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Soil may be regarded as waterlogged when it is nearly saturated with water much of the time such that its air phase is restricted and anaerobic conditions prevail. In extreme cases of prolonged waterlogging, anaerobiosis occurs, the roots of mesophytes suffer, and the subsurface reducing atmosphere leads to such processes as denitrification ...
Patterned Ground – Patterned ground occurs where stones form circles, polygons and stripes. Local topography affects which of these are expressed. A process called frost heaving is responsible for these features. Solifluction lobes – Solifluction lobes are formed when waterlogged soil slips down a slope due to gravity, forming U-shaped lobes.
The definition of the term in geology and paleontology is slightly different from its use in soil science. In geology and paleontology, a paleosol is a former soil preserved by burial underneath either sediments (alluvium or loess) or volcanic deposits (lava flows or volcanic ash), which in the case of older deposits have lithified into rock.
The most distinctive landforms created by gelifluction include gelifluction lobes and gelifluction benches. The former refer to tongue-shaped deposits of geliflucted material orientated downslope that tend to form on slopes of between 10° and 20°, whereas the latter refer to terrace-like deposits forming on gentler slopes with a long axis running parallel to the slope contour.
A flat or very gently sloping area on the floor of a deep ocean basin. absolute dating The process of determining a specific date (in years or some other unit of time) for an archaeological, geological or paleontological site or artifact. accident A sudden discontinuity of ground, such as a fault of great thickness, bed or lentil of unstable ...
The water table may vary due to seasonal changes such as precipitation and evapotranspiration.In undeveloped regions with permeable soils that receive sufficient amounts of precipitation, the water table typically slopes toward rivers that act to drain the groundwater away and release the pressure in the aquifer.
An example was given that this might be a dried-up river channel (known as a palaeochannel), which may subsequently reveal rich waterlogged archaeological deposits in its lower layers, or an area of slightly higher ground above winter flood level on an alluvial floodplain, which may be very hard to detect from the ground but which has attracted ...
The vadose zone does not include the area that is still saturated above the water table, often referred to as the capillary fringe. [ 1 ] Movement of water within the vadose zone is studied within soil physics and hydrology , particularly hydrogeology , and is of importance to agriculture , contaminant transport, and flood control .