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…
UNIT 9: SURFACE PROCESSES

PACKET 10: WEATHERING, EROSION & DEPOSITION,
LANDSCAPES
Weathering and
Erosion… what’s the
difference anyway?
P.S I’m Ziggy
EARTH SCIENCE
MS. GILL
NOTE PACKET #9
NAME:___________________CLASS:_________ DATE:______
________
Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
Vocabulary:
Abrasion
Agents of erosion
Barrier island
Beaches
Burial
Cemented
Channel shape
Chemical precipitation
Chemical weathering
Compacted
Delta
Density
Deposition
Depositional
Discharge
Drumlins
Dune
Dynamic equilibrium
Erosion
Escarpments
Finger Lakes
Flood
Flood plain
Glaciers
Gradient
Inorganic
Kettle lakes
Landforms
Meander
Moraines
Mountains
Organic
Outwash plain
Parallel scratches
Physical weathering
Plains
Plateaus
Precipitation
Rate
Rate of deposition
Ridges
Sandbars
Sand-blasted bedrock
Slope
Sorted
Static equilibrium
Stream
Stream drainage patterns
Tributaries
Unsorted
U-shaped valleys
Valleys
Velocity
V-shaped valleys
Watershed
Wave action
Weathering
Wind
Zone of breaking waves
Sediments
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
A. Weathering: is
______________________________
______________________________
______________________________
For weathering to occur the rocks must be
exposed to one or more of the following:
1. ______________________________
______________________________
2. ______________________________
______________________________
3. ______________________________
______________________________
Evidence of Weathering:
The end product of the weathering of rocks is
______________________________.
We classify sediments by size:
Use the reference table pg. 6 to complete the chart below
Sediment Name
Range of diameter (cm)
Boulder
Cobble
Pebble
Sand
Silt
Clay
Dissolved particles
Not visible (in solution)
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
Physical Weathering:
Rocks are broken into smaller pieces without changing the ______________________ nature of rock.
Explain how the following can cause physical weathering in the following ways:
* Freezing/thawing of water:________________________________________________________
___________________________________________________________________________________
*Abrasion:___________________________________________________________________________
___________________________________________________________________________________
* Biologic activity: :________________________________________________________
___________________________________________________________________________________
* Human Actions: :________________________________________________________
__________________________________________________________________________________
Chemical Weathering:
Rocks are broken and the chemical composition is ______________________.
Examples of chemical weathering:
 Oxidation:
Occurs when _________________ from air combines with ____________________ to form oxides.
Ex. _________________________________
 Carbonation:
Occurs when _________________containing ___________ acid dissolves minerals.
Ex. __________________________________
 Pollution:
Can speed up the rate of weathering. Oxides of ______________ & _______________ make rainwater
unnaturally acidic.
Ex. __________________________________
 Hydration:
Occurs when ________________ such as mica and
feldspar absorb _____________ and weaken to
form ______________________
Use the grid at right the complete the chart below:
Temp
Precipitation Type of
Weathering
A
5
100
B
20
100
c
-10
50
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Unit 9: Surface Processes
Earth Science- Ms. Gill
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Weathering Rates:
Rate of weathering also depends on:
______________________________________________________
______________________________________________________
If your increase surface area, you will _____________________
the rate of weathering.
Climate Affects Weathering:
Physical weathering dominates in
________________, _________________ climates
Chemical weathering dominates in
________________, _________________ climates
In general when there is more _______________________
there is more weathering.
Soil formation: ______________________________ &_______________________________ (WBA)
Soil sits on top of solid bedrock. Soil is the combination of:
______________________, ________________________, ____________________
The end product of the weathering of rocks and biologic activity is_________________.
Soil Horizons (layers):
_______________________________________________-A
_______________________________________________-B
_______________________________________________-C
The two types of sediment (soil) are:
1. ________________________ : ____________________________________________________
2. ________________________: _____________________________________________________
Soil associations (characteristics): 3 ways that soil can differ in various locations:
1. ________________________________________________________________________________
2. ________________________________________________________________________________
3. ________________________________________________________________________________
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Unit 9: Surface Processes
Earth Science- Ms. Gill
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B. Erosion: is ________________________________________________ and
Depositing them elsewhere.
Erosion is driven by the force of ***______________***
The agents of Erosion are:
 ___________________________
 ___________________________
 ___________________________
Each Agent of Erosion Produces it’s Own Characteristic
Shape and Texture in the sediment and its own unique landscape.
