Transcript If water soil it settles to a level called the . As ground saturates the water table rises. If you dig a well below the water.

If water
soil it settles to a level
called the
.
As ground saturates the water table rises.
If you dig a well below
the water table you can
access the water!
If water table rises or falls, surface water
also changes.
Base your answers to questions below
on the diagram, which shows a model
of the water cycle. Letters A through F
represent some processes of the
water cycle. Letter X indicates the top
of the underground zone that is
saturated with water.
Base your answers to questions below
on the diagram, which shows a model
of the water cycle. Letters A through F
represent some processes of the
water cycle. Letter X indicates the top
of the underground zone that is
saturated with water.
Different
ground has
different
porosity.
If water cannot
infiltrate it will
runoff on the
surface.
Porosity
affected by size.
=
Less pores,
but bigger
Porosity
More pores,
but smaller
affected by...
Packing of Grains
More porous
Less porous
Shape of Grains
Flatter sediments are less porous
Mixed Sizes
of Grains
Which beaker has the largest sized pores?
Which beaker can HOLD the most water?
THEY HAVE EQUAL POROSITY!
(more small pores = less big pores)
The diagrams below represent three
containers, A, B, and C, which were filled with
equal volumes of uniformly sorted plastic
beads. Water was poured into each container to
determine porosity and infiltration time.
1. The mixture of sand clay and pebbles holds the most water.
2. The cup of sand holds more water than the cup of silt.
3. All cups hold the same amount of water.
4. The cups of pebbles and silt hold the same volume of water.
Assuming equal amounts of precipitation and
saturation, which soil could rain infiltrate the
most readily?
Greater Porosity = Faster Infiltration
Infiltration depends on
.
Water cannot
infiltrate
saturated
ground, making
.
Infiltration also depends on
.
Desert soil is often impermeable. Even small
amounts of rain will run-off, causing flash
floods.
Only a few seconds have passed!
is related to
.
BUT THEY MEAN DIFFERENT THINGS.
Equal porosity but VERY DIFFERENT
permeability!
As a rule, the slower water
infiltrates, the slower it drains.
Easy in
easy out!
Capillarity
Water is so sticky it can “climb” soil particles,
moving up against gravity.
Larger particles have less capillarity.
Smaller particles have more capillarity.
The diagram represents four identical columns filled with sediments of
uniform shape and packing. They are placed over empty glass beakers.
The diagram represents four identical columns filled with sediments of
uniform shape and packing. They are placed over empty glass beakers.
The diagram represents four identical columns filled with sediments of
uniform shape and packing. They are placed over empty glass beakers.
The diagram shows a laboratory setup. The rubber
band holds filter paper across the base of the open
tube to hold the soil sample. The tube was placed
in the water as shown. The upward movement of
water is represented by arrows.
Results with different size particles
lead to the conclusion that
(1) capillarity is greater in soils
with larger particles
(2) capillarity is greater in soils
with smaller particles
(3) permeability is greater in
soils with larger particles
(4) permeability is greater in
soils with smaller particles