Document 94570

Patternsin Natural
Systems:Rivers
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E X P E C T A T I O N S
o identify major river systemsof the world and describe their
drainagepatternsas either dendriticor trellis
r identify patternsin physicalgeography,usingthematic maps
r draw cross-sectional
diagramsof river profiles
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Gatewaysto the Continents
ivers are one of the most important physical features
because they play a huge role in shaping our world.
Rivers have cut channels between mountains, created
deep gorges,and flooded large areasof land. Rivershave
provided us with food, transportation, and sourcesof fresh water.
Rivers influence the land use around them. and are continually changing the landscape.
The St. Lawrence River played a vital role in
66
are part
the settlement of Canada. By following the St.
,Riuers
liaes and our
Lawrence and continuing througn ,niG.".,
,^^-^,,o!our
heritase.
Thet are the threads
, r
,'::'r: il',llT; ,"'?r1lr,l'r]""'
wereaDrero
Many large cities are located or
that bind1he
Tiurtcof natureand
humanity together; that make
canadi, canad'ian''2
For example,winnipeg,Montru"t,ri"ltlirll."
London, ind Moscow were all built on the banks
Parkscanada
of rivers.
Look at the map on page 243.
Each continent has at least
one major river.
J.o".
B r o a ds, h a l l o wc h a n n e l
Narrow,deepchannel
C HAPT
E R 8 : Patterns in Natural S\sterns:Riaers
RiverProfile
{:"g
The water in a river seemsto flow continuously,
but it has a beginning and an ending. The
source, or headwaters,is the location where the
river begins. This is usually a series of underground springs or melting glaciers. Most of the
water in a river comes from surface runoff due
to rain or snow. In some areas, springs bring
groundwater to the surface, and this water too
is added to the river.
$*et Flla
On Morch 29,1848
the enormousomount
of woter fhot flows
over NiogoroFolls
every secondwos
reducedto o mere
trickle. This wosnot
an engineeringfeot,
but o noturolevent
cousedbyhugeice
flows thst blockedthe
flow of Loke'Eriainto
the NioguroRiver.
Riversmay havemore
t h a n o n e s o u r c eS. m a l l
s t r e a m cs a l l e dt r i b u t a r i e s
flow into progressively
l a r g e rs t r e a m su n t i l a
river is formed.
f l o w i n t ot h e
nel of a river
tributaries.
S e m i c i r c u l ca hr a n n e l
U N IT
2:
I ' a . l | e r n si n l ' l t l t i r u l O u t s r a f l t y
a
Watcr drains fi-om tl're highcst point o{'l:rrrcl
in an arca to the lolvcst. I{ivers llorv fronr ther
hieh grotrnd to thc lorv. Vrtr c:rn see ()n :l
map, like the onc on this page, that t'ivcr-s
flow in difl'crent" dircctions. Sonrc flor'
north, while others fkrw south. Thc height of'
land that diviclcs two dif ferent
drainage systems clr drainage basins
ancl sends one rirrel or-re way ancl ,t^uu
the othcr in a cliIl'ercnt clirection is ;
knowrr as thc divide. The Oak
Ridges Moraine, just north of' Torotrto,
cliviclcs trvo clrzrinagebzrsins.This moraine is
the height of land betlveerr rivers that clrain
north to Lake Simcoe ancl rivers that dr:rin
south to Lake Orttario.
a.-:'
Click on lllustrationof Earth's
Sur{acenear the bottom of the
screen.Write down any words that appear
in the diagramthat you don't know.Look
rhem up to discovertheir meaning.
Now visit
.
.. :::: :."::..!.ra.:::: , :
- a
a n d c l i c ko n 3 - D
lmagesandAnimationnearthe bottom
of the page.Click on 3-D Animation.
ChooseOak RidgesMoraine3-D
Animationon the left side of the screen.
C l i c k V i d e of o r W i n d o w s o r Q u i c k T i m e
Movie.Sit back and enioy a simulated
flightover this moraine.
Midland
O a k R i d g e sM o r a i n e
0rillia.
.WasagaBeach
Barrie.
Lindsay
.Peterborough
.
0memee
.
l\ewmarKel
.
Tottenham
a
Aurora
a
a
0 r an g e v i l l e
.Bolton
. .Oshawa
?. whitby
AJax
Toronto
N
H am i l t o n .
Trenton
-#:=
-1i
a
. B r i gh t o n
. R i c h m o n dH i l l
. Burlington
;.',,
Uxbrid
' qe
.
