Eolian sands

Figure 14. The heirarchy of heterogeneity scales for an eolian sand. Permeability groups by the third-order heterogeneity classifications. Our measurements deal primarily with wind ripple, grainflow and intradune groups. (Reproduced from Ref. 5.)...

Kocurek, G. (1991) Interpretation of ancient eolian sand dunes. Annual Review of Earth and Planetary Sciences 19, 43-75. 

Kocurek, G. Dott, Jr. R.H. (1981) Distinction and uses of stratification type in the interpretation of eolian sand. Journal of Sedimentary Petrology 51,... 

Thomas, D.S.G., Bateman, M.D., Merhshahi, D. O Hara, S. (1997) Development and environmental significance of an eolian sand ramp of last glacial age, Central Iran. Quaternary Research 48, 155-161. 

Kerr, R.C. and Nigra, J.O. 1952. Eolian sand control. Bulletin American Association of Petroleum Geologists, 36, 1541-1573. 

Al-Awadi J, Gemak J (1998) Sand traps for measurement of eolian sand drift rate. In Omm SAS, Misak R, Al-Ajmi D (eds) Sustainable development of arid zones assessment, vol 1, pp 177-188... 

Van Mourik, J.M., Wartenbergh, P.E., Mook, W.J. and Streurman, H.J., 1995. Radiocarbon dating of palaeosols in eolian sands. Mededelingen Rijks Geologische Dienst 52, 425-439. 

Loess refers to deposits of fine-grained wind-blown (eolian) sediments, which may accumulate up to 100 m thick. The material mostly consists of silt grains with perhaps 5-30% clay-sized particles and 5-10% sand (Benn and Evans, 1998), 291. Like other sediments, loess may contain considerable arsenic depending on the chemistry of its source rocks (Table 3.15). 

The importance of stratigraphic studies and the identification of sedimentary units at extensively disrupted sites like Hierakonpolis can be illustrated by the excavations at locality II, where there is evidence for habitation (trash mounds and pottery) as well as industry (pottery kilns). This locality ofiered a unique opportunity to study Predynastic ecology because of the excellent state of organic preservation in an area where there was a clustering of multi-functional components (6,14). Four test pits were dug in one area through the site, in the direction NIO °E-SIO °W. The correlation profile is shown in Figure I. The oldest unit identified was Nile silt (Masmas formation). In some areas, this silt was covered by eolian and/or wadi sands, which probably represents a local feature of sand accumulation under arid to semiarid conditions. 

Langford, R.P. (2003) The Holocene history of the White Sands dune field and influences on eolian deflation and playa lakes. Quaternary International 104, 31-39. 

Deposition (aggradational) coasts are the most common type occurring at the southern and eastern margins of the Aral. They are usually low (1.0-1.5 m), and built of loose marine and fluvial deposits (quartz sands with shed debris). The lowest parts are flooded and form channels between the low islets, locally beating eolian dunes. 

Eolian plains (planicies eolicas) plains covered by sand and silt, which were deposited by wind during the Pleistocene in the Llanos, eolian plains with stabilized Pleistocenic dunes more than 10 m high are distinguished from completely flat eolian plains covered by silt strata. These plains extend principally from the southern central Llanos to the lower Arauca-Cinaruco basins in the west Llanos. 

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