• What is Colluvium? An Interactive Poster Seeking a Common Definition to Improve International Communication

    This poster first attempts to summarize the variety of definitions for colluvium. Then it begins an experiment of asking viewers to identify the terminology they would use to define colluvium and alluvium as well as distinguish between the two.

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  • Surficial Geology of Iowa

    Raster of the surficial geology of Iowa based on the parent material interpretations of the US Soil Survey. The map is built from delineations made at a 1:15,840 scale, then converted to a 10 m resolution grid. This data set is based on the spatial information in the USDA-NRCS gSSURGO database and soil series characteristics described in the official soil series descriptions (OSD).

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  • The use of soil surveys to aid in geologic mapping with an emphasis on the Eastern and Midwestern United States

    After soil science became established as a scientific discipline, there has been a continued interplay between geologists and soil scientists, both fields benefiting from advancements made by the other. There is strong agreement between preliminary geology maps created from soil maps and traditional geology maps. Despite the results obtained when using soil maps to create surficial geology maps, there is a need for more quantitative studies to assess the degree of compliment between soil-based maps and traditional geology maps, expansion of the technique into a wider range of geologic and climatic environments, and more research in locations that use classification systems other than Soil Taxonomy.

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  • Colluvium vs Alluvium

    Among various Earth scientists, I’ve encountered slightly different definitions for colluvium and, by association, alluvium. The definitions for colluvium and alluvium are interdependent because their respective definitions are partially based on distinguishing one from the other. In other words, a set of characteristics is being used to split into two classes something that could be defined as one thing. Nonetheless, their distinction is important for communicating key characteristics, geomorphic setting, and inferred processes.

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  • Comparison of surficial geology maps based on soil survey and in depth geological survey

    Despite the widespread availability of relatively detailed soil maps in the USA, few areas have a surficial geology map published with as much spatial detail. This apparent gap between disciplines calls to question the accuracy of soil maps to represent the spatial distribution of surficial geologic materials. Therefore, the purpose of this research was to test the agreement between maps from these two sources.

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  • Physiography of the Des Moines Lobe

    This GIS package contains a pair of spatial data sets that have been generated for the purpose of studying the physiography of the Des Moines Lobe landform region. Includes a 10 m resolution grid interpreting the surficial geology from gSSURGO. Also includes a polygon shapefile that delineates the Des Moines Lobe into physiographic regions based on that surficial geology map and relief.

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  • Using soil surveys to map Quaternary parent materials and landforms

    The integration of soil survey maps with Geographic Information Systems (GIS) allows for an almost infinite level of collaboration across disciplines that use information related to soil databases. This study created a Quaternary geologic map by categorizing soil descriptions into a geologic context and joining the attributes with the Soil Survey Geographic (SSURGO) database in ArcGIS®. The resulting map communicates many of the spatial intricacies of the Des Moines Lobe landform with 15 map units based on geologic units.

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