New FSU seismometer detects earthquakes around the world

The newly installed seismometer at Florida State University’s Department of Earth, Ocean and Atmospheric Science is already helping scientists detect and analyze earthquakes around the globe.

On June 23, just before 11:30 a.m. EDT, the seismometer recorded a magnitude 7.4 earthquake in southern Mexico, centered in the state of Oaxaca. The powerful quake left at least seven people dead and damaged hundreds of homes.

Information from the Florida State University Seismic Observatory, FSUO, was instrumental in supplying real-time data to the U.S. Geological Survey’s National Earthquake Information Center, NEIC, in Golden, Colo., as the Oaxaca quake occurred.

The FSUO, which has been up and running at the university’s new EOAS building since March, consists of a Streckeisen STS-5A seismometer and a Quanterra Q330HR data logging system. Data from the seismometer is digitized and time-tagged before being sent to the NEIC, the Albuquerque Seismological Laboratory, and the Data Management Center at the Incorporated Research Institutions for Seismology, in Seattle.

The NEIC uses data from FSUO and several hundred other seismic stations in the U.S. and around the world to rapidly locate and characterize earthquakes. The information is verified by seismologists and published to the NEIC website within minutes, with the goal of mitigating risks to human life.

The seismometer and data logger were a gift to FSU EOAS from Bob Hutt, a former member of the U.S. Geological Survey's Albuquerque Seismological Laboratory. Hutt received the equipment in April 2017 as a retirement gift from the owner of Quanterra, Inc., Joe Steim.

“When I retired, my wife and I moved to Tallahassee to be close to our son and his family. I knew there were no high-quality, deeply buried seismographs in the area, so I approached the Department of Earth, Ocean, and Atmospheric Science with the idea of cooperating with them on the installation. I did not want to let such a valuable seismometer just sit in my garage or try to operate it in a less than useful manner,” Hutt said.

The borehole seismometer is designed to be installed deep underground to avoid seismic noise near the surface, which includes everything from trees blowing in the wind to vehicle traffic. University officials worked with engineers from GFA International, Inc. to drill a deep borehole adjacent to the new building, allowing the seismometer to be installed in the underlying limestone bedrock approximately 140 feet below ground.

Since the installation, the Oaxaca earthquake is just one of several seismic events that FSUO has detected. In late May, the seismometer picked up on a distant magnitude 5.9 earthquake as it hit the island nation of Tonga in the South Pacific.

“These events demonstrate both the excellent sensitivity and the large recording range of this state-of-the-art seismograph system,” Hutt said.

EOAS officials say the FSUO system is so powerful it can pick up ground movement as low as a magnitude 5 from earthquakes on the other side of the planet and much smaller earthquakes at closer ranges.

Vincent Salters, Earth, Ocean and Atmospheric Science department chair, said the seismometer fills a geographical gap in the global seismic network and provides crucial information for generating an accurate image of the Earth’s interior.

“Earthquakes allow us to obtain a picture of the inside of the Earth, much like an ultrasound allows us to see inside the body. It is a vivid reminder the Earth’s interior is dynamic and impacts the surface that we live on,” Salters said.