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Hugh Pickens writes "Science Daily Headlines reports on research by Oregon State University marine geologist Chris Goldfinger showing that earthquakes of magnitude 8.2 (or higher) have occurred 41 times during the past 10,000 years in the Pacific Northwest. By extrapolation, there is a 37% chance of another major earthquake in the area in the next 50 years that could exceed the power of recent seismic events in Chile and Haiti. If a magnitude-9 quake does strike the Cascadia Subduction Zone, extending from northern Vancouver Island to northern California, the ground could shake for several minutes, highways could be torn to pieces, bridges might collapse, and buildings would be damaged or even crumble. If the epicenter is just offshore, coastal residents could have as little as 15 minutes of warning before a tsunami could strike. 'It is not a question of if a major earthquake will strike,' says Goldfinger, 'it is a matter of when. And the "when" is looking like it may not be that far in the future.'" Read below for more.
The last major earthquake to hit the Cascadia Subduction Zone was in January 1700. Scientists are aware of the impact because of written records from Japan documenting the damage caused by the ensuing tsunami, which crested across the Pacific at about 5 meters (15 feet). Knowledge about what happened in Oregon and Washington is more speculative, but the consensus — gleaned from studies of coastal estuaries, land formations, and river channels — is that the physical alteration to the coast was stunning. The outer coastal regions subsided and drowned coastal marshlands and forests, which were subsequently covered with younger sediments. "Perhaps more striking than the probability numbers is that we ... have already gone longer without an earthquake than 75% of the known times between earthquakes in the last 10,000 years," says Goldfinger. "And 50 years from now, that number will rise to 85 percent."

Hugh Pickens writes "Scientists say that sedimentary deposits from more than 20 cores in New York and New Jersey indicate a huge wave crashed into the New York City region 2,300 years ago, dumping sediment and shells across Long Island and New Jersey and casting wood debris far up the Hudson River. Steven Goodbred, an Earth scientist at Vanderbilt University, says that size and distribution of material would require a high velocity wave and strong currents to move it, and it is unlikely that short bursts produced in a storm would suffice. 'If we're wrong, it was one heck of a storm,' says Goodbred. An Atlantic tsunami is rare but not inconceivable, says Neal Driscoll, a geologist from Scripps Institution of Oceanography, who is not associated with the research. The 1929 Grand Banks tsunami in Newfoundland killed more than two dozen people and snapped many transatlantic cables, and was set in motion by a submarine landslide set off by an earthquake."

kingofalaska writes "An accelerating Arctic warming trend over the past quarter of a century has dramatically dried up more than a thousand large lakes in Siberia probably because the permafrost beneath them has begun to thaw, according to a paper to be published the journal Science." From the article at the LA Times: "About 125 of the 1,170 shrunken lakes disappeared altogether, and most are now considerably smaller than the study's baseline of 40 hectares, or about 99 acres, the researchers found. If Arctic temperatures continue to rise, the scientists said, many of the lakes in high northern latitudes, where they are ubiquitous, could eventually disappear."

Iphtashu Fitz writes "Think all earthquakes last only seconds or minutes? Think again! Scientists at the University of Washington are measuring a "slow" earthquake some 12 to 25 miles underground that could last as long as a month. Along with the UW scientists, seismologists at the Geological Survey of Canada and Central Washington University have documented at least nine previous so-called slow earthquakes going back to 1992. They seem to occur every 14 months or so, the last one occuring in February and March of last year. These earthquakes, also known as slow-slip earthqakes, can release as much energy as a magnitude 6.8 earthquake but because it's released over such a long period of time nobody on the surface even notices it. One key question the scientists are trying to answer is whether these slow earthquakes add to or relieve stress in the tectonic plates, which could ultimately help to predict major earthqakes."

rvr writes "Thanks to compression technology that has reduced the file to 3.3 gigabytes and a collaboration between the Canadian Forest Service and the Canadian Space Agency called the 'Earth Observation for Sustainable Development of Forests', this gigantic image -- the highest-resolution image of Canada freely available -- can now be downloaded to your computer."