WEATHERING & EROSION - Heartland Community College
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Transcript WEATHERING & EROSION - Heartland Community College
WEATHERING &
EROSION
Chapter 4
Test 3 material
Begin
ASSIGNMENT
WRITE A 1-2
PAGE REPORT
ON HOW KARST
TOPOGRAPHY
HAS
INFLUENCED
LANDFORMS IN
THE MIDWEST
10 POINTS –
DUE IN 1 WEEK
WEATHERING
PROCESSES BY WHICH ROCKS
ARE CHEMICALLY ALTERED OR
PHYSICALLY BROKEN INTO
FRAGMENTS AS A RESULT OF
EXPOSURE TO THE ELEMENTS
MECHANICAL
WEATHERING
ROCK IS BROKEN INTO
SMALLER AND SMALLER
PIECES EACH RETAINING THE
CHARACTERISTICS OF THE
ORIGINAL MATERIAL
FROST WEDGING-FREEZE/THAW
UNLOADING - SHEETING
BIOLOGICAL ACTIVITY
spheroidal
CHEMICAL
WEATHERING
COMPLEX PROCESSES THAT
ALTER THE INTERNAL
STRUCTURES OF MINERALS BY
REMOVING AND/OR ADDING
ELEMENTS
WATER AND CARBONIC ACID OXIDATION
EROSION
THE
PROCESSES
THAT LOOSEN
SEDIMENT AND
MOVE IT FROM
ONE PLACE TO
ANOTHER
CYCLE OF EROSION
WILLIAM MORRIS DAVIS
YOUTH
MATURITY
OLD AGE
REJUVENATION
FACTORS OF
WEATHERING AND
EROSION
CLIMATE
THE TYPE OF ROCK
THE AMOUNT OF VEGETATION
DIFFERENTIAL
WEATHERING/EROSION
DIFFERENT ROCKS WEATHER &
ERODE AT DIFFERENT RATES
LANDFORM FEATURES
PLATEAUS ERODE TO MESAS
MESAS ERODE TO BUTTES
buttes
DIFFERENTIAL
WEATHERING/EROSION
LIMESTONE BEST
ILLUSTRATES THIS
IN DRY CLIMATES LIMESTONE
PRODUCES MOUNTAINS
IN WET CLIMATES WITH ACIDIC
WATER QUALITY IT PRODUCES
FEATURES OF KARST
TOPOGRAPHY
KARST TOPOGRAPHY
FEATURES
SINKHOLES/DOLINES
STALACTITES
STALAGMITES
COLUMNS
FOUND IN ILLINOIS, MISSOURI,
KENTUCKY, FLORIDA, INDIANA,
YUGOSLAVIA
KARST
SINKHOLE
VIRTUAL CAVE
http://www.goodearthgraphics.c
om/virtcave/virtmap.html
GRADATION
WEARS DOWN AREAS OF
GREAT RELIEF AND BUILDS UP
AREAS OF LOW RELIEF
CHIEF PHYSICAL AGENT OF
GRADATION IS WATER
TIME ALLOWS GRADATIONAL
PROCESSES TO WORK
EQUILIBRIUM
PERFECT BALANCE IN NATURE
THRESHOLD
RESPONSE TIME
RELAXATION TIME
ANGLE OF REPOSE
MAXIMUM ANGLE MATERIAL
STAYS STABLE BEFORE
MOVING DOWNSLOPE
FOR UNCONSOLIDATED
MATERIAL THIS IS BETWEEN 25
TO 40 DEGREES
Angle of repose
MASS WASTING
DOWNSLOPE MOVEMENT OF
ROCK AND SOIL UNDER THE
DIRECT INFLUENCE OF
GRAVITY
GRAVITY IS THE CONTROLLING
FORCE OF MASS WASTING
CLASSES OF MASS
MOVEMENTS
FALL
SLIDE
FLOW
CREEP - MATERIAL MOVED BY
CREEP ACTION IS REFERRED
TO AS COLLUVIUM
FALL
Rock fall
slide
flow
creep
SLUMP
DOWNWARD SLIPPING OF A
MASS OF ROCK OR MATERIAL
MOVING AS A UNIT ALONG A
CURVED SURFACE
slump
WHY SLUMP OCCURS
OVERSTEEPENED - MATERIAL
REMOVED FROM BOTTOM OF
SLOPE
OVERLOADING - LESS
RESISTANT MATERIAL IN
UNDERLYING LAYERS