what is crustal extension and which global landscape features does it give rise to?
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WHAT IS CRUSTAL EXTENSION AND WHICH GLOBAL LANDSCAPE FEATURES DOES IT GIVE RISE TO?. CRUSTAL EXTENSION. Crust. Astheno - sphere. Upper Mantle. CRUSTAL EXTENSION. CRUSTAL EXTENSION. Crustal Thinning. CRUSTAL EXTENSION. Crustal Thinning. CRUSTAL EXTENSION. Crustal Thinning. Crustal - PowerPoint PPT PresentationTRANSCRIPT
WHAT IS CRUSTAL EXTENSION AND WHICH GLOBAL LANDSCAPE FEATURES DOES IT GIVE
RISE TO?
CRUSTAL EXTENSION
CrustAstheno-sphereUpper
Mantle
CRUSTAL EXTENSION
CRUSTAL EXTENSION
CrustalThinning
CRUSTAL EXTENSION
CrustalThinning
CRUSTAL EXTENSION
CrustalThinning
CrustalFaulting
DIVERGENCE. 1
Old Crustal Block
DIVERGENCE. 2
Block 1 Block 2CrustalThinning &Faulting
Large reservoir ofliquid magma closeto surface of crust
DIVERGENCE. 2
Active VolcanoesLong DeepLakes
Block 1 Block 2
DIVERGENCE. 3
Block 1 Block 2
Crustal blocks moving further apart
DIVERGENCE. 3
Block 1 Block 2
Crustal blocks moving further apart
Older volcanic rocks cooled, solidifies, contracts and adheres to blocks.
DIVERGENCE. 3
Block 1 Block 2
Crustal blocks moving further apart
Active volcanicity still connected to reservoir in upper mantle
Older volcanic rocks cooled, solidifies, contracts and adheres to blocks.
DIVERGENCE. 3
Block 1 Block 2
Crustal blocks moving further apart
Older volcanic rocks cooled, solidifies, contracts and adheres to blocks.
Active volcanicity still connected to reservoir in upper mantle.
Sea invades long narrow inlet.
DIVERGENCE. 4
Block 1 Block 2
Crustal blocks moving further apart
DIVERGENCE. 4
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
DIVERGENCE. 4
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Younger volcanic further from block.
DIVERGENCE. 4
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Younger volcanic further from block.
Active volcanicity still connected to reservoir in upper mantle
DIVERGENCE. 4
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Younger volcanic further from block.
Active volcanicity still connected to reservoir in upper mantle
Sea broadening, shallow water, volcanic islands in middle
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Old volcanic further from block.
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Old volcanic further from block.
Young volcanic near mid-ocean.
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Old volcanic further from block.
Young volcanic near mid-ocean.
Active volcanicity in mid-ocean.
DIVERGENCE. 5
Block 1 Block 2
Crustal blocks moving further apart
Oldest volcanic rocks near edge of block.
Old volcanic further from block.
Young volcanic near mid-ocean.
Active volcanicity in mid-ocean.
Large ocean basin underlain by volcanic rocks symmetrically distributed
Block 1 Block 2
EAST AFRICAN RIFT VALLEY
Goma, Democratic Republic of Congo
Rwanda
EAST AFRICAN RIFT VALLEY
1
23
4
5
5 HIGHEST PEAKSIN AFRICA
EAST AFRICAN RIFT VALLEY
1
23
4
5
2nd and 3rd DEEPESTLAKES IN THEWORLD
THE WORLD'S 10 LARGEST LAKES
Volume of Lake (km3)
0 5000 10000 15000 20000 25000
Dep
th (
m)
0
250
500
750
1000
1250
1500
1750
2000Average DepthMaximum DepthHighest Point in Florida
MaxMeanVolAreaContinentNameDepth (m)depth (m)(km3)(Km2)
1741730.22300031500AsiaBaikal1435574.51890032900AfricaTanganyika406193.51600082680North AmericaSuperior706250.0772530900AfricaMalawi28180.6468058100North AmericaMichigan29959.9358059800North AmericaHuron9239.1270069000AfricaVictoria
23690.0171019000North AmericaOntario15639.3107027200North AmericaGreat Slave13733.4101030200North AmericaGreat Bear
Bai
lkal
Tan
gany
ika
Sup
erio
rMal
aw
i
Hur
on
Mic
higa
n
Vic
toria
Ont
ario
Gre
at B
ear
and
Gre
at S
lave
GLOBAL DISTRIBUTION OF EARTHQUAKES
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GLOBAL DISTRIBUTION OFVOLCANOES
Block 1 Block 2
Saudi Arabia, Egypt, Sudan and Eritrea, fit together like pieces of a jig-saw puzzle across either side of the Red Sea.
03.00.a1f
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Block 1 Block 2
Volcanic lavas have filled the rift on the African side (Afar Triangle), creating strategic choke-point between Somalia and Yemen!
USS Cole17 Died39 InjuredAden, 2000 Former Yemeni
President, Ali Abdullah Saleh
Extinct volcano!
Block 1 Block 2
Suez Canal links Mediterranean and Indian Ocean via the Red Sea.
Grandfather, Fred Mundy D.C.M.
Suez – Jerusalem 1917-18
Aden: British controlled 1839-
1967.
GLOBAL DISTRIBUTION OF EARTHQUAKES
03.02.b1
GLOBAL DISTRIBUTION OFVOLCANOES
Pre-1967 Arab-Israeli War border of Israel
THE WEST BANKSETTLEMENTS
Jerusalem
GOLAN HEIGHTS (EAST BANK!)
ATLANTIC OCEAN
ATLANTIC OCEANICELAND
ATLANTIC OCEAN
RonaldReagan
MargaretThatcher
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BRITAIN EUROPENORTH SEA
ARGENTINA
FALKLANDSMALVINAS
SOUTHATLANTIC
OIL AND NATURAL GAS
ATLANTIC OCEAN
ST. HELENA
ELBA
GLOBAL DISTRIBUTION OF EARTHQUAKES
03.02.b1
GLOBAL DISTRIBUTION OFVOLCANOES
NB. THESEMUST APPEAR ABOVE SEA LEVEL TO BE PLOTTED!
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ATLANTIC OCEAN
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INDIAN OCEAN
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PACIFIC OCEAN
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SOUTHERN OCEAN
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THINK! TIME AND SPACE.
I II III IV V
FIVE ACT PLAY
Length of Play = 2 hr
7 version of the play running over a period of 4 hrs
SEVEN THEATERS START THE PLAY AT RANDOM TIMES.
SEVEN SPECTACTORS ARRIVE AT EACH ONE OF THE DIFFERENT THEATERS SIMULTANEOUSLY AND RECORD WHICH ACT THE
PLAY IS IN.
One in Act 1, 1 Act 2, 2 Act3, 2 Act 4, 1 Act 5 -: Roughly proportional to the lengthsof time spent in each act.
We can’t watch the whole play (ocean basin formation), but we can visit many oceanbasins now and assume that they represent the lengths of time that the play would spendin each act if we were able to observe it over time.