Illinois Geological Quadrangle (IGQ) Digital Expanded Data Product Sample

A sample of an Expanded IGQ Digital Data Product is available for download free-of-charge for the Surficial Geology of the Alton Quadrangle in Madison County, Illinois. Other expanded IGQ digital data products are available for purchase. Images offered via the links below are not cartographic products, they merely portray the general nature of the data.

Alton Surficial Geology

(17Mb)

Surficial geological units of the 7.5-minute Alton Quadrangle in Madison County, Illinois. Vector spatial data layers for surficial geologic units and contacts, loess thickness contours, cross-section line locations, and data points for stratigraphic test holes, outcrops, ISGS field notes, water wells, and engineering borings.

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Contents of the Alton Surficial Geology Expanded IGQ Digital Data Product

Vector spatial data layers in ArcInfo and ArcView data formats.

ArcView project file (.apr) and associated legend files for each vector data layer (.avl)

The following JPEG and TIFF images from the final published map:

GeoTIFF raster data layer of published hard-copy map. (map file detail) .

USGS Digital Raster Graphic (DRG) GeoTIFF image. (DRG file detail).

JPEG browse graphics (the reduced resolution graphics offered above):
Entire Map Sheet, Quadrangle Only, Thumbnail, and Quadrangle Map Location.

JPEG files of map text, legend, figures, and photographs:
Quaternary Geology, Material Resources and Environmental Hazards,
Mapping Techniques, References, Acknowledgements.

Geologic Map Legend, Cross-section A-A', Cross-section B-B'

Photographs: Fig. 1 Clay content of Glasford Formation till, and Fig. 2 Illite content of Glasford Formation till.

Loess at Lohr Quarry, Hairpin erosion marks, Flooding in Alton, Illinois

The following metadata files:

Product Contents, Technical Requirements, and Use Constraints: Readme File.

Surficial Geology of the Alton 7.5-minute Quadrangle: FGDC FAQ and FGDC Outline.

Cross-section line locations: FGDC FAQ Metadata and FGDC Outline.

Data point locations: FGDC FAQ and FGDC Outline.

Map author's detailed notes regarding data points: Word processing document

Loess spatial data: FGDC FAQ and FGDC Outline.

Surficial geological units: FGDC FAQ and FGDC Outline.

Surficial geology GeoTIFF image: FGDC FAQ and FGDC Outline.

USGS DRG GeoTIFF image USGS Metadata.

ESRI XML metadata for all vector and raster data layers.