-RUNNING WATER ________________
AND________________ THE ROCK SURFACE
ALSO MAKES IT_______________________
- WIND BLOWN SEDIMENTS _________
AND __________ THE ROCK SURFACE
- SMALL SEDIMENTS IN THE
GLACIER _____________ & ______________
THE ROCK SURFACE, BUT LARGE SEDIMENTS ________________
AND ________________ THE ROCK SURFACE
-GRAVITY FALLS: FALLEN ROCKS ARE
* THE PRIMARY AGENT OF EROSION
_______________& _________________
________________
__________________
C. Deposition: The ______________________ of particles and fragments.
It is also called ________________________________________
Deposition usually occurs under water under the forces of gravity.
The agents of deposition are:
 ________________________________
 ________________________________
 ________________________________
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
Landscape Development:
A landscape refers to the general shape of a region on the Earth’s surface.
The shape of a landscape is also known as its ___________________________
We describe landscape regions in terms of the: Heights of hills, Shapes of hills
Stream patterns, Soil type (rock composition)
LANDSCAPE REGIONS:
Landscape regions can be classified as one of the following:
__________________________, ______________________, _______________________,
____________________________ or ___________________________.
MOUNTAINS: ____________________, ____________________ &______________
HIGH PEAKS AND DEEP VALLEYS
2. IGNEOUS AND METAMORPHIC ROCK
3. STEEP STREAM GRADIENTS
4. STEEP SLOPES
5. FOLDED, FAULTS, TILTED ROCK LAYERS
Plateau
1. FLAT OR ROLLING HILLS
2. DEEP CUT STREAM VALLEYS
3. HORIZONTAL LAYERS OF
SEDIMENTARY ROCK
Plains
1. MOSTLY FLAT- FEW HILLS
2. HORIZONTAL SEDIMENTARY LAYERS
3. MEANDERING STREAMS
Glacial Landscapes
Glaciers deposit _______________________ sediments. Bedrock acted upon by glaciers is generally
polished and ____________________ or striated by sediment in the ice. Glacial valleys are generally
__________ shaped. Other glacial land scape feature include: eskers, kettle lakes, kettle holes,
drumlins and moraines.
Landscapes shaped streams and rivers
Through erosion, a river creates valleys, waterfalls, flood plains, meanders and oxbow lakes. Rivers
often from on mountain slopes due to melting ice caps. There a river generally follows a straight narrow
coarse, creating a deep V-Shaped valley. Lower down a river usually flows over more gently sloping land.
Here the river spreads out, forming a water wide river valley. The flat wide area of land along a river is
a flood plain. A meander is a loop-like bend in the course of a river. Sometimes a meandering river forms
a oxbow lake, a meander that has been cut off from the river. Landscapes shaped by streams and rivers
primarily affected by the action of _________________and ________________. The resistance of
the bedrock beneath the stream or river will dictate the drainage pattern and river shape. Less
resistant rock with weather and eroded faster than more resistant rock, cause areas of low elevation
where rivers and streams will flow. Deposition at the mouths of running results in the formation of
deltas and alluvial fans and the formation of sedimentary rock.
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
See pages 2 & 3 in your ESRT! You have to use them together! They map the same place!
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
Other agents include ___________ &_________driven by the force of _____________
If uplifting forces have been dominant the landscape will be _____________________.
If erosion has been dominant the landscape will be ____________________________
If uplifting and leveling forces are in balance, the landscape is in
______________________________________________________________
The term sedimentary basin is used to refer to any geographical feature exhibiting subsidence and
consequent infilling by sedimentation. As the sediments are buried, they are subjected to increasing
pressure and begin the process of lithification. As more and more sediment is deposited into the basin, the
weight of all the newer sediment may cause the basin to subside further because of isostasy. A basin can
continue having sediment deposited into it, and continue to subside, for long periods of geological time; this
can result in basins many kilometers in thickness. Geologic faults can often occur around the edge of, and
within, the basin, as a result of the ongoing slippage and subsidence
Most of New York State soils are not residual, they are ____________ by ___________
Landscape Development:
Landscape results from the opposing forces of _____________ and _______________
Uplift is often caused by
______________________ ________________________ The
resulting geologic events include __________________, _____________________
_______________ & ___________________ which create _____________________
The most important leveling agent is erosion by ________________ ______________
Notice how the rock types weather differently. -->
Differences in rock resistance creates varied &
interesting landscapes. Which rock is least resistant?
