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Life Long Learning: Fall 2012
Vagabonds Tramp Eastern AfricaSession One
“Vagabonds Tramp through Eastern Africa: where the unique geology of the East African Rifts produced the advent of the human species and the Nile flood plain
shaped the beginning of human history”
The countries of Africa But first something to ponder
The mind seems to grow giddy by lookingThe mind seems to grow giddy by looking so far into the abyss of timeso far into the abyss of time Jay Playfair, 1805Jay Playfair, 1805
Science:Science:Natural facts discovered by experimentNatural facts discovered by experiment and the testing of hypothesesand the testing of hypotheses 2
Humans are creatures who comprehendHumans are creatures who comprehend things they cannot see andthings they cannot see and believe in things they can not comprehendbelieve in things they can not comprehend William HowellsWilliam Howells
3
What will we find today?What will we find today?
What will we find today?What will we find today? Tales of Narnia: C. S. LewisTales of Narnia: C. S. Lewis
4
The countries of Africa but first a word from Peanuts
May your rock collection never turn to stone!
How to get in touch with us
How to contact us:
Geology & history, Un of Penn paper, http://sino-platonic.org/complete/spp203_geology_human_history.pdf
And now, let’s get ready to tramp the countries of Africa
http://www.ldeo.columbia.edu/video/did-climate-change-shape-human-evolution
Grab your mental climbing gear and let’s scale the heights of Africa
Course Outline
VAGABONDS TRAMP THE EAST AFRICA RIFT ZONE NOVA & SENIOR UNIVERSITY
FALL 2012 Week 1 – Overview
Geology (Don) Geologic overview
- plate tectonics forming Africa - geology & geography of east Africa today
Vagabond travels in east Africa (Sandi) Vagabond life
Living in Luanda Angola & South Africa Overview of traveling in East Africa Statistical comparison (Angola, South Africa, USA)
Week 2 – Rivers Geology (Don)
1st Homo Sapien Sapiens – why east Africa? Influence of rivers/river deltas to emerging civilizations
Developing civilizations – Africa, worldwide (6 early civilizations) Vagabonds in Zimbabwe (Rocky)
Zimbabwe statistics & comparison Huange Nat’l Park (The Hide) Victoria Falls
Zambezi River Week 3 – Savanahs & mountains
Geology: (Don) Geologic processes of mountain building Presence/absence of minerals/metals in east Africa
Vagabonds in Tanzania (Sandi) Tanzania statistics & comparison Mt Kilomanjaro
Lake Mangara Ngorongora Crater Serengeti
Leaky archeological site Week 4 – Lakes
Geology (Don) Influence of minerals/metals/gems on early civilizations (into the Hills)
Vagabonds in Tanzania (Rocky)
Lake Tanganika Searching for Chimpanzees
Week 5 – Great Rift Valley Geology (Don)
Minerals/metals of east Africa today: oil exploration in East Africa Vagabonds in Kenya (Sandi)
Vagabonds Tramp Eastern Africa: Course Outline
The countries of Africa
Course definition of eastern Africa
How does Africa fit in world geology, but first, Geology in the News
The countries of Africa
Geology in the News
News items involving geology from:The New York TimesThe Austin American StatesmanThe Williamson Country SunItems sent to askthegeologist by you
An update on Arctic Drilling
Geology in the NewsFrom the New York Times, June, 24, 2012
Focus on the Chukchi Sea Leases
Did
Interesting trend: each ellipse about equal-distant apart
Focus on the Chukchi Sea Leases & Shell Drilling
Next, the Geology of Northern Alaska, the Chukchi Sea, and Shell Leases
The Geology of Northern Alaska, the Chukchi Sea, and Shell Drill Site (star)
Next, the Geology of Northern Alaska
The Geology of Northern Alaska & Shells Drilling in the Chukchi & Beaufort Seas in the Summer 2012
Next, focus on the geology of the Shell 2012 test well in the Beaufort Sea
Shell test well 2012: Beaufort Sea
Conclusions: Either one of Shell’s wells could find new areas of very large oil & gas reserves but would be very expensive and require new and innovative engineering to get to market.
The latest word on Shell’s 2012 drilling plans
Interior approves Noble drilling rig Discoverer to drill & set surface casing to 1400 feet well above any high pressure zones that might cause a BP-type blow-out.
Shell is waiting on Interior approval of the Arctic Response well control ship Challenger being outfitted in Seattle expected in the Arctic soon.
