ISGS - September 2011 Activity Highlights

Mining in a quarry

Mining Benefits Illinois Economy

In response to an outside request, Subhash Bhagwat provided information regarding the beneficial economic impacts to the local economy of a new mining operation. The impact of any primary employer (mining or any other) in the immediate region is quite similar and comparable. The multiplier effect on the economy is influenced by such factors as (1) spending by employees, (2) money spent by the mine for contractual services hired from the region and its further ripple effects, (3) institutions and businesses (schools, hospitals, shops, etc.) in the region generating economic activities that would at least be diminished without the mining activity, (4) taxes paid to local governments, and (5) construction businesses that directly depend on the mined materials. The employment multiplier can be assumed to be 1:3. That is, three additional jobs are created for every job in the new mine. In dollar terms, the multiplier can vary from 2.5 to 3, depending on differences within the mining sector. Coal mines, for example, deliver coal to power plants that can be close or far away. Construction aggregates, however, are sold mostly within 20 to 30 miles of the mine. Wages in coal mines may also be higher than in pits or quarries. It would probably be fair to assume the overall dollar multiplier to be $2.50 to the Illinois economy for each $1.00 spent for mining.

Field Trips Examine Glacial Features and Major Aggregate Sources

Generalized cross section of the Middle Illinois River valley showing principal lithostratigraphic units at the approximate latitude of Henry, in Marshall County, Illinois

Illinois State Geological Survey scientists conducted several field trips for geological professionals in association with the 48^th Annual Meeting of the American Institute of Professional Geologists, which was being held in Bloomingdale, Illinois, September 10-14, 2011.

On Saturday, September 10, Donald McKay and Richard Berg led a field trip attended by 10 participants. They visited three sites along the middle Illinois River valley that best explained the history of the Ancient Mississippi River (which occupied the middle Illinois River valley prior to about 24,000 years ago). Sites included the 105-foot Clear Creek Section, which features a succession of tills and sands and gravels from the last glaciation (24,000 to 12,000 years B.P.); the Sisters Section, which contains perhaps the best preserved Sangamon interglacial soil in the region (130,000 to 75,000 years B.P.); and the Sandy Creek Section, composed of 130 feet of Illinois Episode sands and gravels (180,000 to 130,000 years B.P.).

On Sunday, September 11, Pius Weibel led a field trip on the geology of the St. Peter Sandstone and the Ottawa-LaSalle area. Stops included a large quarry where the sandstone is mined, as well as natural sandstone exposures at Matthiessen and Starved Rock State Parks. Also discussed were the LaSalle Anticline and the origin of the unique landscape in this part of Illinois.

On Wednesday, September 14, Don Mikulic led a field trip on the Silurian geology of the Chicago area and its contribution to the infrastructure of the Chicago region. The trip featured a stop at the Thornton Quarry where participants examined Silurian rocks and collected fossils. Emphasized on the trip was the fact that Silurian dolomites have played a critical role in the region as a major source of aggregate for very large transportation and municipal engineering projects.

Highlights Archive

Updated 08/06/2012 SLD