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
The Influence of Climate on Landscape: A change in climate can also create an _____________
___________ which leads to glaciers and glacial landscapes.
Humid (moist)
Arid (dry)
Slope
Soil
Type of
Weathering
The Influence of Humans:
Through the use of ___________________________ humans have been able to alter the shape of
of the land. We can make changes in the landscape in a few months that would take nature hundreds of
years to achieve. It could also take hundreds of years to remedy the __________________________
effects of technology. Environmental planning and conservation can help to preserve our soil, water, and air .
Landscape Review Questions: Use the two New York State Maps on pages 2 and 3 of your Reference Tables
to answer the following questions:
1. Which of the landscape regions occupies the greatest area in New York State? _______________
2. In which landscape region can you find the finger lakes?_________________________
3. In which landscape region can you find Mt. Marcy? __________________________________
4. List 5 cities that are located in the Allegheny Plateau: ______________________________
5. List 3 cities that are located in the Erie-Ontario Lowlands: __________________________
6. Which landscape region is the youngest? ____________________________________
7. What is the distance between Mt. Marcy and Slide Mt. In Miles and Kilometers?_______________
Landscape Region
Geologic time period the
Dominant rock type
Region was formed
(classification)
Erie-Ontario Lowlands
Adirondack Mountains
Tug Hill Plateau
Hudson-Mohawk Lowlands
Newark Lowlands
Atlantic Coastal Plain
Allegheny Plateau
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
AGENT #1 RUNNING WATER: (STREAMS, RIVERS & FLOODS)
PARTICLES ARE CARRIED IN SEVERAL WAYS IN RUNNING WATER DEPENDING ON THEIR
_____________ AND _______________________. THE FASTER THE WATER THE BIGGER THE LOAD
IT CAN CARRY. AS A STREAM OR RIVER SLOWS DOWN IT RELEASES OR DEPOSITS THE PARTICALS
IT CARRIES IN SIZE ORDER, DROPPING LARGER COBBLES FIRST AND SMALLEST PARTICLES LIKE
CLAY LAST.
THREE WAYS STREAMS TRANSPORT SEDIMENT:
 Sediments __________________________________ Examples: Salts and Calcite
 Sediments__________________________________ Examples: Clay and Silt (colloids)

Sediments ____________________________________ Examples: sand, pebbles and cobbles
***SEDIMENTS LEFT BEHIND BY STREAMS AND WIND ARE: ______________
Meaning dropped off in size order
But note that Glacial deposits are unsorted.
WHAT IS THE MINIMUM VELOCITY NEEDED TO CARRY A PEBBLE? ________
WHAT IS THE MINIMUM VELOCITY NEEDED TO CARRY A BOULDER? _______
As a stream slows down from 100 cm/s to .5 cm/s, which list in order which particle will be deposited.
Which particles will stay in suspension?
________________________________________________________________________________
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
DISCHARGE & VELOCITY OF RUNNING WATER
A. Sources of water for streams: ___________________ & _________________
B. In moist climates, streams are fed by _________________ during dry periods.
C. In dry climates, streams lose water to the _____________________.
Factors that determine stream discharge:
A. ___________________
• time lag (between max. rainfall and max. stream
discharge)
• takes time for runoff to reach the stream
B. ____________________
 Increased vegetation blocks overland flow and slows
stream response
C. __________________ or _________________ (same)
• The land from which the water comes, that drains
into the stream
• Large drainage basin more discharge
• Small drainage basin less discharge
D._____________________________
Rapid runoff if …..
• ground is paved
• impermeable (bedrock)
• frozen
Velocity
Runoff: includes all the water that moves over Earth’s surface, and due to gravity run off always moves
downhill. The amount runoff in an area depends on five main factors: amount rain, amount of vegetation, type
of soil, shape of land and how people use the land.
Streams: natural channels which allow water to flow downhill
Discharge: VOLUME OF WATER FLOWING PAST A SPOT IN A GIVEN AMOUNT OF TIME. In other
words the amount of water. The more discharge the faster the stream.
Most runoff gets into streams and as runoff increases, __________________________!
Discharge
THE VELOCITY OF A STREAM DEPENDS ON :

__________________________________________

__________________________________________

_________________________________________
Water moves faster on the _________________ of a bend.
Water moves slower on the _________________ of a bend.
