Glossary Terms Flashcards
A fan shaped deposit of alluvium, laid down by a stream where it emerges from an upland to less steeply sloping terrain
alluvial fan
Material such as clay, silt, sand and gravel deposited by modern rivers and streams
alluvium
A unit layer, 1 cm or more thick, that is visually or physically more or less distinctly separable from other layers above and below in a stratified sequence
bed
The solid rock that underlies the soil and the regolith, or that is exposed at the surface
bedrock
Soil containing sufficient calcium carbonate, often with magnesium carbonate, to effervesce visibly with cold 0.1N (10%) hydrochloric acid
calcareous soil
A zone of essentially saturated soil just above the water table. The size distribution of the pores determines its extent
capillary fringe
As a particle size term: a size fraction less than 0.002mm in equivalent diameter
clay
Containing large amounts of clay, or having properties similar to those of clay
clayey
A substance in a state of fine subdivision, whose particles are 10(-4) to 10(-7) in diameter
colloid
The resistance of a material to deformation or rupture
consistence
The gradual reduction in volume of a soil mass resulting from an increase in compressive stress
consolidation
Slow mass movement of soil and soil material down rather steep slopes primarily under the influence of gravity, but aided by saturation with water and by alternate freezing and thawing. In engineering: general slow displacement under load
creep
The force required to crush a mass of dry soil, or conversely the resistance of a mass of dry soil to crushing
crushing strength
To separate the individual components of compound particles by chemical or physical means or both. To cause the particles of the dispersed phase of a colloidal system to become suspended in the dispersion medium
deflocculate
A fan shaped area at the mouth of a river formed by deposition of successive layers of sediment brought down from the land and spread out on the bottom of a basin. Where the stream current reaches quiet water, the bulk of the coarser load is dropped and the diner material is carried farther out. Recognized by nearly horizontal beds termed bottomset, overlain by more steeply inclined and coarser textured beds called foreset beds
delta
material left in a new position by a natural transporting agent such as water, wind, ice or gravity or by the activity of man
deposit
An elongate or oval hill of glacial drift, commonly glacial till, deposited by glacier ice and having its long axis parallel to the direction of ice movement
drumlin
Wind-built ridges and hills of sand formed in the same manner as snowdrifts. They are startwater, ed by come obstruction, such as a bush, boulder, or fence that causes an eddy or thwarts the sand laden wind. Once begun they offer further resistance and they grow to form various shapes
dunes
sand or silt or both deposited by the wind
eolian deposit
The wearing away of the land surface b running water, wind, ice or other geological agents including such processes as gravitational creep. Detachment and movement of soil or rock by water, wind, ice or gravity
erosion
A transported rock fragment different from the bedrock where it lies. The term is generally applied to fragments transported by glacier ice or by floating ice
erratic
A winding ridge of irregularly stratified sand, gravel, and cobbles deposited under the ice by a rapidly flowing glacial stream
esker
A term used in soil mechanics for the portion of a soil finer than a number 200 US. standard sieve
fines
A term describing the consistence of a moist soil that offers distinctly noticeable resistance to crushing, but can be crushed with moderate pressure between the thumb and forefinger
firm
The land bordering a stream, built up of sediments from overflow of the stream and subject to inundation when the stream is at flood stage
flood plain
All sediments, past and present, deposited by flowing water, including glaciofluvial deposits. Wave worked deposits and deposits resulting from sheet erosion and mass wasting are not included
fluvial deposits
A consistence term pertaining to the ease of crumbling soils
friable
Freezing and thawing of moisture in materials and the resultant effects on these materials and on the structures of which they are a part of with which they are in contact
frost action
The raising of a surface caused by ice and glacial meltwater or rafted by icebergs. This term includes till, stratified drift and scattered rock fragments
glacial drift
Unstratified glacial drift deposited directly by ice and consisting of clay, sand and gravel and boulders intermingled in any proportion
glacial till