the formations to stop and perhaps even reverse the subsidence. The article from Ars Technica (link below) mentions that the technique was used with some success in the Long Beach, California area. The study authors had no boreholes in the area, but were able to rely on a large volume of high-quality seismic data obtained by the Italian Government from oil companies. Their simulations involved 15 boreholes around the City of Venice pumping seawater continuously for 10 years. At that point, they authors concluded there is the potential to lift the city 25-30 cm. [Source: Ars technica via Geoengineer.org. Image: De Saye / Rapho via arlindo-correia.com]
The Christ Church City Council has issued a notice banning entry to over 500 homes because of risks associated with rockfall, landslides, cliff collapse and other geotechnical problems exacerbated by recent earthquakes. [Source: Scoop News]
This article notes that the combination of shallow water table and crummy soils make it difficult to rebuild safely in the Christchurch, New Zealand business district. Another interesting item mentioned in the article is that the report they are citing indicates that the high variability in liquefaction damage throughout the business district appears to correlate with the paleo channels beneath the city, where the loose, silty alluvial deposits near the old channels were the most susceptible to liquefaction, but the gravelly soils farther away were not. [Source: TVNZ. Image: TVNZ]
A professor from the University of Tasmania and as many as 20 of his students are using two 'OctoKopters' UAVs or unmanned aerial vehicles to create a detailed 3D map of a landslide in Ranelagh, Tasmania, Australia. The UAVs are deployed by Dr. Arko Lucieer and the TerraLuma project team as a cheap alternative to high-resolution satellite imagery. Flying at altitudes ranging from just 50 m to 120 m, they can photograph micro-topography in remarkable detail. The OctoKopter UAV platform runs about $3,000AU (about $3,200US) but with the payload of a digital SLR camera, six-band multispectral sensor and thermal sensor, the cost is more like $60,000AU each (about $65,000US). On a previous project in Antarctica, the team was able to produce 3D point clouds with a 1cm point spacing. Dr. Lucieer is also investigating using the two OctoKopters and a larger third on order by the UTAS School of Geography and Environmental Studies as a cheaper alternative platform for aerial LIDAR surveys. [Source: University of Tasmania, Australia. Image: lucieer.net]
Arizona State University’s School of Earth and Space Exploration has teamed up with the Indonesian-based Bakrie Group to develop an international initiative called the Bakrie Initiative in Geological Hazards to support and promote research in Indonesia on the core geologic topics of volcanoes, earthquakes and hydrothermal systems. [Source: ASU News]
This is kind of interesting. The equivalent of the Oregon Geologic Survey, DOGAMI, has a geologic hazard map of the state that the City of Newport has used as the basis for a geologic hazard building code. This article describes some Recent and proposed changes to that code. Mainly the changes deal with the clarifications to the requirement for a geologic report, not requiring them on properties classified as moderate risk. But I found it interesting that the City Council approved a motion to only display the hazard maps in grayscale at City Meetings because the red color used on the DOGAMI map for high risk areas might scare people off from buying a property. [Source: oregoncoastdailynews]
The new route for Washington State Route 410 will go around the toe of the Nile Valley landslide. The 2009 Nile Valley landslide blocked the highway and diverted the Naches River. The DOT selected the route out of 3 possible options. The other two options were to remove the slide and keep the same alignment, or to make permanent the temporary detour that goes through a normally quiet rural neighborhood. [Source: KIMA CBS 29. Image: WSDOT]