On a straight path the maximum velocity is in the _________
below the ___________
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
EROSIONAL-DEPOSITIONAL SYSTEM:
____________________ or ____________________ are examples of this kind of system.
Within a stream system energy transforms from ________________to _____________ energy
____________________will dominate in the steeper section and
____________________ in places of less gradient or slope.
Kinetic energy depends on _________________ velocity increases,
kinetic energy increases and more erosion occurs.
Potential energy depends on _______________ not slope, energy is stored and depostion occurs.
When the rate of erosion equals the rate of deposition
_______________________
______ __________________ is reached.
Erosion occurs more often on _____________________ and
Deposition occurs in large bodies of _______________________
Streams that flow over ____________ valleys may develop ______________ (bending) paths because
of Erosion and deposition.
*You will have to be able to draw the cross-section of
a stream channel along a curved or straight path.
X
X
Look at the Diagram on the Right 
-Erosion occurs at points
_______ & _______
-Deposition occurs at points ______& ________
Y
Maximum erosion occurs where there is maximum
__________________ as indicated by the shaded area
In each stream cross section.
Y
Z
Z
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
River Landscape development: The maturity of a river depends upon the portion of the land that has
been worn down to or near ______________________ _________________________. This
depends on the bedrock that is beneath the stream.
The 3 stages of landscape maturity ( describe each diagram)
Young:
1.MUCH OF THE LAND AT HIGH ELEVATIONS
2. STEEP HILL SLOPES
3. FAST STREAMS
4. DEEP V-SHAPED VALLEYS
Mature:
1. ROUNDED HILL SLOPES
(IF MOIST CLIMATE)
2. STREAM VALLEYS ARE BROAD
3. STREAMS BEGIN TO MEANDER
Old:
1. MOSTLY ERODED TO BASE LEVEL
2. STREAMS HAVE LOW SLOPE (GRADIENT)
3. STREAMS MOVE SLOW & MEANDER
4. FERTILE AND THICK SOIL HORIZON A
Water Sheds:
All of the land that drains into a particular
river or stream is called a drainage basin or
watershed. Watersheds are divided by high
elevations such as mountain ranges.
A tributary is a stream that flows into a larger stream. A drainage basin is the land area from which a river
and it’s tributaries collect water. A divide is the high ground between two drainage basins.
A stream bank is the land area along
side the river or stream.
Watershed practice questions:
1. An environmental scientist needs to prepare a report on the potential effects that a proposed surface
mine in New York State will have on the watershed where the mine will be located. In which reference
materials will the scientist find the most useful data with which to determine the watershed’s boundaries?
a.
topographic maps
b.
geologic time scales
c.
tectonic plate maps
d.
planetary wind maps
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
4. The photograph below shows a sign
near the Esopus Creek in Kingston,
New York. The main purpose of the
word "watershed" on this sign is to
communicate that the Esopus Creek
a. is a tributary of the Hudson River
b. is a flood hazard where it flows
into the Hudson River
c. forms a delta in the Hudson River
d. contains ancient fish fossils
2.Which lettered section represents the watershed
of the Mohawk and Hudson Rivers?
a. A
b. B
c. C
d. D
3.The pattern of stream drainage shown on the
Watersheds map is influenced most by the
a. structural features of the bedrock
b. differences in soil composition
c. activities of humans
d. temperature of the area
Stream Drainage Patterns
The bedrock of an area will cause streams to drain in a pattern that can be seen from overhead. Theses
are called _______________________ _____________________ the geologic structures below create the
following drainage patterns.
1
2
3
4
1. Which stream drainage pattern above would most likely develop on the surface of a volcano? __________
2. Which map shows the stream drainage pattern that usually develops on the surface of horizontal rock
layers? ___________________
3. Which map shows the stream drainage pattern that develops on a domed mountain?________
4.The diagram below represents a geologic cross section in which no overturning has occurred. The letters
identify specific regions in the cross section. Match the letters to the drainage patterns above, one pattern
is used twice and another is not represented at all.
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Note Packet #10
Deposition by Streams and Rivers:
Deltas and Alluvial Fans
As water moves it carries sediment with it. Anytime moving water slows down, it deposits some of this
sediment. Deposition creates landforms such as alluvial fans and deltas. When a river flows out of a
mountain valley, the water slows and deposits sediments in a fan shaped structure called and alluvial fan.
Horizontal sorting is characteristic of this wide sloping deposit. A river ends when it flows into a still body
of water such as an ocean or lake. There th e water slows downs, also deposition sediment in a horizonatally
sorted pattern. These sediments build up form a delta.
