University of Pittsburgh
October 27, 2009

Pitt's New Seismic Station Connects Region With Global Network of Scientists Unraveling Earth's Structure Through Quake Data

New facility at the Allegheny Observatory revives Pitt's long-lost seismographic capabilities, detects earthquakes around the world, feeding readings into public real-time Web site
Contact:  412-624-4147

PITTSBURGH-A seismic station newly installed at the University of Pittsburgh's Allegheny Observatory revives Pitt's long-dormant work in seismology and-as the region's only seismic station-unites Western Pennsylvania with a global network of scientists aiming to better understand the Earth's structure.

Maintained by the Department of Geology and Planetary Science in Pitt's School of Arts and Sciences, Pitt's installation boasts a highly sensitive seismograph-a heavy steel canister that must be perfectly level-that can detect as little as a half-nanometer-per-second displacement of the Earth's crust caused by earthquakes anywhere in the world. (The seismograph also senses tremors generated by large waves, storms, explosions, and mine collapses.) Pitt feeds its earthquake readings into the public database of the Incorporated Research Institutions for Seismology (IRIS), a consortium of universities sponsored by the National Science Foundation that pools and analyzes seismic data.

Pitt professor of geophysics William Harbert, who oversees the seismic station, said that the Pitt station's record of ground-trembling events elsewhere reveals details about the Earth's internal structure and how landmasses are linked. Shortly after Pitt's station came online, Harbert said, it detected a rumbling 18 kilometers (11 miles) beneath Pittsburgh that radiated from a 6.2-magnitude earthquake that shook Alaska's Aleutian Islands-nearly 4,000 miles away-on Oct. 12.

"When combined with information about the same earthquake from around the world, our record would help capture the complexities of the Earth's composition," Harbert said. "The goal of IRIS is to establish as dense a concentration of data stations as possible. Pitt's station fills in a data gap and places us in a group of universities and institutions responsible for providing the accounts seismologists need to know how seismic activity in one area of the world resonates everywhere."

The Allegheny Observatory station restores a 70-year-old legacy of seismic research at Pitt. At the behest of the late Pitt Chancellor John Bowman, the Cathedral of Learning originally housed an earth-floor "seismic vault" equipped with a state-of-the-art seismograph constructed at the California Institute of Technology. The antiquated apparatus was dismantled several decades ago, and the site currently stores artifacts for Pitt's Nationality Rooms.

The new station-identified on IRIS as "UPAO"-hooks into two IRIS networks: The "REALTIME" network of nearly 1,900 stations around the world that instantly displays earthquake data, and the "US-REGIONAL" network based at Pennsylvania State University that includes approximately 2,000 stations in the United States and Puerto Rico. Pitt belongs to a five-station sub-network that also includes seismic stations at the Pennsylvania Geological Survey near Harrisburg, on Penn State campus and at a Penn State substation outside of Philadelphia, and at North Carolina Agricultural and Technical State University.

Relevant to Pittsburgh, the Pitt station can indicate how events several thousand miles away manifest locally and what that signifies about Pittsburgh's geology, Harbert said. In addition, he will focus the station's capabilities on more local activity such as storms on the Great Lakes and the East Coast, as well as such new research areas as determining the possible consequences of underground carbon sequestration.

"There are questions we can answer, from 'How many small earthquakes have occurred in this area that the national network didn't pick up' to whether we'll create small earthquakes by pumping carbon into the ground and displacing the soil," he said. "There is so much we can learn about our region because of this."

Pitt's seismograph also will be used in education. An ongoing project between Pitt and the Carnegie Museum of Natural History seeks to eventually have information from Pitt's seismograph displayed in the museum. Harbert also will use the station's readings in his geophysics classes to demonstrate how scientists determine the location and magnitude of earthquakes.

More information on and data from Pitt's seismic station is available on the IRIS Web site at www.iris.edu/mda/PE/UPAO

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10/28/09/tmw