Hydrology-How we use our
water!
Condensation
Transpiration
Precipitation
Runoff
Infiltration
Infiltration
Zone of
aeration
Zone of
Saturation
Infiltration occurs when the regolith is:
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

permeable
unsaturated
moderate slope
Runoff occurs when the regolith is:
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

Impermeable
Saturated
Steep gradient
Permeability
The ability of water to flow through.
The speed is the permeability rate.
The opening of the rock material must be
interconnected to allow water to flow through.
Water infiltrates through the zone of aeration until it
reaches the zone of saturation.
The water table is at the top of the zone of saturation.
Impermeable bedrock is below the zone of
saturation.
Porosity
• Is the amount of open space between
particles. It depends on
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–
–
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Shape
Packing
Sorting
Not size
Porosity and Shape
• Rounds have greater porosity or open space
than angular particles.
Angular-very little open
space
Round-more open space
Porosity and Packing
• Tightly packed materials have a lower
porosity.
Loosely packed-high
porosity
Tightly packed-low
porosity
Porosity and sorting
Same size = well sorted (high porosity)
Different size = poorly sorted/unsorted
(low porosity)
Same size = high porosity
Mixed = low
porosity
Porosity and size
• The same shape particles have the same
porosity as long as they are sorted.
Porosity = 30%
Porosity = 30%
Mixed = 10%
Porosity and Permeability
• For water to quickly infiltrate a material
must be porous and permeable
• Aquifer – natural water pipe
Water Retention
Smaller particles retain more water because
smaller particles have more surface area.
Capillarity
Water moving upward through soil.
Smaller holes are better.
• Hydrologic cycle
• Aquifer – artesian well
• Capillary water
Weathering
•
•
•
•
Break down
Preparation for erosion
Smaller the particle=faster
Climate and type of material make a huge
difference in weathering rates.
Physical Weathering
• SMALLER PIECES
– Frost Action
– Abrasion
– Exfoliation
Chemical Weathering
• Smaller BY CHEMICAL CHANGE
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–
–
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Oxidation - oxygen
Hydration - water
Carbonation – carbonic acid (acid rain)
Decay – rot, acid is given off, breaks down
materials
Today
1. Turn in corrected quiz
2. Finish halite shake and finish lab
3. In packet, complete the soil section 2-2
using a Earth’s Changing Surface book.
Take it home if needed.
Soil
• End product of weathering.
• Residual – stays in one spot
• Transported – moved from the original rock
For Monday
• Correct Quiz
• Finish lab
• Look at chart on page 132
In computer lab:
• 1. Finish weathering and erosion scavenger
hunt
• In book, 2-2 (should be done)
• In book, 2-3, Soil Conservation
– Homework if it is not done today!
Surface area and weathering
• http://courses.soil.ncsu.edu/resources/physic
s/texture/soilgeo.swf
•
•
•
•
Starter, graph and questions page 132
Soil and weathering video
10 questions
Homework – Erosion 3-1 with book
Starter
On an index card, answer questions 1-10 on
page 135-137 in your green book.
On your desk, please get out your homework
3-1 Erosion so I can check it.
Today: Erosion/Streamflow lab 3-2 and
stream tables after your notes.
• Erosion
Starter
Video
Lab 3-3
For Thursday:
Water Erosion, using the Earth Changing
Surface Book
Finish lab – including questions
(conclusion)
Starter
• On an index card, answer question 1-10 on
page 141-143. Use your notes!
• Lab from Friday out 3-2
Stream
Down cutting V-shaped valley
Lateral Erosion – flood plain
Youth
•V-Shaped Valley
•Rapids
•Waterfalls
•No Flood Plain
•Drainage Divides Broad and Flat, Undissected by Erosion
•Valley Being Deepened
•General Agreement on this stage, lots of examples
Maturity (Early)
•V-Shaped Valley
•Beginnings of Flood Plain
•Sand and Gravel Bars
•Sharp Divides
•Relief Reaches Maximum
•Valleys stop deepening
•General Agreement on this stage, lots of examples
Maturity (Late)
•Valley has flat bottom
•Narrow Flood Plain
•Divides begin to round off
•Relief diminishes
•Sediment builds up, flood plain widens
•River begins to meander
•Lots of Disagreement from here on; some geologists believe
slopes stay steep but simply retreat.
• Stream evolution
Old Age
;
•Very Wide Flood Plain
•Land worn down to flat surface (Peneplain)
•Resistant rocks form residual hills
(Monadnocks)
•Pronounced River Meanders
•Cut-off Meanders (Ox-bow lakes)
nd (Lowering of Sea Level, sometimes greater stream flow) causes stream to speed up and cut deeper.
m valley takes on youthful characteristics but retains features of older stage
happen at any point in the cycle.
Erosion
Deposition
Meanders
Erosion
Deposition
Cut-off
Cut-off
• Thursday - wrap up of erosion/deposition
notes
• Friday – deposition/stream lab
• Monday – Go over constructed response
• Next Week – Tuesday – Section 1, Surface
Processes Test
Tributaries
Distributaries
Delta – Alluvial fan
All delta deposits
Delta development
Sand Bars – parallel to the shoreline
Colloids
never settle
Big sediment
Small sediment