Seismic testing underway downtown

TERRE HAUTE, Ind. (WTHI) - Two months after city officials approved Indiana State University’s plans to drill for oil, crews have begun seismic testing to map out rock formations under downtown Terre Haute.

The testing is performed by a specially-equipped truck which lowers a pad onto the pavement and sends vibrations of different frequencies into the ground. Meanwhile, magnetic sensors placed along the ground measure the vibrations that bounce back from different layers of earth.  Information from those sensors is then sent back to computers which process the information to create a map of formations underground.

“We only see the rock formations and different types of materials, whether it’s gravel, clay, or whatever,” said field manager Jim Mattison. “We don’t see gas or oil or whatever.”

University officials say the slow-moving truck could cause brief, minor lane blockage over the next week-and-a-half.

The streets affected include: Wabash Avenue, Poplar Street, Chestnut Street and Tippecanoe Street between 3rd and 19th Streets. It will also affect 5th, 7th, 8th and 9th Streets between Tippecanoe and Oak Streets.

The testing crews say most residents will not hear or feel the vibrations, and they said passing trains cause more vibration and sound than their equipment.

“When the train’s going by, (the monitor) sees the noise on the instruments and recorder and he stops and waits until the train has passed,” Mattison said. “So, the train is making way more noise than we are with the vibrator.”

Mattison also said the crews have one observer who monitors the level of vibration near brick buildings and other structures to make sure the level of vibration does not risk the building’s safety.