.port perry
.Stouffville
. K i n qC i t v
o 0akville
Campbellford
a
a
Port Cobourg
Hope
a
Colborne
C HAPT
Riaers
E R 8 : Patterns in Natural Systems:
The Great Divide
.rtArrac,
One of the most well-known heights of land in i -e
North America is the Great Divide. On one side of zl1'this divide, the water drains north to the
Arctic Ocean, or east to the Atlantic Ocean, and on
the other side water drains west to the Pacific Ocean.
Why do you supposethat
geographers
describethis
d i v i d ea st h e
drainage
GreatDivide?
Faet Fll*
On CutbonkPossin
GlacierNotionol Pork
lhere ore lhree
streomsso close
together thot you con
pour woter into oll
three ot the some
time. Onestreom will
carry the woter to
HudsonBoy.onother
to the Pocific Oceon,
ond the third to the
Gulf af Mexico.
66 Cross high lands
Where utaters diuide
Tbfarazuay ocea.ns
And trails of days gone by
We're following the stars zaith a
paddle in our hands
,2
Let's see Canada hy canoe.
Canadaby Canoe
Whipper
Music:DavidWhipper/Haze
Whipper
Lyrics:Kirk Whipper/Haze
?d.
A RoyalFlushin Saskatoon
an ugly
noticed
in 1988,people
Oueen
Elizabeth
ll wasto visitSaskatoon
bouta weekbefore
River exactly
of the mightySaskatchewan
brownpatchof waterflowingdownthe middle
wherethe Oueenwouldbe passing.
the hotelwherethe
discovered
that the oldestand mostfamoushotelin Saskatoon,
Citvofficials
quickly,
the city
Very
River.
wasflushingrawsewageinto the Saskatchewan
Oueenwouldbe staying,
visitthe hotelwashooked
streetswereclosedoff, diggingbegan,andjust hoursbeforethe Oueen's
up to the city'ssewersystem.
U N I T 2:
Patterns in Physiral Ckog'aph1
Major tiver Systemsof the World
Every continent has several major river systems - the main
channel of a river and all of the tributaries that flow into it.
These rivers drain large areas of land, and are the focal points of
many communities. Each of the major river systems takes water
that runs off from a continent and drains into one of the oceans.
See the map of Rivers of the World in the Map Appendix, on
page 243.
SuperlativeRivers
u*n^';,Zli;.fl-,:':;',L[Ji;ffi;f#,'nilf
"]';;]"fl'ff;J
\'--rro$t{Ecrro"
-o
c;
before emptying into the Mediterranean Sea. Although the
Amazon River in South America is not as lons as the Nile River,
it drains the largestarea of land in the world. The Amazon River
is 6570 km in length, and drains more
than 6 million km, of South
America' some geographers
t{istory
Fola r1no,
trme,Africawasknown
have estimated that there
as rheDork L'ontinentto
Europeans
are 15 000 tributaries feedbecause
theyknewso littleaboutit. Evenin the middle1800s,
the
into the Amazon' The
sourceof the Nilewasunknownto European
geographers.
n gntish
1ng
Amazon contains one-fifth
missronary,
Dr.DavidLivingstone,
undertook
to find it. Hewent
of the world's fresh wateq
exploring
andforseveralyears
nobodyin Britainheardfrom him
and is so vast that ocean
A searchpartywassentout underthe leadership
of Henry
liners can travel two-thirds
MortonStanley,
who did find Livingstone,
in 1871.At that
of its course'
momenr,
rneyweretheonlyEuropean
people
in that part
o f A f r i c aW
. h e nS t a n l eayp p r o a c h eLdi v i n g s t o n e ,
h es a r d" D r .L i v i n g s t o nI ep,r e s u m eT. h" i s
greeting
hasbecome
famous.
i
T h eNi l e v al l e yan d t h e
N i l ed e l t ar a n ka m o n gt h e
w o r l d ' sm o s tf e r t i l e
f a r m i n ga r e a sS. i n c el 9 6 8 ,
t h o u g h ,E g y p t i a fna r m e r s
a r e u s i n gm o r ea r t i f i c i a l
f e r t i l i z e rosn t h e i rs o i l .U s e
a n e n c y c l o p e dti oa f i n d
o u t w h y t h e y n o w h a v et o
do this.
C HAPT
Riaers
E R 8, Patternsin Natural Systems:
TheColoradoRiverflows
t h r o u g ht h e G r a n d
Canyon.Why do you
t h i n k r i v e r sa r e
such
considered
i m p o r t a np
t hysical
features?
www.infoplease.com
Click on Wodd, then Geography,
'
then PrincipalRiversof theWorld.
;
Which rivers in their list match
'
the ones in your list from question 2 in
1l
the Check Back on this page?Why do , i:
you think there is a differencebetween
their list and yours?
.
