August 27, 2009

Listening to the belly of the earth

Listening to the belly of the earth
EarthScope project in northern Sheridan County
By ALLAN TINKER
With the same ability to hear bowel sounds of the earth as a physician might hear human function, the EarthScope “stethoscopes” of listening devices, data recorders, and digital transmission of data are tracking the earth’s movements far below the surface.
Buried 65 inches deep, a 42-inch ADS plastic sewer pipe holds the data recording and computer equipment necessary to sense what is, or is not, going on underground. The project, one that is moving across the US in small increments, pulling up old sites and plopping down new ones a few miles further, is nearly halfway across the US.
According to EarthScope website information, a transportable array of 400 portable, unmanned three-component broadband seismometers deployed on a uniform grid that is systematically covering the US. Each US array station includes the instrumentation necessary to continuously sense, record, and transmit ground motions from a wide range of seismic sources, including local and distant earthquakes, volcanic eruptions, and other natural and human-induced activities.
To meet EarthScope’s scientific goals, hundreds of stations have been installed across the country, including a 3.2km borehole into the San Andreas Fault.
 


The Weather Network