1. Fan-shaped sediments deposits at the mouth of rivers
and called deltas. The Nile, Amazon and Mississippi
rivers have well-developed deltas
2. Alluvial Fans form as the result of sediments being washed
down a mountain.
VELOCITY OF TRANSPORTING MEDIUM:
The slower the velocity of the water the ______________ the particles will settle.
It takes longer for particles to settle in ________________________ water.
SORTING OF SEDIMENTS:
Horizontal sorting: _________________
_______________________________
________________________________
________________________________
RATES OF RIVER AND STREAM DEPOSITION DEPEND ON:
1. Particle size: _____________ particles (clay, silt) settle more slowly than larger particles.
___________ do not settle out of solution unless the solution becomes ___________________.
___________________ & ____________________ are the ions that come out of solution.
2. Particle shape: ___________ between water and the surface of particles ________ settling. As
surface area _____________ the time it takes to settle ________________
3. Particle density: ___________ particles settle faster.
Complete the Graphs Below: Label each axis
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Unit 9: Surface Processes
Earth Science- Ms. Gill
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FLOODING:______________________________________________________
• precipitation rate exceeds infiltration rate
• hurricane- storm surges
• impermeable ground (bedrock, frozen, paved, saturated already)
Flood Plains
1. Flooded sediments build up on the sides of rivers, forming natural levees. The flood plains beyond
them are the most fertile lands in the world.
2. Occasionally, heavy rains over a short period of time cause flash floods. Flooding can occur very
quickly, creating a great deal of property damage.
3. Flooding cause a great deal of erosion and subsequently
Deposits a lot of sediment into a river basin at one time.
4. Vertical Sorting: Results from the deposition
of a large amount of material at once into a body
of water such as a pond, lake or ocean basin.
5. Cross Bedding: _____________________________
________________________________________
Crossbedding result from multiple depostions events.
So the picture to the right represents three flooding events where
The river or stream dumped sediment into a lake bed or ocean basin
Summary: Erosion by running water results in the following landscape features.
1) V-Shaped valleys 2) oxbow lakes 3) meandering rivers 4) sorted particles in layers 5) rounded and
smaller sediments 6) Deltas 7) alluvial fans
Meandering streams
V shaped
valley
Sorted round sediments
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Unit 9: Surface Processes
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Agent #2 WIND:
Erosion by wind occurs
primarily in ___________ climates.
The particles transported (eroded)
by wind are __________________________.
Wind:
Sediments left by wind are ________________.
Sand dunes may form with a gentle slope facing into the wind. ( ______________________)
and a steep slope on the opposite (______________________)
When wind direction changes sand dunes cross each other creating a feature known as
_______________ _____________________.
Most sand dunes are well ___________ in sloping ___________.
The sand grains are
_______________ and ___________________
Deposition on Coastlines by Ocean Waves and Currents:
-Wind influences the direction of ocean waves.
The sand grains are ______________ & _____________ .
________________ generates waves.
Waves more sand ____________________ to the shore.
Barrier beaches may form like Jones beach or Fire Island.
Wave action rounds sediments as a result of ____________.
The long shore current moves sediments parallel to the shore.
Humans put up jetties and groins
to stop erosion on the windward side of the structure.
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Unit 9: Surface Processes
Earth Science- Ms. Gill
Agent #3: Gravity (Erosion by Mass Movements):
Note Packet #10
Movement of loose
earth material down a slope due to gravity
a. Slow movement is called creep.
b. Sudden movements of material are called landslides. They can occur with soil, ice, snow or rock.
c. Clay and Silt that are saturated with water can form mudflows. These can be quite devastated.
Examples: Avalanches and Landslides
The diagrams below represent four different examples of mass movements that
transports sediments due to gravity:
1. Which erosional force acts alone to produce avalanches and landslides?
a.
gravity b.
winds c.
running water d.
sea waves
2. Sharp-edged, irregularly shaped sediment particles found at the base of a rock cliff were probably
transported by
a.
gravity b.
wind
c.
ocean waves
d.
running water
3. The diagram below shows the surface features of a landscape.
Based on the features shown, which erosional agent had the greatest effect on tree growth and the
structures that humans have built on this landscape?
a.
running water
b.
moving ice
c.
prevailing wind
d.