,1,
# i i
:r:,,:.r::::::i.tt:'jfai:::::::r:rlr:!:
i.li;.i.iil::it:1i:1ii'irl::i:'l'
North American Rivers
North America has many important river systems. The St.
Lawrence River is a major Canadian commercial transportation
route. In western Canada, the Fraser River is famous for its volume, power of wateq and rugged scenery.The Mississippi is the
longest river (3779 km) in the United States,and drains almost
all of the plains between the Rockies and the Appalachian
Mountains. The Colorado River in Arizona, U.S., is famous for
the Grand Canyon and the Hoover Dam.
' t - r r r - - - l
-
<
#w-* 4
* u*#*g*
r
Baclg
e
1 . 0 n a no u t l i n m
e a po f t h ew o r l dd, r a wa n dl a b et lh em a j orri v e r s oena c h
^^._!:.^^.^!
I
I
youcomptete
FindI
thischart.
America
onpase24etohetp
,. ;::il:t;ap of North
I
fromeach
continent.
Include
rivers
andinclude
10laroe
rivers.
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U N f T
2:
l \ r l l t ' r t t si t t l ' l t y t i r t r l( ; u i ! ) u l ) l t \
I { i r c r s v s t c l r ) sl i r r r n t ' < l r r r l t l c x
' ( I] t l r c
t ) l l 1 t ( ' l ' r r( s) l l l h ( ' s u l ' [ ' 2 r (O
oal'th. ,\nr livcl is r'onlirrrrallv
rlltrkiltg its c'trlvt:slurgcr'.()tr thc slip-off
s l o p e o l ' l l r c r - i v c r ,r r u r l c : r ' i lils r l c l t o s i l r : r l .
()rr thc cut-off slope, thr t'ru-r-t:nt\\'ciu's
'l'lris
t l r c l r : r r r k: u v l r r ' .
l t ' s r r l l si n t l r r ' ( u l \ ( '
i r t c ' r ' t ' u s i ni rgr -s i z t ' .( ) r c r ' l i r n c . i l ' t l r t ' r ' i r c r '
r':rllcl is n'irlc ()n()ugll.lrrrut' lool)s, ()r'
meanders. r':tn [irrrrr.
T l t c ' s t 't n c ' : r r r r l t : ro-Ist c r r l t c c o r r t ' s ( ' l ) : l 'fhc
r:rtcrl {i'orrr Ihe' r'ivcr'.
rivcr' llous
? r ( ' l ' ( ) sl lsr t ' n a l r o u , s l t ' i l l o l ' l a r t r l l r t l l r t '
b : t s co l t h c n r c u n c l c r 'l .r r r r lc r c r r t r r i r l l rl h t '
n r c l r r r c l t 'its' t r r 1o [ ' [ ' ( l ' o r nl l t c r r c u ,( - ( ) l lsr ( '
'fhis
('r'orrl('u
s n ('n('l()s()(l
ol' llrt' r'ivcr'.
pir:r:r'oI u,alcr ctrllcrl an oxbow lake.
Waterwantst o g o s t r a i g h t
a n d h i t st h i s bank.Theflow of
water erodest h e b a n k
Cut-off..slope \
Wateris calmerhere,
so sedimentfallsto
the trottom
Flow
,direction
Sli p-off slope
Bluff
/,
R i r e l s n i l h u p c l r b l c c l b e d : r n c lb a n k
()llcn firt-tnsorncthing r:ullcrl lr braided
pattern. llr':ritlcrl rivers lravc rrurrrvsnr:rll
i s l : r n c l st l r i r t s p l i t t h t ' l l o u , o l w a t ( ) l 'i l t t ( )
'I'hcsc
sc\'o|alS1r('runs.
s t r o a r n s( ) l - ( ' 1 l l u l n e l s : r r - t : . j o i r t c;rrlr r crl l i v i r l c c ls ( ' \ ' ( ' l - :tlilr r r c s ,
I i r r r r r i n g: t b r i r i r l c r l l ) l r t t ( ) l ' n .
River
.-
Sedimenl
Erosion
..
S c d i n r c nbtu id s u p
Neck
S l i p r o f fs l o p e
C u t - o f fs l o p e
' ,//
/
/
....-?el1?i.iii':
O x b o wl ak e
C H APT E R 8,
Rians
Patterns in Natural Systerns:
DrainagePatterns
There are different types of river drainage patterns, that is, the
pattern formed by all the tributaries that feed into the main
channel. The drainage pattern is affected by the underlying rock
- the rock beneath the earth that the river flows over. Different
types of rock erode at different rates. Soft rock (e.g., limestone)
erodes more easily and faster than hard rock (e.g., granite).
