The document discusses various geological processes related to weathering, erosion, deposition, and topography. It explains that weathering breaks down rock through exposure to air, water or ice, and erosion is the movement of weathered material. Deposition occurs when sediment is dumped in a new location, often at river mouths, and layers build up through compaction over time. Erosion shapes the land through formation of valleys and differential wear. Coastlines are affected by these processes and weather patterns, changing their contours over thousands of years. Topographic maps represent three-dimensional landforms through contour lines of equal elevation.
2. 1. Weathering and Erosion
A. Weathering: exposure to air, water, or ice, causing the
rock to break down chemically and mechanically.
B. Erosion: the movement of weathered material.
C. The "Maltese Cross", a
well-known rock
formation in the
Cedarberg Mountains,
Western Cape Province,
South Africa. These hard
sandstones have been
shaped into tall pillars and
other fantastic forms by
weathering along the
vertical cracks in the rock.
3. 2. Deposition and Compaction
A. Deposition: the dumping of
sediment in a new location by
erosion; often at the mouth of a
river or at some solid structure
that impedes movement (such
as a jetty.
B. Compaction: as layer upon
layer of sediment builds up,
pressure on the lower layers
causes sediment to stick
together and form solid rock.
LAYERS!
ALLUVIAL FAN!
4. 3. Erosion Patterns
A. Solid rock and/or land
begins to erode.
B. Small valleys begin to
form.
C. Some parts wear away
faster than others.
D. After thousands, even
millions, of years,
landforms have altered
dramatically.
5. 4. Coastline Patterns
A. Deposition occurs along
coastlines, often forming
small landmasses called
jettys.
B. The contour of the
coastline often changes
with deposition of new
sediment and erosion of
existing land.
6. 5. Other Affects on Coastlines
A. Coastlines are also affected by weather patterns.
B. Air from the coast blows inland, causing cities on
the coast to be similar to the water temperature
rather than inland counterparts
1. Warm air causes coastal cities to be warmer than the
inland while cold air causes the coastal city to be colder
than the inland..
C. Large landmasses can create currents that travel
up or down coastlines, causing temperature
differences. This is especially obvious on smaller
landmasses, such as islands.
7. 6. Topography
A. Topography: the surface features of an area.
B. This map shows the presence of an island but gives no
clue how tall the island is.
C. Topographic maps are 2 dimensional representations of 3
dimensional landforms.
8. 7. Building a
Topographic
Map
A. Always start at
Sea Level: 0.
B. Select an
interval (on this
map 10 ft).
C. Trace the land
contour at each
interval.
9. 7. Building a
Topographic
Map
D. When done,
you have a
topographic
map.
E. Now you know
how high
some features
are compared
to others.
10. 8. Reading a
Topographic Map
A. Contour lines: points
of equal elevation.
1. Contour lines cannot
cross
B. Contour interval: the
difference in elevation
between 2 lines.
C. Index contour:
elevation lines that are
labeled and usually
darker than others.
D. What is the contour
interval of this map?
1. Hint: pretend it’s a
thermometer.
20 ft
11. 8. Reading a
Topographic
Map
E. What is the interval
of this map?
F. The closer the lines,
the steeper the
landform.
G. The farther away the
lines are, the flatter
the landform.
H. Label the steepest
and flattest parts of
this map.
20 ft
STEEP
STEEP
FLAT
FLAT