The Arctic Challenger at the Port of Bellingham in Washington on MondayFailed to meet Federal tests!Now a word from David Brooks of the NY Times
The facts according to DFB are that we are all claiming our entitlements as citizens of the greatest nation on earth by living a lavish life style
that is depleting the vary natural resources that made us the greatest nation. So, in 50 years our grandchildren and great grandchildren
will inherit depleted natural resources of Iron, Coal, and Petroleum that will be insufficient for them to be living in a world power!!!!
Now on a brighter note: exciting, new educational options
Can’t leave Geology in the Newswithout going to the Arctic Sea ice
1979
2002
Arctic Sea Ice Melting
What do you see that’s unexpected?
Using the scientific method
The Scientific MethodThe Scientific Method Good Old Common SenseGood Old Common Sense
1. Observe and Record Information2. Imagine an Explanation(s)3. Test our Explanation(s)
Now back to the Arctic Sea Ice Melting
4. Peers review our Conclusion(s)
Arctic Ocean Ownership Areas
Russia has more then all the others of us combined!!
Oh, yes, back to the Arctic Sea Ice melting
Arctic Sea Ice melting
What do you see that’s unexpected?
What ice mass is this?
And the answer is this? Greenland
Last, from Sunday’s Statesman.
China continues to try to find oil & gas reserves
Eagle Ford shale fracking
Eagle Ford shale fracking
A word or two on possible geology field trips
Eagle Ford Gas & Oil Shale Fracking
The “M” Countries of Africa
Remember the “M” countries in Africa: Morocco, Mauritania, Mali, Mozambique, Madagascar, & Mauritius
Another view
Eastern Africa
The “M” Countries of Africa
Can you find the “M” countries?How does Africa fit in the global pattern of the earth’s rocky crustal plates?
Crustal Plates: Both Oceanic & Continental
OceanicOceanicCombinationCombination
CombinationCombination CombinationCombination
CombinationCombination
What rocks comprise the earth’s rocky crust?
Indian plate under Asian plate = mountain building
The Earth’s rocky crust is broken into the major plates shown here
A Model of the Solid Earth
The Earth’sRocky Crust
Continental Crust
Oceanic Crust
5 miles thick
20 to 50 Miles thick
Focus on Africa
Continental Crust
Continental Crust
Continental
Crust
Oceanic Crust
Oceanic Crust
Oce
anic
Cru
st
How thick is continental crist
Oceanic crust: one of five amazing geologicaldiscoveries in the last half of the 20th century
Oceanic crust: discovered in the last half of the 20th century
8000
mile
s
4000 miles = radius
How thick isa continent?
Earth Cartoon Cross Section
2000 miles
How thick isa continent?
1000 miles
How thick isa continent?
500 miles
How thick isa continent?
8000
4000
2000
1000500
100 miles thickHow thick isa continent?
Continental crust is one half to one quarter as thick as this orange line
How thick is oceanic crust?About one tenth of the orange line, too thin to show here!
Center of the earth
Equator
West
NorthPole
Africa
How far does Africa extend?
SouthPole
South Africa
Cut the earth in half through the poles
Conclusion: continents are a thin veneer on the surface of our earth
Yet they move as “plates” over the face of the earth through time
The Earth’s Crustal Plates Today
From E. A. Keller, 1996, Environmental GeologyFrom E. A. Keller, 1996, Environmental Geology
PacificPlate
North American Plate
Crustal plates move during geologic time
Plate motion in geologic time: 1. moves continents into different climate zones and2. creates mountains when the plates collide
Eurasian Plate
African Plate
Evidence of plate motion
Recent earthquake
Earthquake Epicenters: 25 years
Focus on Africa
Earthquake Epicenters: 25 years Focus on Africa
Nature and age of oceanic crust
Life Long Learning: Fall 2012
Vagabonds Tramp Eastern AfricaSession Two
“Vagabonds Tramp through Eastern Africa: where the unique geology of the East African Rifts produced the advent of the human species and the Nile flood plain
shaped the beginning of human history”
Where we left the geology last week
““That light we see is burning in my hall.That light we see is burning in my hall.How far that little candle throws his beams!”How far that little candle throws his beams!” Portia, The Merchant of Venice, Act V, Scene 1Portia, The Merchant of Venice, Act V, Scene 1
If you want to travel fast, travel aloneIf you want to travel far, travel together
Come join me, and let’s travel together and see what four geological discoveries made in the last half of the 20th Century
will tell sell us about human history; both past, present, and future
But first, geology in the News
Full page Chevron ad in NYT
Responsible hydro-fracking
Geology in the News
Next, asteroids and meteors in our solar system
Orbits of Asteroids and Comets circling our Sun
Locations of Asteroid & Comet Impacts in the Western Hemisphere
Find the two big ones (red)
Locations of Asteroid & Comet Impacts in the Eastern Hemisphere
Findthe one big one (red)
Amazing Geological Discoveries of the Second Half of the 20th Century
Five Amazing Geological Discoveries of the Second Half of the 20th Century
2. Continental Drift3. Absolute Age Dating4. Paleo-magnetics5. Plate Tectonics
Last week we mentioned the discovery of Oceanic Crust which is one of five amazing geological discoveries in the last half of the
20th century
1. Oceanic Crust
Continental Crust
Co
ntin
ental C
rust
Continental Crust
Oceanic Crust
Mid Ocean “ridge”
African Plate: African Continental crust
plus surrounding oceanic crust
The Earth’s Crustal Plates Today
From E. A. Keller, 1996, Environmental GeologyFrom E. A. Keller, 1996, Environmental Geology
PacificPlate
North American Plate
Crustal plates move during geologic time; Note the red arrows showing plate motion
Eurasian Plate
African Plate
Plates are the drifting entities but paleo-reconstructions showonly the drift of the continents through geologic time. Why?
