Engineering Geology of Selected Areas, US Army Engineer Division, Lower Mississippi Valley. Report 1. The American Bottom Area, MO-IL. Volume 1

摘要

The purpose of the report is to characterize the geotechnical parameters of the American Bottom area in the vicinity of East St. Louis, Illinois, and Missouri. The area encompassed is equivalent to 15 min of longitude and latitude, and is covered by portions of the Granite City, Monks Mound, Cahokia, and French Village 7.5-min US Geological Survey quadrangles. Geotechnical parameters of the study area were determined from existing data, including engineering and water well borings, aerial photography, soil, geologic and topographic maps, and published and unpublished reports and field notes. Geotechnical parameters selected for mapping and analysis include physiography, surface geology, subsurface geology, surficial soils, land surface slope, surface drainage, and sources of construction materials. Each parameter, or factor, is portrayed as a transparency for overlay on the map of the dsurface geology, enabling the simultaneous visual analysis of several geotechnical parameters. Of particular importance to engineering projects are the engineering properties of the various surficial soils, mapped by geologic environments and shown on the surface geology map. Relevant engineering properties of soils which occur in abandoned channels, point bars, chutes and bars, backswamps, alluvial fans, tributary valleys, and loessial uplands are given. The occurrence of ground water in the area and its influence on engineering projects is discussed.