Saturday, November 3, 2012

NetQuakes...

Something like two years ago, I first read about the U.S. Geological Survey (USGS) “NetQuakes” program.  Basically the USGS wants to get a denser network of seismographs in certain earthquake-prone area, such as southern California.  To reduce the cost of such a network, they came up with a capital idea: enlist a network of volunteer “seismograph hosts”.  Each of these hosts had to have a home with a concrete slab, power, and Internet access.  That describes just about every house around here, including ours.  So I signed up to be a volunteer.

Nothing whatsoever happened after that, until last week – when completely out of the blue, a nice young fellow from USGS called me and asked if I was still interested.  Of course I said yes, and last Thursday he showed up with a GeoSIG IA-2 “Internet Accelerograph” (PDF datasheet) just like the one at right, and a few tools.  I had picked out a spot underneath my IT gear that he thought was just dandy, and in just a few minutes he had the thing installed, powered up, checked out, and connected to the Internet (via WiFi!).  The bracket that holds the instrument (seen in the photo as the metallic plate on the bottom) is bolted to my slab and leveled.  The instrument itself snicks right into that bracket – so as my slab moves, the instrument itself moves.

And exactly what is the instrument?  The summary: a three-axis accelerometer with some smarts around it to pick the “strong motion” events to bother reporting, and to record not only the event itself but some time both before and after it.  The whole thing is running on an ARM processor; the OS is Linux.  Quite the modern piece of gear!

The data it collects is published up to the Internet and is publicly accessible.  The page for my particular instrument is here; a map of all the instruments is here (from here you can get to the data for any instrument).  The image below shows what the seismograph (all three axes) produces for an event it records:

If you'd like to volunteer for NetQuakes, here's the signup page.

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