Seismograph installed at Lake County preserve

In a field near the old visitors center at Ryerson Woods in southeast Lake County, equipment is being installed as part of a nationwide project that has piqued the interest of those who study the earth.

A seismic station that measures how the ground moves, will be set seven feet below the surface as the next wave in the USArray, a 10-year continental-scale seismic observatory.

As one of 400 portable seismic stations, the equipment will be able to continuously sense, record and transmit ground motions, including local and distant earthquakes, according to EarthScope, a program that deploys thousands of instruments to study the structure and evolution of North America.

“It's fundamental research funded by the National Science Foundation. Every seismologist or every geophysicist in the U.S. is part of this or is interested in this,” explained Suzan van der Lee, a seismologist and associate professor of earth and planetary sciences at Northwestern University.

“It's been rolling along slowly toward the East Coast and is coming to Illinois.”

The stations are set up in a grid pattern about 45 miles apart. The closest installments to Ryerson are in the Joliet and Sycamore areas, said van der Lee, who supervised the students who found and secured about two dozen locations.

Locations are to fall within broad circles in a given area. Nearly all the locations in the circle for this area were excluded because of the dense population, according to van der Lee.

“They selected Ryerson because of its relative remoteness to heavy traffic — they wanted to have some place that was fairly tranquil so they could read the vibrations of the earth's movement instead of what's happening on the surface,” said Nan Buckardt, director of environmental education and public affairs for the Lake County Forest Preserve District, which includes Ryerson among its holdings.

The housing for the equipment has been installed, with the actual instruments expected soon. Van der Lee said the equipment will remain there for about two years before being moved to another site.

Earthquakes are rare in Illinois but not impossible, van der Lee said, with a 3.8 magnitude earthquake near Virgil in Kane County recorded in February 2010, for example.

Residents here can feel the effects of distant events, like those in Virginia this year and Ontario last year. How much one feels the effects depends on the structure of the crust of Illinois and between Illinois and the earthquake, she added.

At Ryerson, measurements will help scientists determine this structure and how it varies from county to county and state to state. It can also be used to predict ground shaking for hypothetical future earthquakes in or near Illinois, according to van der Lee.

But the main goals of EarthScope are to explore the structure and evolution of the North American continent, as well as the processes that cause earthquakes and volcanic eruptions, she said.

“This is a research effort to study the deep structure of the continent,” she said.

Data will be transferred live and available online. An interactive kiosk eventually will be set up at Ryerson with connections to the seismometer and general information.

“It's interesting on a very local level but it's significant nationally,” Buckardt said. “It's just kind of cool. People don't think of how an earthquake on the West Coast, where they're more prevalent, can be recorded in the Midwest.”