Present Day
Present Day Plate Drift
Plate Drift: Last 250 million years
Continental Drift:
Last 250 million years“Plate Drift is too complicated to be defined”. Quote: Scotese & Blakey
Present Day
250 million years ago
Note: no plates shown
Note: no plates shown
Note: no plates shown
Plates shown
Conclusion: Plate drift is yet to be worked out. We’ll have to work with continental crust drift maps
until plate drift is defined
Now a second amazing geological discoveryof the second half of the 20th Century:
Absolute Age Dating of Rocks
Focus on Africa
Ages of Oceanic Crust: Gray – Continental Crust
Red = modern: Orange, Yellow, & Green progressively older Blue = 250 million years ago
African Plate: Age of Oceanic Crust Red = modern: Blue = oldest 250 million years ago
What process creates the different ages of oceanic crust?
New oceanic crust is constantly being formed by molten rock extruded in the deep oceans along the oceanic ridgesoceanic ridges
A cross section view
Ocean 3 miles deep
New Oceanic Crust being formed
Old Oceanic Crust being destroyed (melted)
Notice the convection cells in the mantle
Another view
Ocean 3 miles deep
Mantle Convection Cells Moving Crustal Plates
Heated
CooledCooled
Mantle convection cells in 3-D
Complex Shape of Mantle Convection Cells
Can you find Africa in the top panel?
Crustal Plates & Mantle Convection Cells
Oceanic Crust
Continental Crust
What is a fourth amazing geological discovery in the second half of the 20th century?
Ocean
Plate tectonics; a.k.a. plate deformation
Plate tectonics; a.k.a. continental crust deformation
Types:Mountain buildingWarpingUp “swelling” over a hot spot
Plate tectonics affecting Africa; a.k.a. continental crust deformation
Mountain building
Warping
Up ‘swelling”
East AfricanRift valleys & the advent of humans
Two additional amazing geological developments in the 2nd halfof the 20th century brought geology from largely a descriptive to a quantitative science like Biology, Chemistry, & Physics
The New Quantitative Geology of the 21st Century
3-D digital reflection geophysics defines theconfiguration and fluid content of the
subsurface rocks prior to drilling
Deep oil exploration drilling finds thick rock layers that have resulted in widespread mountain building for the last 2 billion years
And, this is leading to an appreciation of how the geology of the rocky crust
has shaped human history for the last 50,000,000 years
Let’s summarize what we’ll be discussing in detail in our next 4 sessions
Summary of what we’ll be discussing in detail in our next 4 sessions
Continental Drift positions the continents so that the platetectonic warping of the Northern Temperate Zone of Eurasia
is the unique location for the creation of the 6 earliest civilizations
NileNile
IndusIndus
From: Hammond Atlas, 1972From: Hammond Atlas, 1972
GangesGanges
YellowYellowYangtze Yangtze
Tigris Tigris Euphrates Euphrates
Nile Nile
The six Early Major Civilizations: In the Six Major River Flood Plains located in the southern half of the Northern Temperate Climate Zone
What we’ll try to get you to believe in the next 4 weeks
Tropics
Northern Temperate Zone
Southern Temperate Zone
What we’ll try to get you to believe in the next 5 weeks
First Empires (farming major river flood plains)
Green hills lands with Fe and Coal (invade farming lands)
Conclusions on what is required for a land to become a world power1. Continental drift and plate tectonic put Eurasia in the ideal
location for early farming empires2. Plate tectonics (mountain building) exposed Fe and Coal in
hill lands initiating conflict with farming empires (except in China)3. No world powers or sustainable religions have or will be
developed in the tropics or the southern in the sourthern temperate zone
Now it’s time to apply what we’ve learned to a country we’ll visit in Eastern Africa
