Weathering And Erosion

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Abrasion

Back 1

form of mechanical weathering that occurs whenever one rock hits another.

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Chemical weathering

Back 2

form of weathering which decomposes rock; minerals that form at high temperatures and pressures change to minerals that are stable at the Earth’s surface.

Front 3

Ice wedging

Back 3

form of mechanical weathering that occurs as water expands as it freezes, wedging apart rock.

Front 4

Leaching

Back 4

process of removing dissolved minerals as they are carried to lower layers in soil.

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Mechanical weathering:

Back 5

form of weathering which disintegrates rock; bigger pieces of rock are broken into smaller pieces of the same composition as the original rock.

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Deciduous trees

Back 6

trees that lose their leaves once a year.
Humus: partially decayed remains of plants and animals; forms the organic portion of soil.

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Laterite

Back 7

nutrient poor, red, tropical soil which forms in a region with rainforest vegetation

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Loam

Back 8

soil texture which forms from a roughly equal combination of sand, silt and clay

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Pedalfer

Back 9

fertile, dark soil which forms in mid latitude, forested regions.

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Pedocal

Back 10

slightly less fertile soils which forms in drier, grassland regions.

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Permeable

Back 11

describes soil, rock, or other object which allows water to move through it easily.

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Residual soil

Back 12

soil that forms from the bedrock upon which it resides or lies.

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Soil horizon

Back 13

individual layer of a complete soil profile; examples include A, B & C horizons.

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Soil profile

Back 14

the entire set of soil layers or horizons for a particular soil.

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Subsoil

Back 15

the B horizon of a soil; the zone where iron oxides and clay minerals accumulate.

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Topsoil

Back 16

the A horizon of a soil; most fertile layer of soil where humus, plant roots, and living organisms are found.

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Transported soil

Back 17

soil formed from components transported by water, wind or ice to a different area.

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Alluvial fan

Back 18

curved top, fan shaped deposit of coarse sediments that forms when a stream suddenly meets flat ground.

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Base level

Back 19

elevation at which a river meets standing water; a stream cannot erode below this level.

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Bed load

Back 20

the largest particles moved by wind or water; move by rolling or bumping along the ground.

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Competence

Back 21

measure of the largest particle a stream can carry.

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Dissolved load

Back 22

Minerals carried in a solution by the stream.

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Floodplain

Back 23

broad, flat lying plain surrounding a stream channel; created by the stream.

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Gradient

Back 24

slope of a stream or hill or any other feature.

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Groundwater

Back 25

water that moves through pore spaces and fractures in soil and rock.

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Meander

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a bend or curve in a stream channel.

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Natural levees

Back 27

coarse grained deposits of sediments that build up along a stream’s banks as it floods.

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Sinkhole

Back 28

circular hole in the ground that forms as the roof of a cave collapses.

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Stalactite

Back 29

an icicle like formation of calcium carbonate that forms as saturated water drips from the ceiling of a cave.

Front 30

Stalagmite

Back 30

rounded, cone shaped formation of calcium carbonate that forms in caves as water drips onto the floor.

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Suspended load

Back 31

solid particles that are carried in the water of a stream or in the air by winds.

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Barrier island

Back 32

long, narrow island, usually composed of sand that serves as nature’s first line of defense against storms.

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Breakwater

Back 33

structure built in the water, parallel to the shore to protect boats or harbor areas from strong waves.

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Groin

Back 34

long, narrow piles of stone or timbers built perpendicular to the shore to trap sand.

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Sea wall

Back 35

structure built along the shore, parallel to the shore, to protect against strong waves.

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Spit

Back 36

long, narrow bar of sand that forms as waves transport sand along shore.

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Wave height

Back 37

the vertical distance from wave crest to wave trough.

Front 38

Deflation

Back 38

The process of wind removing finer grains of silt and clay; causes the ground surface to subside.

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Desert pavement

Back 39

rocky, pebbled surface created as finer silts and clays are removed by wind.

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Desert varnish

Back 40

dark mineral coating that forms on stable, exposed rock surfaces as windborne clays are deposited.

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Loess

Back 41

extremely fine grained, windborne deposit of silts & clays; forms nearly vertical cliffs.

Front 42

Petroglyphs

Back 42

rock carvings formed by cutting into desert varnish of exposed rock surfaces.

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Saltation

Back 43

movement of sand sized particles by rolling, bumping and jumping along the ground surface.

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Sand dune

Back 44

deposit of sand formed in regions of abundant sand and constant winds.

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Ventifacts

Back 45

polished, faceted stones formed by abrasion of sand particles.

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End moraine

Back 46

unsorted pile of glacial till that marks the furthest reach of a glacier’s advance.

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Glacial erratic

Back 47

large boulder with a different rock type or origin from the surrounding bedrock.

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Glacial striations

Back 48

long, parallel scratches carved into underlying bedrock by moving glaciers.

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Horn

Back 49

sharp sided, angular peak formed as glaciers move away from a central peak.

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Kettle lake

Back 50

often circular lake formed in the outwash plain by stranded ice.

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Plucking

Back 51

removal of blocks of underlying bedrock by the glacier as meltwater seeps into cracks & freezes.

Front 52

Rock flour

Back 52

fine sediments produced by abrasion of glaciers scrape over bedrock.

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Varve

Back 53

paired deposit of light colored, coarser sediments and darker, fine grained sediments.

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Avalanche

Back 54

mass of snow that suddenly moves down a mountain under the influence of gravity

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Creep

Back 55

exceptionally slow movement of soil down hill.

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Lahar

Back 56

volcanic mudflow formed when rain or melted snow combines with volcanic ash and dust.

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Landslide

Back 57

rapid movement downslope of rock and debris under the influence of gravity.

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Mudflow

Back 58

saturated soil that can flow very rapidly or slowly down a slope depending on the viscosity of the flow.

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Saturated

Back 59

unable to absorb any additional material: e.g. soil soaked with water, very salty sea water

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Talus slope

Back 60

pile of angular rock fragments formed at the base of a cliff or mountain.