Abstract:
During the last two decades, airborne electromagnetic methods (AEM) have become increasingly popular in hydrogeophysical studies for groundwater resources assessment. A key benefit of using AEM methods is the rapid collection of accurate, high-resolution data with high spatial density, which can greatly improve geologic frameworks of groundwater flow models. In the USA, regional AEM studies in California, Mississippi Alluvial Plain and Nebraska have improved the understanding of groundwater aquifer structure in support of state and local goals related to sustainable groundwater management. Here in Illinois, we are using AEM technology to better map our local groundwater resources like the Mahomet Aquifer in east-central Illinois.
The Mahomet aquifer is an US EPA-designated Sole-Source aquifer, and the only source of drinking water in east-central Illinois. It provides water to nearly 500,000 people for residential, industrial, and agricultural uses. We are using AEM to create high-resolution imaging of geophysical properties to a depth of ~300 meters. AEM is helping unravel detailed characteristics of both aquifer and non-aquifer materials, for better understanding of the hydrogeologic framework. This project will provide the necessary, detailed information to map the Mahomet aquifer in the highest detail possible, to greatly improve groundwater flow models, and ultimately help better predict long-term water supplies. So far, AEM data have been collected in portions of the Mahomet aquifer in Champaign, Ford, Vermillion, Livingston and Iroquois counties.
Bio:
Dr. Kisa Mwakanyamale Gilkie is a research geophysicist at the Illinois State Geological Survey (ISGS), and the lead investigator for the Mahomet Aquifer Mapping Program. In this role, Kisa conducts research using airborne and ground-based geophysical methods to characterize the framework of the Mahomet aquifer. Kisa has a diverse background in geophysics applications for understanding subsurface environments with experience in academic, industry, and research settings.
Dr. Jason Thomason is a geologist at the Illinois State Geological Survey, which is part of the Prairie Research Institute at the University of Illinois. With colleagues and students, Dr. Thomason has been studying the Ice Age history of Illinois for over 20 years and has coordinated geologic mapping and research projects across many parts of the state, largely in northeast Illinois. His current work includes the use of airborne technologies to map aquifer systems, 3D mapping of geologic frameworks, and in-situ testing of glacial-sediment engineering properties
