ilIAME
DATE
CLASS
STUDYGUIDE
Glociers
Use words in the box to fiII in the blanks.
ICEIN MOTION
15:1 Development
of Glaciers
ice
low
snow
river
three
basal
colder
surges
warmer
plastic
central
weather
valley
outward
glaciers
friction
piedrnont
pressure
Thick masses of ice that move slowly on land are called
'SvtovtJ
forms due to the
c\Oi"rsv't9lct
can move
2
6os-\
or spread
-'rcrtlL*Lr
to retreat, white
flow describes ice layers sliding over one another.
acts as a lubricant to help ice flow over rocks.
conditions affect a glacier.
r'oll€r
V)n"-r*-
$"
"r'A'.r..,
can occur after long periods of little
typeis.. Uo ller"
take over the valleys of a
fi t/ti-
extends onto a plain, u
pl
Ohio Rivers.
temperatures causea glacier
temperaturescausea glacier to ad.vance.
The c.*rln*
moves faster than the edges because of
'-l\anp'a'
. Glacial
in a[ directions from a central location. This
slip occurs when ore [f.^rrt{Ef
Changes irr
l",w
of 30 to 60 meters of overlying snow. GIaciaI ice
movement occurs in two ways.
a gracler
. Glaciers form when more
accumulates than melts and temperatures remain
\Le-
, Iatitudes
downslope
meltwater
continental
North America
|
part of
with the valley walls.
movement. Glaciers are classified as
glaciers, or alpine glaciers,form in high elevations.They
system that existed before glaciation. When a valley glacier
glacier forms. Great masses of ice found in high
NAME
DATE
CLASS
15:2 Erosionby Glaciers
two
horn
soil
open
scour
Ioose
cirque
mounds
deeper
hanging
freezes
plucking
override
headward
abrad,ing
glaciers
V-shaped
waterfalls
As glaciers move over land, they scrape away
. Glacierserodeby
"nr*rlbtr"g
fragments and pile them into massive
*to
methods.
bedrock over which the ice moves.
, and polish long
h€"A,*J
one side
ion5
to the valley. A
l^,"t-
cifQttQ-
it occupies becomes. After the ice melts, outlets
"t
, or basin with
forms when two or more cirques erode a
and become
after glaciers pass through. The thicker a glacier is, the
ha€in\
in cracks,
into underlying bedrock. Valley glaciers erod.e
mountain summit. Valleys eroded by stream action are usually
floor an. r""_
i" the scouring of
These fragments become part of the ice and abrade,
wlhin the valrev.This headward erosion forms u
o??
$-
occurs when meltwater -flneclze-9
expands, and lifts out fragments of
.sco,l,{-
U-shaped
striations
continental
tributaries
Great Lakes
*r;lqkn;u\are
the vaiiey
high above the main valley
d'+Jer1a|19
valleys. When rivers flow in these valler",
roror.
glaciers erode Earth's surface to a greater extent than valley glaciers. They tend to
completely
)ti
6(v+
oL,eniJe-
I,qLe.s
the land, removing
Soi/
and some bedrock. The
were formed in old river valleys by continental
NAME
DATE
CLASS
15:3 GlacialDeposits
sand
tiil
plains
kames
sheet
ketble
gravel
eskers
ground
smooth
melting
outwash
terminal
drumlins
moraine
channels
meltwater
direction
Minnesota's
The first m.aterial dropped as a glacier melts, cailed _
n*It".+€r
, is unsortecl and unlayered.
, flowingaway from the gracier,deposits
sorted and layered debris called
oLc+wa5l1
eot*wa:
. The gently sloping depositsfan out forning large outwasU, Plain4
ges or
Ridges
of rrII
till oeposrled
deposited
ited at
at th.e
/}reltLq
o"elt'n
the margtns
the
margins ot'glaciers
margins
of glaciers
of
when fherfitng
when
slaciers when
l""rrr"
are called
eallerl
occurs are
{rrnn"t itnal moraines.Till droppedfrom the baseof an ice
sl/;!cas melting
as
meltine occurs
occurs
moraine. Ground i? om lra€tendsto
'\)
it is deposited. Ground moraine can form streamlined hills calied
is called
l;.".{i^
icec{i"'"
rl
of the ice flow. Small knobbvtrills of sand and
<tnoo-fl-,
fct*r
lint
I
.r3nr r.e-l
EELe--*
lobes ofice are called
the-land-when-that indicate the
that form between
, long winding ridgds of outwash, are formed
when rivers are created within or beneath the ice and deposit
$c
and gravel within their
riLtun slz:
#.Sma1lbasinsofwater,formedbyblocksoficeme1tingverys1owIy,arecalIed
,
lakes. Most of .
lakes are kettie lakes.
lcEAGES
15:4 Effectsof Glaciation
110
rose
lakes
ocean
rises
stream
weight
Finger
gouged
valleys
glacial
sea level
Evidence ofglaciation other than erosional and
rtO lle7v1
in arid regions and large
lrtb**
-
one such huge lake, Lake B+n&slle
when ice sheets covered
the last ice age,
-l
jffirtrt
Sq
r-brrr:rl features are
lakes
. now occupiedby small streams. As glaciers melted, huge
. Sqlf
eNA+
(r
formed.n.
rebounding
Great Salt
Bonneville
depositionai
t
. fae
F;peer
u
'
Lake,for
"*"-or",
i"
" ""*,'",,t"of
Lakes in New york were formed
-eroded lowlands anrt
''--77- 4e,t/o(4-,
.l
le-p el
i lA
was about
l
the bedrock. During
meters lower than
today. As the glacial ice melted., water returned to the
OcQo-rn
and |he sea level
nO6€. As,the sea ievel rises due to glacial melting, Iand surface
f&eg
also
- -;;1ffi
Thisis dueto
removed.
^
rcku*l
i\of
therandsurface
afber
rh" t,;rl/tt-