mass movement
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Unit 9: Surface Processes
Earth Science- Ms. Gill
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AGENT #4 GLACIAL EROSION:
When more snow in winter accumulates than ________________ in the summer the snow at the
bottom turns to ____________. If it becomes thick enough, it’s weight will cause it to move under the
pull of ____________________
Characteristics of Glacial Erosion:
1. Glaciers create ______ shaped valleys
2. Sediments left behind by glaciers are ______________ & _____________________
3. Sediments left behind by glaciers are _____________________________
4. Glaciers are like rivers of ice.
Some glacial features include:
U-shaped valleys
Moraines: unsorted sediments
Drumlins: elongated moraines
kettle lakes: round glacial lake
finger lakes: elongated glacial lake
outwash plains: deposited by melt-water streams
Erratic: large rock
deposited by a glacier
Escarpment: steep cliff
Horn: sharp peak
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Unit 9: Surface Processes
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Glaciers:
Sediments left by glaciers are ________________.
Glacial __________________ are large rocks that
have been transported by glacial ice
without being broken into pieces.
Some glacial features include:
1. ________________________
2. ________________________
3. ________________________
4. ________________________
5. ________________________
6. ________________________
7. ________________________
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Unit 9: Surface Processes
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Glacial Landscapes:
The advance and retreat of glacial ice carves and deposits several distinct features in it’s path.
Glacial geologist study these features to gain insight about the direction of ice movement, climate changes,
and the extent of glacial advance. This sheet will serve to look at each feature individually.
Glacial till is very compacted unsorted sediment. Till is deposited directly by the glacier when the
glacier melts away. Glacial till deposits are very resistant to erosion because these deposits were compacted
under the weight of the ice. Some till deposits are found in elongated hills called moraines. Moraines are
made of till (unsorted and un-layered) that accumulated in front of advancing ice, as the ice moved it pushed
this material up in front of it. The location of a moraine signifies where the ice stopped for a period of time
or the furthest extent of glacial advance.
As the ice advances it picks up and incorporates rock particles into the ice. This process is called
plucking. As these sediments are drag along the base of the moving ice, they break down and weather into
smaller pieces, along the way they polish and scratch the bedrock beneath. The scratches left behind are
evidence for the direction of glacial advance and are referred to as striations. Some larger pieces of rock
that become incorporated into the ice make their way to the top of the glacier, here it is protected by the
ice rather than dragged along the bottom. These large pieces can be transported and deposited thousands of
miles from their original location. These boulders are called erratics. Geologist study the composition of
these erratics to determine their geographic region of origin. Larger features also left behind by glaciers
include kettle lakes, eskers and drumlins:
Eskers are long, narrow, steep-sided
ridges of coarse sand and gravel
deposited by a stream flowing under a
melting sheet of glacial ice.
Kettle lakes are formed when
a large boulder sized chunk of ice
becomes buried by sediment. When
the ice melts the water seeps into the
ground leaving a void, resulting in a
topographic depression called a kettle
hole. If the topography of the kettle
hole intersects the water table, then
the hole will have water in it and this is
called a kettle lake.
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Unit 9: Surface Processes
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Drumlins like moraines are also formed of till. They are elongated features that can reach a
kilometer or more in length. One end is quite steep and the other end has a gentle slope. The steeper end
is called the Stoss and faced into the ice flow. The Lee slope is the more gentle slope and points toward
the direction of ice movement. From an areal view drumlins can look like tear drop shapes. It is common to
find several drumlins grouped together. The collection of drumlins is called a swarm. Drumlins are thought
to form under the ice, sediment was pushed up until too much sediment accumulated and the glacier could
no longer push it. Rather the glacier flows over the deposit instead of continuing to push it. The tapering
leeward side is formed as sediment is dragged down slope as the glacier moves over the drumlin.
CROSS-SECTIONAL VIEW
AERIAL VIEW
1. ____________________:
A bed of sorted gravels and deposits
2. _____________________: A long
winding ridge left by a stream that flowed
in an ice tunnel under the glacier.
3. _______________________: water
filled hollow left by a block of ice.
4._______________________: A long
hummocky mound of debris left at the
front of the glacier.
Fill in the blanks on the RIGHT using the
following terms:
-Outwash plain
-Esker
-Kettle Lake
-Terminal Moraine
-Drumlin
-Sorted sands and gravels
5. _______________________: The
long rounded mound of till formed under
the flowing ice and usually occurring in
groups.
6. _______________________: A
fairly flat area beyond the terminal
moraine
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