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What is the hydrologic cycle?
A process water follows
through the atmosphere,
biosphere, geosphere and
hydrosphere.
What are the 3 main parts of
the hydrologic cycle?
1. Precipitation: liquid water falling from
atmosphere onto geosphere or
hydrosphere
2. Condensation: gaseous water that
enters the atmosphere and is converted
to liquid water
3. Evaporation: liquid water from the
geosphere or hydrosphere that is
converted to gaseous water in the
atmosphere
Describe the LOCAL &
GLOBAL water budgets.
Local water budget: not in
balance (evap. vs. precip)
Global water budget: balanced
How do rivers & streams form?
1. Small rivulets of water gather
together to form mountain
streams.
2. These will gather together to
create a larger stream called a
river.
Describe the differences
between a youthful and oldage river.
YOUTHFUL
OLD AGE
STEEP
GRADIENT
LOW … ALMOST FLAT
LOW
DISCHARGE
GREAT
FEW, IF ANY
# of TRIBUTARIES
MANY
NONE
(straight stream)
MEANDERS
MANY
NONE
OXBOW LAKES
SEVERAL POSSIBLE
Name and describe the 3 types
of stream load.
1. Dissolved load – particles too
small to see
2. Suspended load – particles of
small sediment, can be seen as
cloudy water
3. Bed load – larger particles such
as small pebbles or rocks that are
carried along the bottom
What is a rejuvenated river:
A river that has a new steeper
gradient as a result of faulting
or folding. (returns to a
youthful stream)
What is a delta?
A place where the river
deposits its sediment load into
a larger body of water.
What is an alluvial fan?
Where a stream deposits its
load onto land as that stream
comes out of a mountainous
area and onto flatter land.
When does flooding occur?
When rain waters exceed the
ability of the land to absorb
the excess water.
What are spring floods?
Floods caused by melting
snow and ice
How do humans try to control
floods?
We build dams to control the
flow of water downstream.
What are meanders?
Bends in the river’s path
downstream
Where along a meander is the
greatest erosion?
Where is the greatest
deposition?
Greatest erosion:
outside edge of curve
Greatest deposition:
inside edge of curve
What is an oxbow lake and
HOW does it form?
Oxbow lake
– part of the
meander
that gets cut
off from the
rest of the
stream by
erosion
What is groundwater?
Water that is located below
the surface
What is an aquifer?
Water that is stored below
ground in the pore spaces
between rocks and sediments.
What is porosity?
Refers to how much water that
sediment can hold in its pore
spaces (the spaces between
the particles)
What is permeability?
This refers to the ability of
water to flow through the rock
layers & sediments
What is the zone of aeration?
The area underground where
the pore spaces are filled with
air.
What is the zone of
saturation?
The area below ground where
the pore spaces are
filled/saturated with water.
What is the water table?
Water that is contained in the
uppermost region of the zone
of saturation
What is the difference
between a well and a spring?
Well – water is pumped from the
ground
Spring – water naturally flows from
below ground onto the surface
(formed when the water table
intersects with the surface of the
land)
What is the difference
between an ordinary well and
an artesian well?
Ordinary well – water must be
pumped from the water table to the
surface
Artesian well – water is held under
pressure (cap rock above) and once
that pressure is released (with a
well), the water flows freely up to
the surface
What is a cone of depression?
The small funnel shape caused
by the rapid withdrawal of
water from the water table
THE
END