DEVELOPING A GEODATABASE OF MAQUOKETA’S (IOWA) QUATERNARY GEOLOGY

The Quaternary geology of the 7.5’ Maquoketa Quadrangle was mapped by undergraduate scientists from the University of Northern Iowa (EDMAP - G15AC00209). The study area lies in a terrain of dissected Pre-Illinoian glacial deposits that blanket a Silurian bedrock surface with significant relief. The study area is characterized by two primary landform region types the Iowan Erosion Surface and East Central Iowa Drift Plain. The focus of this secondary deliverable is to characterize the geochemistry of the quadrangle’s sediments and pedogenic developments. Primary sediment assemblages sampled include: Loess uplands, till plains, alluvial valleys and eolian sand ramps. A PANalytical MiniPal4 XRF was used to obtain chemical signatures (weight% & ppm). Preliminary results of the loess upland sediments indicate ranges of: Pb (13.4 to 26.3 ppm), Ni (20.7 to 36.8 ppm), Sr (136.2 to 183.8 ppm), and FeO (3.1 to 5.07%). These data are being used to delineate the complex interrelationships between natural and anthropogenic variables that may influence soil development, surficial to groundwater flow, and contaminate transport through Iowa’s East Central and Southern Drift Plain regions. ArcMap’s uses extend beyond mapping capabilities. Creating a Geodatabase for this project allows the data, site-specific Quaternary information and the chemical results to be included in one specific location. Using ArcMap’s spatial analysis tools will allow analysis of these chemical signatures to be tied to specific locations that can then be employed regionally to interpret where specific elemental concentration and/or contaminations may occur or where specific soil development issues may be occurring.