Featured Map for 22 February 2011:
Earthquake Escape Foiled

Living in California, near the San Andreas Fault, one expects the occasional earthquake. Leaving California for a vacation in Costa Rica we expected to escape earthquakes, but at dinner on our first full day in Costa Rica we were treated to a magnitude 4.6 earthquake.

After the shaking stopped, the first question was whether it was in fact an earthquake (maybe it was just a strong wind), next was to wonder how far it was to the epicenter. Sitting in the shadow of a volcano another thought was whether it was a precursor to a major eruption. Answering those questions took three easy steps:

1. Our location was quickly identified using the GPS capability of an iPhone
2. The location of the epicenter and other details were easily found from the U.S. Geologicl Survey Earthquake Hazards Program
3. Entering the two coordinates in the Great Circle Mapper gave a distance and heading

Today's featured map shows that the earthquake had an epicenter south-southwest of our hotel; click on the map where you'll find that it was about 30 km away.

P.S.: If you ever feel an earthquake, make sure you are safe, then once the festivities are over please go to the USGS site for your earthquake and fill out the "Did you feel it?" form.

References and additional information:

• Magnitude 4.6 – Costa Rica
• Costa Rica Volcanoes and Volcanics – USGS Cascades Volcano Observatory
• Arenal Volcano – Wikipedia
• Arenal Kioro Hotel
• Arenal Kioro Hotel – Heliport