plain landforms, meander, braided channel, and valley 

 side.) HP 



Valley side (valley wall) — The sloping to very steep surfaces 

 between the valley floor and summits of adjacent up- 

 lands. Well-defined, steep valley sides may be termed 

 "valley walls." Note: Scale, relief, and perspective 

 may require use of closely related terms such as hill- 

 slope, mountain slope, and ridge side. HP 



Valley side alluvium — A concave "slopewash" deposit at 

 the base of a hillslope, mountain slope, terrace escarp- 

 ment, or similar feature, that may or may not include 

 the alluvial toeslope. HP 



Valley train — A long narrow body of glacial outwash 

 confined within a valley below a glacier; it may, or may 

 not, emerge from the valley and join an outwash plain. 

 HP 



Varve — A sedimentary layer, lamina or sequence of 

 laminae, deposited in a body of still water within 1 

 year; specifically, a thin pair of graded glaciolacustrine 

 layers seasonally deposited, usually by meltwater 

 streams, in a glacial lake or other body of still water in 

 front of a glacier. HP 



Volcanic — Pertaining to (1) the deep-seated (igneous) 

 processes by which magma and associated gases rise 

 through the crust and are extruded onto the earth's sur- 

 face and into the atmosphere, and (2) the structures, 

 rocks, and landforms produced. (See extrusive.) HP 



Volcaniclastic — Pertaining to the entire spectrum of 

 fragmental materials with a preponderance of clasts of 

 volcanic origin. The term refers not only to pyroclastic 



materials but also to epiclastic deposits derived from 

 volcanic source areas by normal processes of mass 

 wasting and stream erosion. (Examples are welded tuff 

 and volcanic breccia.) HP 



Wash (dry wash)— The broad, flat-flooded channel of an 

 ephemeral stream, commonly with very steep to ver- 

 tical banks cut in alluvium. Note: When channel reaches 

 intersect zones of ground-water discharge they are 

 more properly classed as "intermittent stream" chan- 

 nels. (Regional term used in the western United States; 

 a synonym is arroyo.) HP 



Wave-built terrace — A gently sloping coastal feature at 

 the seaward or lakeward edge of a wave-cut platform, 

 constructed by sediment brought by rivers or drifted 

 along the shore or across the platform and deposited in 

 the deeper water beyond. GG 



Wave-cut platform — A gently sloping surface produced 

 by wave erosion, extending far into the sea or lake 

 from the base of the wave-cut cliff. It represents both 

 the wave-cut bench and the abrasion platform. GG 



Wave-cut terrace — A synonym for wave-cut platform. GG 



Weathering — All physical and chemical changes produced 

 in rocks or other deposits at or near the earth's surface 

 by atmospheric agents with essentially no transport of 

 the altered material. These changes result in disintegra- 

 tion and decomposition of the material. (See regolith, 

 residuum, and saprolite.) HP 



Wind gap — A former water gap now abandoned by the 

 stream that formed it, suggesting stream piracy or 

 stream diversion. HP 



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