ISGS - July 2004 Activity Highlights

ISGS Investigates Causes, Effects of Northern Illinois Temblor

The magnitude 4.2 earthquake that rattled Midwestern residents on the early morning of June 28 caused minimal damage, but its aftereffects could help seismologists better understand the causes of puzzling mid-continental earthquakes. The earthquake's focus was 3 miles underground on the side of a structure called the Peru Monocline that was also the site of a September 1999 earthquake near Amboy. The day after the June earthquake, seismologists from the Center for Earthquake Research and Information in Memphis, TN, worked with ISGS geophysicists and geologists from the local area to install sensitive portable seismographs to detect any small aftershocks that occur in the area. Three aftershocks have been detected through July 15 and they may provide more information about the bedrock structure that is producing the quakes. (Contact: T. Larson)

Pilot-Scale Test for Concrete Blocks Successful

Screening tests on Illinois coal fly ash have indicated that the majority of them are suitable for autoclaved aerated concrete (AAC) production. A pilot-scale commercial-size test of blocks made from a mixture of fly ash from two Illinois sources collected from the Marion power plant in southern Illinois, was successfully conducted. The results demonstrated that the AAC blocks showed excellent chemical, physical, and engineering properties. Since many utility plants are converting their old coal-burning units to adopt fluidized bed combustion (FBC) fly ash systems to lower emission levels, this process might prove useful in solving the problems associated with the disposal of FBC ash. (Contact: J. Chou)

Mapping of Fireclays and Shales Near Illinois Power Plants

In order to determine the nature and extent of clay/shale resources that could be mixed with locally produced fly ash waste to manufacture bricks, data collected by ISGS geologists within the Danville and Marion study areas of the project were extensively checked for errors. The corrected data for the Danville area were entered into a GIS database and used to produce two sets of maps, one of the surface elevations, overburden thickness, and shale thickness, and another, showing cultural and environmental features. Once these two sets are merged, the resulting maps will show the subsurface data overlay of surface features necessary to define the viable areas for shale production. (Contacts: K. Keith, C. Majerczyk, H. Leetaru)

IBHE-Funded Research Projects Train ISU Geology Students

Until the available funds from the IBHE grant lapsed on June 30, ISGS geophysicists had been working with nine students to collect seismic profiling data needed to continue mapping the shape and location of the Ticona Bedrock Valley in La Salle County. The valley is regarded as a potential important source of groundwater for the region.

With support from NICOR Gas company, several ISU students received training in the use of ISGS's seismic profiling equipment and collected several miles of high resolution shear-wave profiles across the Troy Grove gas storage field. Later in the summer, P-wave seismic data will be collected. The surveys are being used to investigate the relationships between reports of gas leaking from the storage field and shallow geologic structures. (Contacts: A. Pugin, T. Larson)

New ISGS County Map Provides Peace of Mind and Saves Money for Insurance Fund

In response to a recent request from the Illinois Mine Subsidence Insurance Fund, an ISGS scientist provided information available on a mine in Christian County. Homeowners in its vicinity were experiencing problems with ground settling and movement, and the area designated as undermined on an existing map was found to have an unreliable source for the outline of the mine in question. The newly updated ISGS county map for Christian County was used to check out the area and likely saved the company involved and IMSIF from investing further in costly additional geotechnical investigations, as well as a potential lawsuit. (Contact: C. Chenoweth)

Resource Investigations for Kane County

An ISGS scientist investigating the feasibility of Kane County obtaining groundwater from Quaternary sand and gravel deposits, delivered his interim report entitled "Kane County Resources Investigations: Interim Report on Geologic Investigations" to county officials. He also submitted computer-based files of preliminary maps of the bedrock geology, aquifer sensitivity to contamination, Quaternary aquifers, a 3-D geologic model, and a geologic cross section. These were developed using the project database derived from ISWS well records used for synoptic measurements in Kane County. (Contact: W. Dey)

Isotope Geochemistry Report

Using stable isotope and chemical parameters, an ISGS scientist prepared a report for SHN Consultants & Geologists summarizing the isotope results of aqueous samples collected from monitoring wells near a municipal landfill. Whereas the sulfur isotope results indicated that the large sulfate concentrations observed in down gradient wells originated from oxidation of mineralized sulfides in the geological strata, other isotope results indicated that these wells had been impacted by the landfill leachate. These results will be used by the consulting firm and the landfill owners to determine the type of remedial action needed. (Contact: K. Hackley)

New Data for the Carbon Sequestration Project

ISGS geologists are working with colleagues at the Indiana and Kentucky Geological Surveys to complete draft maps of the extent, thickness, and depth for the Survant Coal, a seam which is important in the southeastern portion of the Illinois Basin, as a possible target as a coal sink for the Carbon Sequestration project. Unlike most of the major seams in the area, the Survant has not been previously mapped as part of earlier coal resource assessments. As such, this will be a valuable addition to the knowledge of the Survant Coal's CO₂ sequestration potential. (Contact: C. Korose)

Tests Will Determine Background Levels of Asbestos in Beach Sands

Samples of beach sands collected between June 30 and July 14 at Oak Street Beach in Chicago, Highland Park Beach, Grant Park Beach in South Milwaukee will be tested for their content of asbestos by United Analytic Services. The samples collected downdrift and updrift from Illinois Beach State Park should provide a means of estimating just how much of the asbestos in the sand at Illinois Beach comes from manufactured materials and how much comes from natural sources in the glacial materials in the bluffs that line the Lake Michigan shoreline. (Contact: M. Chrzastowski)

Can Carbon in Fly Ash Help Scrubbers Capture Mercury?

That's the question ISGS researchers are pursuing in cooperation with the Electric Power Research Institute and colleagues at several research companies. The research will examine the fundamental chemistry of interactions between fine particles of partially burned carbon in the exhaust from coal-fired power plants and the various types of mercury present in the gases. The carbon particles may help to convert some of the elemental mercury in the gases into the oxidized form of mercury that is easily captured by the wet scrubbers used to remove sulfur from the exhaust gases. In pilot-scale tests funded by EPRI and USDOE, a carbon-based catalyst developed by the ISGS has successfully converted as much as 95% of the elemental mercury in flue gases to the oxidized form. Additional funding is being sought from USDOE to continue investigations on the use of fly-ash carbon to reduce concentrations of mercury and NOX in flue gas. (Contact: M. Rostam-Abadi)

Updated 08/08/2012 SLD