7. Sedimentary Environments 3.pdf

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Glacial

Glacial processes

processes and

and landforms

landforms

Glacial

Glacial processes

processes and

and landforms

landforms

www.swisseduc.ch/glaciers/earth_icy_planet/icons-02/07-cirque.jpg

Skoltbre

cirque glacie

rs, Norwa

y

Na

tur

al c

auses

Solar output and variations

Plate tectonics and volcanism

Changing

Changing climates

climates and

and

Changing

Changing climates

climates and

and glaciation

glaciation

Orbital variations

Ocean variability

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Milankovitch cycles and climate

Pleistocene

Pleistocene glaciation

glaciation

Research has shown that the 100,000-yr eccentricity cycle is the dominant

facto r in the 100,000-year ice age cyc les of the Quaternary glaciation over

the last few million years.

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments upload.wikimedia.org/wikipedia/commons/7/7e/Milankovitch_Variations.png

Pleistocene ice age

Quaternary glaciation; current ice age; ice age

period of t he last few mill ion years (2.58 Ma to present) in whic h

permanent ice s heets were established in Antarctica and perhaps

Pleistocene

Pleistocene glaciation

glaciation

Greenland, and fluctuating ice sheets have occurred elsewhere

Last Glacial Maximum (LGM)

refers to a period in the Earth's climate history when ice sheets were at

their maximum extension, between 26,500 and 19,000–20,000 years ago,

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Current ic e age

Quaternary/Pleistocene glaciation; current ice age; ice age

Pleistocene

Pleistocene glaciation

glaciation

Backwards Glacial

Names

Inter/Glacial Period (ka) MIS Epoch Alpine N. American N. European Great Britain S. American

n ex

Flandrian interglacial present –₁₂ 1 Holocene

1st _Würm _Wisconsin Weichselian

or Vistulian Dev en si an L la nq ui hu e g lac ia l p er io d 12 – 11 0 2-4 & 5a-d

Pleistocene Riss-Würm Sangamonian Eemian Ipswichian Valdivia interglacial 110 – 1 30 _{(7, 9?)}5e

2nd _Riss _Illinoian _Saalian Wolstonian or

Gipping Santa María glacial period 130 – 2 00 6 i l i lli i l i i i l i l 200 –

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments

i l- i - lli i l i i i l i l

300/380 3rd_{– 5}th _Mindel _{Pre-Illinoian} _Elsterian _Anglian _{Río Llico} _{glacial period(s)} 300/380 –

455 12

Günz-Mindel Pre-Illinoian Cromerian interglacial(s) 455 – 620 13-15 7th _Günz _{Pre-Illinoian} _Menapian _Beestonian _Caracol _{glacial period} _{620 – 680} ₁₆

water frozen into the solid state: snowfl akes, hail, icicles, glaciers, pack

ice, and entire polar ic e caps

???

large masses of ic e formed of compressed snow that move slowl y under

their own w eight; largest reservoir of fr eshwater on Earth

a large piece of ice from fr eshwater that has broken off f rom a snow

-a form of precipit-ation w ithin the E-arth's -atmosphere in the form of

crystalline water ice

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Glacial environments

Glacial processes

Glacial erosio n

abrasion/scouring, pluck ing, ice thrust ing, and glacially-induced spalling

crushing and scouring of surface rocks and bedrock as the glaciers

expand due to their accumulating weight of snow and ice

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Erosional

Erosional features

features

Striations/grooves

scratches or gouges cut int o bedrock by proc ess of glacial abrasion

occur as multipl e straight, parallel grooves representing the movement of

the sediment-loaded base of the glacier

Kelleys Island, USA (OH)

120 m L, 11 m W, 3 m H

Mount Rainier National Park, USA (WA)

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments upload.wikimedia.org/wikipedia/commons/d/db/Glacial_grooves.

jpg en.wikipedia.org/wiki/File:Glacial_striation_21149.JPG

Erosional

Erosional landforms

landforms

Cirque/corrie

an amphitheatre-like valley head, formed at the head of a valley glacier

shape: open on the downhill sid e corresponding t o the flatter area of the

stage, whil e the cupped seating secti on is generally steep cliff-like slo pes

Abi sk o Nati on al Par k, Sw eden

down wh ich ice and glaciated debris comb ine and converge

en.wikipedia.org/wiki/File:Glacial_Tarn_Formation_EN.svg

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Erosional

Erosional landforms

landforms

Tarn

a mountain lake or pool , formed in a cirq ue excavated by a glacier

Tarn Shelf Australia

,

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments en.wikipedia.org/wiki/File:Tarn_Shelf_Mt_Field_National_Park_

2.jpg

en.wikipedia.org/wiki/File:Thornton_Lakes_25929.JPG

Erosional

Erosional landforms

landforms

Glacial ho rn / Pyramidal peak

a mountaintop that has been modif ied by the action of ice during

glaciation and frost weathering

Matterhorn, Switzerland and Italy

Mt. Kinabalu, Malaysia

en.wikipedia.org/wiki/File:Zermatt_and_Matterhorn.jpg

www.cohp.org/personal/southeast_asia/images/Kinabalu/IMGP 3989_50.jpg

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Erosional

Erosional landforms

landforms

Arête

French: ‘

edge

or

ridge’

a thin, almost kn ife-like ridge of rock which is typically form ed when two

glaciers erode parallel U-shaped valleys

Crib Goch , Wales

Garden Wall, USA (MT)

en.wikipedia.org/wiki/File:Crib_Goch,_Snowdonia,_Wales_- _August_2007.jpg

en.wikipedia.org/wiki/File:Garden_Wall.jpg

Erosional

Erosional landforms

landforms

U-shaped g lacial valleys

a depression wi th predominant extent in one direction

Yosemite Valley, USA (CA)

