September 2005

It’s approaching the one-year anniversary of the renewed activity at Mount St. Helens. To celebrate, the USGS is holding a Media Event on Friday, September 23, 2005, at 10:00 a.m. PDT at the Cascades Volcano Observatory. Any bloggers in the neighborhood want to drop by and blog it? Also, keep your eyes open in the coming week or two for additional mainstream media coverage.

It’s been a year since Mount St Helens suddenly showed signs of volcanic unrest. Join CVO scientists for a retrospective and future analysis of the ongoing eruption.

Daily Mount St. Helens advisory updates, earthquake data and other information can be found on the internet at http://vulcan.wr.usgs.gov/Volcanoes/Cascades/CurrentActivity/current updates.html and http://www.pnsn.org/HELENS/welcome.html

The San Francisco Chronicle has an article on a major earthquake striking the Bay Area and asks if those of us who live here are prepared for what may happen. Based on historical data, that 20th century was fairly quiet for the Bay Area, in terms of the number of severe earthquakes. And don’t be misled by “a few decades”: Statistically speaking, the coming quake is literally as likely to strike, say, next month or next Christmas — or in two minutes — as it is in 2031, the final year of the time window analyzed by the probability study. The group’s overall forecast was that there is a 62 percent probability of at least one 6.7-or-stronger quake between 2002 and 2031.

According to a new study to be published in the jounal of Science, the number of powerful hurricanes in the last 35 years has nearly doubled due to increases in ocean water temperatures. However, the jury is still out on whether or not this warming is due to man. “What we found was rather astonishing,” said Georgia Tech’s Webster. “In the 1970s, there was an average of about 10 Category 4 and 5 hurricanes per year globally. Since 1990, the number of Category 4 and 5 hurricanes has almost doubled, averaging 18 per year globally.” [...] “Category 4 and 5 storms are also making up a larger share of the total number of hurricanes,” said Curry. “These hurricanes made up about 20 percent of all hurricanes in the 1970s, but over the past decade they accounted for about 35 percent.”

An event known as an “episodic tremor and slip” began as predicted in the Pacfic Northwest this week. These tremors are so small that they aren’t felt by humans, however they will cause parts of the Pacfic Northwest and Canada to move roughly 3 millimeters west over the next 2 weeks. The movement is slower than a traditional earthquake but more rapid than the normal creep associated with the fault. It runs in the reverse direction of the normal creep. [...] The event does not mean an earthquake is imminent, but geologists are eager to study it and learn more and they say sooner or later an ETS event is likely to trigger a major quake.

Volcanic ash from Hawaii shows similar properties to Martian dust when it is properly filtered. Because of this, a small company is seeking permission from the state to mine this ash from Mauna Kea, for use by NASA in training for missions to Mars. “You can run a Mars Rover over it to see how it behaves and what kind of traction it gets, how the dust collects, how it obscures the optics, and how it interferes with the mechanics,” Terry told the Advertiser. “It provides a pretty good simulation.” The company wants permission to remove up to 3,520 square yards of the surface soil to excavate the underlying ash to a depth of 2 to 3 feet. All the excavation work would be done by hand.