2008 ISGS Annual Report - University of Illinois at Urbana-Champaign

Botanic Garden, Chicago History Museum, The Field Museum,
Illinois State Museum Chicago Gallery, Museum of Science and
Industry, Newberry Library, and University of Chicago.
After the festival, 26 of the ISGS exhibit panels were installed on
the first floor of the Natural Resources Building on the University of
Illinois Urbana-Champaign campus to inform visitors to the ISGS
headquarters of the scope of the ISGS mapping program.
ISGS Public Field Trips
Approximately 100 people attended each of the ISGS Geological
Science Field Trips offered during fall 2007 and spring 2008. The fall
2007 trip, offered in September and again in October, highlighted
Participants on the Pere Marquette field
trip listen to the legend of the Piasa
Bird, as they view its image on the
limestone bluffs at Piasa Park, Alton,
Illinois.
the geology and natural resources
of Pere Marquette State Park and
the surrounding areas in Jersey and
Madison Counties. The participants
on this trip learned much about the
history of the limestone industry and
Horseshoe Lake field trip participants at Orchard Creek, Rock Springs Hollow
its importance to the development of
Section, examining exposures of Upper Ordovician age Girardeau Limestone.
the area at stops visiting active and
abandoned limestone quarries, historic
Grafton, and Piasa Park. Piasa Park also offered the opportunity
for the visitors to learn about the history of the Piasa Bird image.
The group had a chance to view displays about the historical and
cultural significance and the ecological, transportation, and commercial
importance of the Mississippi, Missouri, and Illinois Rivers at the
National Great Rivers Museum and the Melvin Price Locks and Dam
south of Alton. Along the trip route, participants had the opportunity
to collect fossils, including Gravicalymene celebra, one of the most
famous trilobites in the Midwest, and mineral specimens, including
geodes. Evidence of ancient faulting and folding of rocks and the relationship
between geology and biodiversity were seen and discussed
along the Goat Cliff Trail at Pere Marquette State Park.
The spring field trip, held in April and again in May 2008, was to the
Horseshoe Lake State Conservation Area within Alexander County.
The trip stops focused on river processes and the many faults and
fractures in the area. Participants viewed the landscape changes that
followed the Santa Fe Levee breach during the Great Flood of 1993.
At Horseshoe Lake, they learned that this oxbow lake was formed
approximately 6,000 years ago when the Mississippi River changed
course, cutting off a large meander. Participants then stopped to
see an excellent view of the ancient Ohio River valley and had an
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opportunity to discuss the geological history and changing course
of the Ohio River. They also were able to see a number of faults and
fractures and examine a rare exposure of a graben (a downthrown
block of bedrock bounded by two faults) within the quarry highwall.
Quarry stops also provided opportunities to collect agates and loess
kindchen (unusually shaped calcareous concretions that form in
loess deposits) and to learn about the limestone, novaculite, and
tripoli industries. As expected, given the number of faults seen on the
trip route, among the questions answered by the ISGS geologists
were several concerning southern Illinois’ 5.2-magnitude April 2008
earthquake and its relationship to the New Madrid Seismic Zone.
Geologic Mapping Effort Contributes
to Local Community Education
Geologists and hydrogeologists working on the Great Lakes Geologic
Mapping Coalition project are mapping the surficial geology of
Lake County, Illinois. The goal of the project is to map, in three dimensions,
the geology from land surface to top of bedrock. To accomplish
this, an extensive program of drilling is being used to acquire continuous
high-quality core samples of the sediment. At each borehole location
where significant deposits of sand and gravel are encountered,
a groundwater observation well is installed to monitor long-term water
levels in the aquifer. Several
dozen wells are now emplaced
throughout the county. One such
observation well was installed
at the Deer Park village hall site
near a historic barn that has
been restored to serve as a
facility for village hall meetings
and community events and as a
museum and education center.
Following discussions with Mike
Barnhardt, the ISGS project
leader, staff from the education
center invited the ISGS to
provide material for a display
at the site. In response, several
ISGS staff members prepared a
multi-panel poster for permanent
display that illustrates the
glacial history, sediments, and
hydrogeology at county scale
and also of the local Vehe Farm
ISGS exhibit at Vehe Farm, illustrating the glacial history, sediments, and
hydrogeology of the area.