.i:... t\1(
l
q/6ll
,l
u-far
t
oYTll
{w
DendriticDrainagePattern
Most rivers have a dendritic drainage pattern. Imagine a leaf. All
the veins connect to the main vein in the centre of the leaf.
Think of the main vein as being the main channel of the river,
and the small veins as being the tributaries. Tributaries join the
main branch of the river in a V-shapedjunction. The V points
downstream. Dendritic drainage patterns usually
occur in gently sloping areaswhere all the underlying rock is about the same hardness so that it
erodes or wears away in a uniform manner. Most
of the rivers that drain into Lake Ontario have a
dendritic drainage pattern.
TrellisDrainagePattern
Some rivers have a trellis drainage pattern, that is,
a rectangular pattern where the tributaries flow
perpendicular to the main branch of the river.
These tributaries are very often located where
there are bands or rows of hard rock and soft rock.
Tributaries travel along the areas that erode faster
(softer rock) and break through the hard rock
where they can.
Trellis
Drainage
Pattern
Theseare two commonriver
patterns.Canyou think of another
patternthat riversmay have?Hint:
Thinkabout the St. LawrenceRiver.
* r : r
c,h*clt
BacI*
I : r r l
pattern.
I
drainage
1. Drawa picture
of a riverthathasa trellis
pattern
of
drainage
page
the
252.
Describe
on
I
2. Lookat themapof SouthAmerica
theAmazon
River.
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- - - J
U N I T 2t
Patterns in Phlsical Gngraphy
Understanding
Concepts
Research
and Communication
Skills
Q In yourownwords,definetheseterms:
a) source
of a river
b) mainchannel
c) tributary
d) mouthof a river
the AmazonRiver,
or the Mississippi
@ Locate
River,
in the MapAppendix
or the NileRiver,
at
the backof thisbook.Discover
andname:
a) its source
b) its length
c) its mouth
d) the important
citieson the river
e) Giveoneinteresting
fact aboutthe river.
fl Drawa sketchmapof the river.
howa meander
iscreated.
Include
a
@ Explain
labelled
diagram
in youranswer.
a wordwebfor all the thingsrelatedto
@ Create
a river.Startwith the wordRIVER
in the centre.
finda map(a roadmapwould
@ In yourlibrary,
begood)of a rivernearor in yourcommunity.
Sketchthisriver,andlabelyoursketchusing
the correctterms.
@ Usean atlasto find the ten longestriversin the
world.
a) Listthemin orderof length.
b) Givethe direction
eachflowsin.
c) Nameonemajorcity eachriverpasses
through,
or near.
@ Visitthe Websitewwwga.usgs.gov/edul
andclickon Menufor all Earth's
mearth.html
Thenclickon Rivers
WaterTopics.
andStreams.
Readthissectionandreporttwo factsbackto
yourclassthat youfoundaboutrivers.
C HAPT
E R 8 z Patternsin Natural S\stems:Riuns
&tapasidGl*be Skills
&pp*ax*&a*xz*
ffi a) Usingan atlas,listten majorriversin
ffi Createa posterthat illustratesthe many ways
w e u s er i v e r sT. h i n ka b o u t l e i s u r ea c t i v i t i e s ,
and other uses.
industry,food, transportation,
G i v ey o u r p o s t e ra t i t l e t h a t t e l l sh o w i m p o r t a n t
flversare to us.
S
Canada.
b ) S o r tt h e s er i v e r si n t o t w o c a t e g o r i e sh:i g h u s ea n d l o w - u s eE
. x p l a i nh o w y o u d e c i d e d
w h i c hc a t e g o r yt o c h o o s e .
Lookat the sketchbelow.
a ) N a m ee a c hf e a t u r et h a t i s s h o w nw i t h a n
a r r o wa n d a l e t t e r .
b ) W h a t i s t h e d r a i n a g ep a t t e r no f t h e r i v e r
that flows throughSouthCity?EastCity?
c) Namethe sourceof South River,EastRiver,
a n d M o o nR i v e r .
d ) N a m et h e l o c a t i o no f t h e m o u t ho f e a c h
river.
Tours
s} You'vebeenhiredby GlobalRiverAdventure
to designa brochurefor their upcomingadventure tour.Youcanchoosethe river.Makethe
ng.
brochure inviting, exciting,and interesti
dangers,
Includemaps,placesof interest,
activities,
that will givethe potentialclients
and pleasures
i n f o r m a t i oann dw i l l m a k et h e mw a n tt o s i g nu p .
!
it
EastCity
.,.{,rrt
M i q h Moraine
T h eH i g hH i l l s
*--S
f
/!,+e-lt.
_p
Health
Springs
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