Tracy Arm , Alaska

en.wikipedia.org/wiki/File:1_yosemite_valley_tunnel_view_2010 .JPG

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Glacial processes

Glacial deposition

glaciers retreat and leave behind their freight of cr ushed rock and sand

(glacial drift )

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments en.wikipedia.org/wiki/File:Receding_glacier-en.svg

Depositional landforms

Moraine

any glacially formed accumulation of unc onsolidated glacial debris (soil

and rock ) that may have been plucked of f a valley floor as a glacier

advanced or it may have fallen off t he valley w alls as a result o f fros t

wedging or landslide

Gorner Glacier, Switzerland

en.wikipedia.org/wiki/File:Glacier.zermatt.arp.750pix.jpg elearning.stkc.go.th/lms/html/earth_science/LOcanada3/307/i

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lateral moraine

Vadret da Tschi erva, Switzerland

ground moraine

Múlajökull, Iceland

www.swisseduc.ch/glaciers/glossary/icons/lateral-moraine-tschierva.jpg geoinfo.amu.edu.pl/wpk/geos/geo_9/geo_images_G-15/FigG-15.1.jpeg

terminal moraine

Bylot Island, Canada

medial moraine

Kaskawul sh Glacier, Canada

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments nsidc.org/glaciers/gallery/images/bylot_island_valley_large.jpg nsidc.org/glaciers/gallery/images/bylot_island_valley_large.jpg

Moraine

any glacially formed accumulation of unc onsolidated glacial debris (soil

and rock ) that may have been plucked of f a valley floor as a glacier

advanced or it may have fallen off t he valley w alls as a result o f fros t

wedging or landslide

Depositional landforms

recessional moraine

Garibaldi Provincial Park, British Columbia

supraglacial moraine

vss.sd22.bc.ca/hpp/courses/geo12/course_material/unit5/U05L0

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www.geography-Drumlin

Irish

droimnín

‘little ridge’

an elongated whale-shaped hill whose long axis is parallel wit h the

movement of the ice

Depositional landforms

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.landforms.eu/Lothian/images/drumlin.jpg www.technologyreview.com/blog/arxiv/files/39205/Drumlin.jpg

Esker

a long windi ng ridge of s tratified sand and gravel that are frequently

several km long and are somewhat like railroad embankments

probably former si tes of s ub-glacial str eams and rivers

Depositional landforms

www.dmr.nd.gov/ndgs/ndnotes/Eskers/images/esker%20formed %20copy.jpg www.brianwhittaker.com/Photo-of-Week/Archive/05-12-26-Esker/Esker-26Dec2005-800-www-BrianWhittaker-com.jpg

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Kame

an irregularly shaped hill o r mound c omposed of sand, gravel and till that

accumulates in a depression on a retreating glacier (moulin), and is then

deposited on the land surface with fur ther melting of t he glacier

Depositional landforms

Camelback K ame Glacial Park, USA (IL)

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments www.littledippers.com/geocaching/Kame2.gif

ih1.redbubble.net/work.5564418.1.flat,550x550,075,f.camelbac k-kame-glacial-park-richmond-illinois.jpg

Glacial erratic s

Latin

errare

a piece of roc k that dif fers from th e size and type of rock n ative to the

area in whic h it rests

Depositional features

Big Rock , Canada

15,000 mt

Yeager Roc k, USA (WA)

en.wikipedia.org/wiki/File:Bigrock.jpg

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Outwash fan

a fan-shaped body of sediments deposit ed by braided streams from a

melting glacier

usually poorl y sort ed due to the short dis tance traveled before being

Depositional landforms

Rendu Glacier, Alaska

deposited

Ak ti neq Glac ier, Can ada

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments pubs.usgs.gov/of/2004/1216/no/images/outwashplain1.gif www.prairie.illinois.edu/shilts/gallery/images/shilts-0012_hr.jpg

Kettle / Kettlehole / Pothole

a shallow, sediment-filled body of water formed by retreating gl aciers or

draining floodw aters

result of block s of ic e calving f rom the front of a receding glacier and

Glacial movement

Pothole Lakes, Siberia

becoming partially to wholly buried by glacial outwash

Isunngua highland, Greenland

en.wikipedia.org/wiki/File:PotholeLakes.Siberia.L7.200 10910.jpg

64.19.142.13/upload.wikimedia.org/wikipedia/commons/thumb/c/cb/Kettl e-glacial-lake-form-isunngua-greenland.jpg/800px-Kettle-glacial-lake-form-isunngua-greenland.jpg

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???

A) Kett les

B) Drumlin

C) Outwash

D) Braided Stream

E) Recession al

Moraine

Kettles

Drumlin

Esker

End moraine

Recessional moraine

Glacial

Lake

F) Outw ash Plain

G) Esker

H) Glacial Lake

I) End Moraine

N. Ramos | Geology 11 Principles of Geology Lecture Notes: Sedimentary Environments highered.mcgraw-hill.com/sites/dl/free/0072402466/30425/Fig_1228.jpg

Outwash

Braided stream

Outwash Plain