New Seismograph at UT Dallas Registers
Earth’s Shakes, Rattles and Rolls
$10,000 Instrument an Educational Tool for Geosciences Students
RICHARDSON, Texas (Jan. 14, 2004) – The next time you feel the earth move under your feet, geoscientists at The University of Texas at Dallas (UTD) will be able to tell you when and how much – on a newly-installed seismograph in Founders Hall.
The sensitive scientific instrument, one of only a very few of its kind in the Dallas-Fort Worth area, records seismic waves generated by earthquakes – whether it occurs in an adjoining state or as distant as the other side of the globe. But mostly what it displays — on a computer screen in real-time digital readouts that resemble an electrocardiogram printout – is the “ordinary background noise of the planet,” according to one of the instrument’s builders, Dr. John F. Ferguson, associate professor in UTD’s Department of Geosciences.
“The earth’s surface is in constant motion,” Ferguson said. “These shifts of perhaps only a millionth of a meter are imperceptible to you and me, but are detected by the seismograph and displayed as an ongoing series of small blips in the data stream. However, a moderate earthquake of, say, 4 on the Richter scale 1,000 miles away would result in a much larger blip.”
The seismograph’s display screen has been erected in the lobby of Founders, the university’s main science building, so that students, faculty or passersby can gauge the earth’s seismic mood at any given time. It’s part of a new display — a “mini-museum” — that includes historical geoscientific instruments and equipment, some manufactured by Geophysical Services, Inc., the forerunner of today’s Texas Instruments, whose founders created UTD’s predecessor institution, the Graduate Research Center of the Southwest.
But the heart of the instrument — the seismometers — resides one floor below, in the building’s basement. The seismometers are oriented in such a manner to measure movement of the earth in three directions — up and down, north and south and east and west.
The seismometers sit on a concrete pier which is isolated from the surrounding slab of the building to reduce the chance of vibrations from machinery and other equipment producing a false reading. According to Ferguson, while the slab sits on the surface of the ground, the pier is anchored in bedrock — in this case, a portion of the Austin Chalk formation lying just a meter below the building.
Seismic waves from a temblor are conducted through the bedrock and the attached pier and sensed by the seismometers, then the data is transmitted to the computer screen upstairs.
“When Founders — the first building on our campus — was built in 1964, the concrete pier was included for just this purpose,” Ferguson said.
The seismograph was constructed over a period of about six months by Ferguson and several colleagues, Jerry Beavers and Ray Fuller, who are technical staff members in the Geosciences group. They utilized new and existing equipment, as well as some they built themselves. The cost of the project was approximately $10,000.
“We’ve wanted to install a seismograph at UTD for some time,” Ferguson said. “Its primary purpose is to provide another dimension to our educational efforts in the geosciences.”
According to Ferguson, the instrument should be particularly valuable to students enrolled in undergraduate classes on Geophysics and on Volcanoes and Earthquakes.
Because North Texas is relatively stable from a geological standpoint, few earthquakes occur in the immediate area. The nearest quakes likely to be detected by the UTD seismograph might strike areas of West Texas and the Texas Panhandle, Oklahoma or Mexico, Ferguson said.
About UTD
The University of Texas at Dallas, located at the convergence of Richardson, Plano and Dallas in the heart of the complex of major multinational technology corporations known as the Telecom Corridor®, enrolls about 13,700 students. The school’s freshman class traditionally stands at the forefront of Texas state universities in terms of average SAT scores. The university offers a broad assortment of bachelor’s, master’s and doctoral degree programs. For additional information about UTD, please visit the university’s web site at www.utdallas.edu.