Sunday, July 18, 2010

Location of Maryland earthqauke

Below is a map posted by the U.S. Geological Survey showing the epicenter of Friday's magnitude 3.6 earthquake in the Washington D.C. area.

The red dot marking the epicenter is adjacent to the major highway 270 which runs from upper left to lower right in the map.

For conspiracy enthusiasts among you, note that just a few hundred meters away you will see the U.S. Department of Energy, formerly the Atomic Energy Commission.

I know this because my first real job after college was with Fairchild Space and Electronics Company, an aerospace firm located across the street. I annotated Fairchild on the map below, although  I don't know what is located there now.

Saturday, July 17, 2010

Washington area shaken by earthquake

Below is a copy of the mini-poster I put up on our seismograph, showing the signal observed here at F&M, about 150 km from the epicenter. More to come.

Sunday, July 11, 2010

CBC coverage of the Quebec quake

Canadian Broadcasting Company has some nice coverage of the recent Quebec quake, as well as related material on the earthquake hazard across Canada.

But in typical Canadian fashion, this photo of a toppled woodpile elicited some pondering about how disastrous Canadian quakes might really be. Zut alors!

Wednesday, July 7, 2010

Magnitude 5 Quebec quake

I was out of town when this one hit near the Canada-U.S. border:

From the USGS:
The June 23, 2010 Val-des-Bois, Quebec earthquake occurred at 1:42 pm local (eastern) time 56 km (35 miles) north of Ottawa, Ontario, Canada's capital city. The preliminary estimate of magnitude (M) is 5.0, at a depth of 16 km (10 miles).

This earthquake occurred near the southern edge of the Western Quebec Seismic Zone. Earthquakes within this zone are mostly small. They tend to cluster in a wide area that is slightly elongated northwest-southeast. Historically, earthquakes in the Western Quebec Seismic Zone have caused damage roughly once a decade. Three or four smaller events each year are felt in the region but are generally too small to cause damage. Still smaller earthquakes are much more common. The largest earthquakes known in this part of Canada occurred in 1935 (M6.1), about 250 km (150 miles) to the northwest of the Val-des-Bois event, and in 1732 (M6.2), about 150 km (100 miles) to the east of the earthquake. The 1732 earthquake caused significant damage in Montreal.
I heard of one Toronto resident who literally felt her bed rolling back and forth. A colleague in Syracuse felt the earth shake as well. This intensity map from the event shows that she was not alone:

Sunday, July 4, 2010

Open letter to the President of the Republic of Italy

From the website of the Italian Istituto Nazionale di Geofisica e Volcanologia:

Two weeks ago in Italy, the L’Aquila Prosecutor’s office indicted scientists, some of them members of the “Commissione Grandi Rischi”(Commission for High Risks), and civil protection officials for manslaughter. The basis for the indictment is that these people did not provide a short-term alarm to the population after a meeting of the Commission held in L’Aquila six days before the Mw 6.3 earthquake that struck that city and the surrounding area.

The allegations against the scientists are completely unfounded. Years of research worldwide have shown that there is currently no scientifically accepted method for short-term earthquake prediction that can reliably be used by Civil Protection authorities for rapid and effective emergency actions.

The international seismological community has long recognized that the best approach to defending populations from catastrophic earthquakes is not through earthquake prediction, but through risk mitigation and the application of appropriate safety measures to prevent buildings from collapsing. In this regard, the development of seismic hazard maps, which provide estimates of the probability of occurrence of predefined values of peak ground motion in a given time period, provide the specifications required by building codes to avoid collapse of buildings and the resulting fatalities

Italy is an earthquake-prone country. An improved seismic hazard map that summarizes decades of research on earthquake occurrence and effects was completed in 2004 (see It is the result of the work of many scientists, it is considered to be one of the best seismic hazard maps in Europe, and it has been used as a basis for the Italian building code beginning in 2008 (“Norme Tecniche per le Costruzioni”, GU n.29 del 04/02/2008). It should be viewed as the primary  contribution of the Italian earthquake scientists to their Country.

Seismic hazard maps must also be used for conveying to the population the basic concepts of earthquake hazard, awareness, preparedness, and response. Increased consciousness of the earthquake hazard and associated risk should also foster further prevention actions by national and local authorities. Overall, earthquake preparedness and damage prevention in the form of retrofitting are not only possible but mandatory in a country affected for the most by moderate size earthquakes that often result in catastrophes for the society because of the large percentage of seismically unreinforced buildings.

Education, awareness, preparedness and retrofitting are the best tools for mitigating the impact of the catastrophic earthquakes that will inevitably affect Italy in the future.

The scientific community involved in earthquake science urges the Italian government, local authorities and decision makers in general, to be proactive in establishing and carrying out local and national programs to support earthquake preparedness and risk mitigation rather than prosecuting scientists for failing to do something they cannot do yet - predict earthquakes.

The President of the Italian Republic is the head of state of Italy and represents national unity. The president's term of office lasts for seven years. The current President of the Republic is Giorgio Napolitano, elected in 2006.

Thursday, July 1, 2010

Scientists May Face Manslaughter Charges After Earthquake

American Geophysical Unon Science Policy Alert 10-18:  22 June 2010

Seven Italian scientists and government officials are under investigation on charges of manslaughter for failure to warn the city of L’Aquila, Italy, before an earthquake hit last year, killing hundreds. The scientists and officials under investigation, who are employees of the National Institute for Geophysics and Volcanology (INGV) and the Civil Protection Department, took part in a meeting of the Major Risks Committee on 31 March 2009. At the meeting, the committee told L’Aquila city officials that “just because a small series of quakes has been observed [in L’Aquila] there is no reason to suggest that the sequence of low-magnitude tremors are a precursor to a major event,” which was deemed “improbable, although not impossible.” However, on 6 April 2009, the city was struck by a Mw 6.3 earthquake that killed 308 people.

The criminal charges against these scientists and officials are unfounded.  Despite decades of scientific research in Italy and in the rest of the world, it is not yet possible to accurately and consistently predict the timing, location, and magnitude of earthquakes before they occur. It is thus incorrect to assume that the L’Aquila earthquake should have been predicted. The charges may also harm international efforts to understand natural disasters and mitigate associated risk, because risk of litigation will discourage scientists and officials from advising their government or even working in the field of seismology and seismic risk assessment.

Science is making critical contributions to the understanding and mitigation of earthquake hazards in Italy and the world. Examples include providing tools such as seismic risk maps to determine areas of greatest vulnerability, improving seismic wave analysis so that we can better understand how the Earth moves during an earthquake, and increasing our capabilities for seismic monitoring and for providing rapid information on earthquake location and severity for early warning systems and first responders.

It is in the best interest of all countries to reduce earthquake vulnerability through awareness, preparation, and mitigation. Local government officials should work with scientists and engineers to prepare for seismic hazards in that region. To truly mitigate earthquake risk, governments must utilize the long-term hazard assessment, post-earthquake Shake Maps, and other tools created by seismologists to educate residents and inform sound infrastructure policy. Communities can increase their earthquake preparedness through implementation of building codes based on these long-term hazard assessments, retrofitting older buildings, improving emergency response, and increasing public awareness of the hazard and individual responsibility during and after these tragic events.

In support of the Italian scientists and officials, the INGV has written an open letter to the President of the Republic of Italy. The letter is open for public signatures and, as of 21 June 2010, has 5,028 signatories from around the world, many of whom are geoscientists. Please sign the letter and pass this information on to your colleagues if you support these seven scientists and officials and their right to conduct best scientific practices without risk of persecution.