Glacial Landform

1. Evidence for GlaciersEvidence for Glaciers
ErraticsErratics
StriationsStriations
Polished BedrockPolished Bedrock

2. Erratic

3. ErraticErratic
 Boulder-sized rockBoulder-sized rock
dumped by adumped by a
glacierglacier
 Rock is differentRock is different
type thantype than
surrounding rockssurrounding rocks

5. Striations

6. Striations/ Chatter marksStriations/ Chatter marks
 Grooves carvedGrooves carved
into bedrockinto bedrock
 Formed byFormed by
abrasive action ofabrasive action of
cobbles andcobbles and
pebbles carried atpebbles carried at
bottom of glacierbottom of glacier
 Direction ofDirection of
scratches showsscratches shows
direction glacierdirection glacier
movedmoved

7. Glacial polishGlacial polish
 Smooth rockSmooth rock
surfacessurfaces
 Created as glaciersCreated as glaciers
flow over bedrockflow over bedrock

8. Glacial Pavement….Glacial Pavement….

9. Luis María Benítez.

10. Source unknown

11. ZONE
OF
ACCUMULATION
ZONE
OF
ABLATION
The Upper Grindelwald Glacier and the Schreckhorn,
in the Bernese Oberland, Switzerland.
Adrian Pingstone

12. crevassecrevasse
ss
A great fissure orA great fissure or
crack in a glacier.crack in a glacier.
 They can be more than 30 m deepThey can be more than 30 m deep

13. The Perito-Moreno Glacier, Argentina
TOP LAYER OF GLACIER
CAN FRACTURE…..BRITTLE BEHAVIOR
FROMS CREVASSES
http://www.chmouel.com/geeklog/gallery/gallery_individual.php/argentina/8.html

14. Original valley
(V-shaped)
Glaciers come
and alter
landforms
Glaciers retreat
and new
features appear

16. Landscape Features-Landscape Features-
Valley GlaciersValley Glaciers
 CIRQUESCIRQUES::
 semi-circular shaped bedrock featuresemi-circular shaped bedrock feature
 created as a glacier scours back toward the mountaincreated as a glacier scours back toward the mountain

17.  ARÊTESARÊTES::
steep-sided, sharp-edged bedrock ridgesteep-sided, sharp-edged bedrock ridge
 formed by two glaciers eroding awayformed by two glaciers eroding away
on opposite sides of a ridgeon opposite sides of a ridge

18. CIRQUE
TARN
TARNS:TARNS:
glacial lakesglacial lakes
produced by glacial scouringproduced by glacial scouring
often found in cirquesoften found in cirques

19.  HORNSHORNS::
 3 or more cirques adjacent to one3 or more cirques adjacent to one
anotheranother

20. Hanging Valley

21. ARÊTE CIRQUE
HANGING
VALLEY
U-SHAPED
VALLEY

22. U-shaped valley

23. tilltill
Unsorted andUnsorted and
unstratified rockunstratified rock
material depositedmaterial deposited
dirtectly by glacialdirtectly by glacial
ice.ice.
 Landforms made fromLandforms made from
glacial till are calledglacial till are called
moraines.moraines.

24. Glacial till sediment, in
some places hundreds
of feet thick, covers
most of New York
State.
24

25. All the ‘stuff’ that’s pushed out of the way by the
glacier gets piled up in a big heap, called moraine.
Terminal moraine
Lateral moraine
Medial moraine

27. Lateral moraine
Dirk Beyer

28. Lateral moraine

29. Image by Michael
Medial MoraineMedial Moraine
MorainesMoraines
ChugachChugach
Mountains,Mountains,
AlaskaAlaska
Image by Bruce
Molnia, Terra
Photographics

32.  MORAINESMORAINES: material left behind: material left behind
when glacier recedeswhen glacier recedes

33. Kettle Lake
Till
Drumlins
Terminal Moraine
Glacial
Stream
Moraine-dammed
lake
Outwash plain
Esker

34. Drumlin

35. drumlins

36. Kettle Lakes

37. eskeresker
A long,A long,
winding ridgewinding ridge
formed whenformed when
sand andsand and
gravel fillgravel fill
meltwatermeltwater
tunnelstunnels
beneath abeneath a
glacier.glacier.

38. Eskers

39. kamekame A small, cone-A small, cone-
shaped hill ofshaped hill of
stratified sandstratified sand
and graveland gravel
formed at aformed at a
glacial front byglacial front by
meltwatermeltwater
carryingcarrying
sediment offsediment off
the glacier’sthe glacier’s
surface.surface.

40. http://www.env.duke.edu/eos/geo41/gla2.htm
KAME (WISCONSIN)
Have sorted sediments

41. outwashoutwash
When aWhen a
glacierglacier
melts,melts,
its rockits rock
loadload
remainsremains
in nearlyin nearly
thethe
samesame
place asplace as
in thein the
glacier.glacier.

42. Outwash plainOutwash plain
An outwashAn outwash
plain will beplain will be
crossed bycrossed by
manymany
meltwatermeltwater
streams.streams.