A seismograph is a device that detects and records elastic waves (seismicwaves) traveling through the Earth from either a natural source--anearthquake--or an artificial one, such as a mining or construction blast.From this page you can access the records of Millersville's broadbanddigital seismograph. The seismograph records three directions of groundmotion: East-West Horizontal, North-South Horizontal, and Vertical. You can choose to view either the current day's record (Real-Time Data) or therecord from any day back to February 7, 2002 (Archive Data). The terms"Global" and "Local" refer to the degree of filtering applied to therecords. "Global" records are unfiltered and are best for viewingearthquakes with epicenters located far from Millersville. Any earthquakewith a magnitude of at least 6.0 should be detectable, no matter how faraway the epicenter. "Local" records have been filtered to remove thelow-frequency component of the signal. These records are best for viewingseismic "events," whether earthquakes or blasting, that occur in southeastPennsylvania or the immediately surrounding region.
Click on one of the links below to select either the current day's record or an archived record. Each record begins at 0 hours Universal CoordinatedTime (UTC), which is five hours ahead of Eastern Standard Time (EST) or four hours ahead of Eastern Daylight Time (EDT). Thus, each record begins theevening prior to the record date, in terms of local time. Time progressesleft to right on each line, and then line by line down the page. On the Global records, the vertical lines are spaced five minutes apart so each line represents 30 minutes of data. On the Local records, the vertical lines are one minute apart, each line representing 15 minutes of data.
You might also wish to check out Millersville's Foucault Pendulum, which demonstrates the rotation of the Earth.