Glacial outwash sand

Fig. 4. Cross section through glacial outwash sands (dotted) along the Connecticut shore (at longitude 72°34 W). Marine mud deposited on the outwash is shown shaded. (Based on data obtained by C. Sullivan, personal communication, 1977.)...

The general character of the surficial sediments in Long Island Sound is known from the published data of Buzas (1965), McCrone et al. (1961), Bokuniewicz et al. (1976), and the reports prepared by Donohue and Tucker (1970), Ali and Feldhausen (1975), and the U. S. National Marine Fisheries Service (1974). The floor of the eastern Sound is composed of reworked, glacial outwash sand, and the sandy bottom is also found along the exposed shoreline. A map of the sand content of the bottom sediments has been prepared by Schubel and Wise (1979) from the published and additional unpublished data. This map (Fig. 2) represents over 400 analyses. 

Potassium is bound rapidly in silicates and adsorbed in day minerals, albeit very loosely in soil organic matter. Most agricultural soils continue to supply potassium for a long time (> 20 years). Potassium appears to be plentiful in most forest soils, but exceptions are add glacial outwash sands, soils vdth a low clay content and skeletal soils, for example, derived from quartzit. Subsoils are almost always low in exchangeable potassium. 

The site is situated on a glacial outwash plain, and surface deposits consist of fill and undisturbed gravel and sand outwash containing minor silt and peat. Underlying the outwash at a depth of 20 or more feet is glacial till. Groundwater occurs under water table conditions within the highly permeable outwash deposits at a depth of 8 to 12 ft across the site. 

The atmosphere, in turn, affects soil development by providing oxygen and by wind erosion and deposition. Sand dunes are only the most obvious example. Loess soils are deposits of silt-sized particles carried by winds from riverbeds and glacial outwash. A large fraction of the clay content of the soils along the eastern shores of the Mediterranean Sea has been carried by winds several thousand kilometers from the Sahara Desert and Atlas Mountains of North Africa. Trade winds carry Saharan clay particles several thousand kilometers out into the Atlantic Ocean. 

Bohlke J. K., Wanty R., Tuttle M., Dehn G., and Landon M. (2002) Denitrification in the recharge area and discharge area of a transient agricultural nitrate plume in a glacial sand outwash aquifer, Minnesota. Water Resour. Res. 38(7), doi 10.1029/2001WR000663. 

Ice (a) Glacial till (moraines, till plains, drumlins, etc.) (b) Fluvio-glacial deposits (eskers, terraces, outwash plains, etc.) Unstratified heterogeneous mixture of boulders, gravel, sand, silt, and clay. Stratified, usually granular. 

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