“Mount St. Helens seized the world’s attention in 1980 when the largest historical landslide on Earth and a powerful explosive eruption reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape.” Quoted from the USGS Fact Sheet titled…. Mount St. Helens, 1980 to Now—What’s Going On?
“Seismic activity at Pavlof Volcano increased this morning commensurate with the presence of an intense thermal anomaly at the summit observed in latest satellite imagery. Similar patterns of seismicity and elevated surface temperatures have previously signaled the onset of eruptive activity at Pavlof. Although not yet visually confirmed, a low-level eruption of lava has likely begun from a summit vent.” Quoted from the Alaska Volcano Observatory.
Most homeowners insurance policies have exclusions that make them worthless when the home is damaged by common geologic problems such as floods, earthquakes, landslides, mine subsidence, cavern collapse and expansive soils. When a home is damaged the homeowner often is surprised that his “all perils” policy has these exclusions.
A magnitude 6.6 earthquake in China killed over 150 people and injured more than 5,000 on Saturday morning. USGS reports that the earthquake is likely to have occurred on the Longmenshan Fault or a tectonically related fault.
The Washington Department of Natural Resources is reporting on the Whidbey Island landslide. They have links to photo collections, official report, the best “before/after” image pair we have seen, geologic map and more.
The Illinois Geological Survey has a publication titled: Karst Landscapes of Illinois. From the publication “Two conditions are necessary for karst landscapes (green areas on map): (1) Soluble rocks, generally limestone and dolostone, must lie at or near the surface of the ground. (2) The loose soil covering the soluble bedrock must be thinner than about 50 feet.”
The Florida Geological Survey has an informative poster titled “Florida’s Sinkholes”. It shows their geographic distribution, explains how they form, describes different sinkhole types, explains why they are a hazard and explains what to do if a sinkhole occurs near your home.
Last week a sinkhole opened beneath a home in Florida while the occupants were sleeping. One man’s bed fell into the sink and the efforts of family and rescue workers were not successful in retrieving him. Now he is presumed dead and demolition equipment is there to remove the structure while the sinkhole continues to enlarge. Injuries from sinkholes are rare but this situation shows how suddenly they can occur.
“What if the February 15, 2013 meteor strike hit the United States, and not Russia? What if it were the size of the meteorite that struck off the coast of Virginia during the age when modern mammals began to appear?” Quoted from the USGS press release.