Reporter Volume 25, No.27 May 5, 1994

By ELLEN GOLDBAUM
News Bureau Staff
Two UB geologists have begun a pilot study funded by Akzo Salt Inc.
that will look at fractures in the earth above Akzo's salt mine in
Retsof. The study will hopefully provide clues about what caused the
collapse of a portion of the mine roof and insights into any possible
further subsidence.
On March 12, the mine, located southwest of Rochester, experienced a
collapse of a 360,000-square-foot area in the 6,000-acre mine that
initially was attributed to an earthquake.
Robert Jacobi, associate professor of geology, and John C. Fountain,
professor of geology, will use geological techniques to try to
identify and trace fractures in the earth near where the collapse
occurred.
"We want to differentiate the local fracture network that was induced
by the collapse from the regional network of fractures in the area,"
said Jacobi. "We're looking for clues, trying to see whether or not
there are some anomalous structures above the roof of the mine that
made those rocks more susceptible to collapse."
Jacobi said they will try to determine whether the regional network
was in some way part of the cause for the roof collapse. "If there
were a sufficient number of intersecting fractures, it could have made
the roof very weak, compared to elsewhere in the mine," he explained.
Hamish Miller, a consultant for Akzo Salt, Inc. and research director
at the University of Missouri at Rolla, said that "in order to
understand the mine collapse, we need all the information that can
possibly be gathered."
Jacobi and Fountain also hope to determine whether the fractures
observed at the surface are pathways for the natural gas that was
seeping into the mine after the collapse from the rocks just below the
earth's surface.
They will also fly a small plane over the area to take infrared
photographs that they will analyze for surface features that may
indicate fractures.