who were the first to migrate across the pacific ocean
Why did the polynesian people travel across the pacific ocean
probably for food in canoes
explored area larger than china and soviet union combined
early navigation *
-reflection of islands in clouds
-followed birds - eg. frigate and terns - dusk/dawn pattern
build raft with tradtion sails
made it from Peru in 1947
made it in less time
redid experiment with modern equipment
mediterranean explorers and traders
made it around africa
the world according to herodotus
1st to make map of ocea
-explored coast of England, Norway
-discovered the Atlantic had tides and linked to moon
-librarian at the library of Alexandria - collected ship logs-center for knowledge for Nautical Science
-figured out circumprerences of earth
-use direction and angle of sun
-his value 40,000 km - true 40,032 km
-lots of exploration
-farthest known extent of eurpopean exploration before columbus
-erik the red - sailed west from iceland and discovered greenland
-leif eriksson- son of erik the red - set out to find newfoundland and did named it vinland
-5 ships and 288 sailors return with 1 ship and 18 sailors
-Juan Sebastian del Cano - made it back Magellan didn't
-Prince Henry - The Navigator - School for Mariners
-Bartholomew Diaz - 1488 - Cape of Good Hope - tip of Africa
Three expeditions of Captain James Cook
dates of Captain James Cook's expeditions
What was the importance of Captain James Cook
1st time for systematic exploration of ocean
The cook expedition
-extensive scientific investigations
-arctic to antarctic
-map Pacific Ocean
-depth sounding - rope and weight
-wind and currents
-general geography of the pacific and atlantic
Charles Darwin's boat
importance of Charles Darwin
origin of species - trained naturalsit
when was the US Exploring Expedetions
what was the importance of the US exploring Expedition
explored coast of Antarctica
map of oregon territory
throughly explored hawaii
who was in charge of the US exploring expedition
Lt. Matthew Maury
Lt. Matthew Maury
1st oceanogrphy text book
father of physical oceanography
who lead the challenger expedition
charles wyville tomson
importance of the challenger exedition
made 362 sample/observations at intervals as nearly uniform as possible
what was discovered from the 362 sample/observations on the challenger expedition
bottom tempurature recorded
life couldn't exist below a certain depth of the ocean
The challenger and the azoics theory
133 dredges - 4700 new species of animals
william beebe and otis barton
take long cores
learn about water column
Satellites can tell us
Chl (a measure of plant productivity)
1596 - Abraham Ortelius
could be joined
finally together in theory
When was Pangaea?
Why is Pangaea not a tight fit?
things are always happening to the coast
How many m off the coast makes a better Pangaea fit
Who decided to use 200 m off the coast?
what were the evidence for Pangaea?
How were glaciers a proponent for Pangaea?
~300 mya deposits
worldwide ice age or continents move
same time period has coal deposits in North America
How were fossils a proponent for Pangaea?
mesosaurus - before would have been magiced from south america to africa
Continental Drift Hypothesis - lines of evidence
fit of continents
distribution of organisms
Mechanisms of doubt for Pangaea
continents "plow" through the ocean basins - claculations showed this to be incorrect
continents moved because of gravitational attraction between sun and moon
structure of earth
how much of the world does the crust make up?
How thick is the crust
what is the density of the crust?
What rocks make up the crust?
Al, Si, O
What percent of the earth is the mantle?
how thick is the mantle
What rocks make up the mantle?
Dense, Hot rocks
Mg, Fe, Si, O
What percent of the earth is core?
How thick is the core?
What state is the outer core?
what state is the inner core
How does pressure effect melting points?
increase pressure = higher melting point
9900 without pressure to 22000 degrees F with pressure
What is the characteristic make up of the continental crust?
thick and light
what is the characteristic makeup of the oceanic crust?
thin and dense
Characteristic rock of the continental crust?
Characteristic rock of the oceanic crust?
What is the characteristic makeup of the upper mantle
even denser rock
What is the boundary between crust and the mantle called?
Who was the Moho named after?
Where is the Moho closest the surface?
Ocean - because thinner
Boyancy and Isostatic Pressure
if weight added - displaces more water
the vertical movement of the crust
What is isostatic adjustment the result of
the buoyancy of the earth's lithosphere as it floats on the denser, plastic like asthenosphere below
how far was Canada depressed why
1640-2300 ft below present
level undercover of ice 1.2-1.9 miles thick
More evidence for continental drift
Oceanic crust younger than continental crust
midatlantic ridge conform to shoreline
What is the worlds largest mountain chain
Who discovered the mid-oceanic ridge?
Harry Hess - US Navy Captain
When did Harry Hess discover mid-ocean ridges?
How did Harry Hess discover mid-ocean ridges?
during WW II left depth recorder on all the time and noticed
What did Harry Hess notice during WWII
1. extensive mountain ridges in the center of ocean basin
2. extremely deep ocean trenches at the edge of the ocean basins
3. undersea volcanoes had flat peaks
4. less sediment at mountain ridges
where is the oldest sea floor
where is the newest sea floor
by ridges - not quite as dense
why are there flat volcanoes below the sea
by the contients
where are peaky volcanoes
What did Harry Hess call Sea Floor Spreading?
Sea floor spreading
1. New crust formed at ridges
2. Volcanoes that form are close to surface - eroded=flat top
3. Deep ocean trenches are where sea floor descends back into mantle
4. Mud and sediments deposited on the ocean floor thin toward the mid-ocean ridges
What did Drumand Mathews and Fred Vine do?
measured first magnetic anomalies in the Indian Ocean
Who first measured magnetic anomalies
Drumand mathews and Fred Vine
Who discovered earth's magnet field and when
Carl Friedrich Gaus
where as the history of plate movement been captured
residual magnetic fields
formed from cooling magna that contains iron oxide
How often does the earth's magnetic field flip?
200,000 years on average
When was the last time the earth's magnetic field flip?
750,000 years ago
What is the time between magnetic field reversals like
How does the earth prepare for a magnetic flip?
declining pretty steadily
take a really long time
what is a flat volcano called?
Where has a history of plate movemnt been captured?
in residual magnetic fields
formed from the cooling magma that contains iron oxide
strips of magnetism were a historical record of new sea floor
Two theories about crust being driven apart
1. ridge push
2. slab pull
boyant magma pushes up driving plates apart
old dense, heavy plate sinks pulling plates behind also called slab suction - conveyor belt movement
ocean floors and deep sea trenches
divide into 3 parts
the continental shelf
the relatively shallow (up to 200 meters) seabed surrounding a continent
lies at water depth
broad underwater plain
Deep Ocean Basin
A flat-topped submarine mountain
A broad, relatively flat region of the ocean that lies at least 4.5 km below sea level
Relatively small topographic features of a dominantly flat, deep-ocean floor, commonly 50-250 m in height and a few kilometers in width. They are most typical of the Pacific Ocean floor at depths of 3000-6000 m
What is the deepest point in the earth's ocean?
Challenger Deep in the Marina Trench
How deep is the Challenger Deep?
Who went down in the challenger deep?
Don Walsh and Jacques Piccard
How deep did Don Walsh and Jacques Piccard go?
How long was their time underwater and how long were they on the bottom?
What are three big geologic plates
Where do most earthquakes happen?
Along plate lines
How fast do plates move on average?
What movements are caused by plate techtonics?
Divergent Plate Boundaries
boundries between plates moving apart
example of divergent plate boundary
What is the techtonic process of a divergent plat boundary
sea floor spreading, new sea floor created
What crust interacts in a divergent plate boundary
oceanic to oceanic crust
What does a faster spreading divergent plate boundry look like
broader, less rugged
What are earthquakes relationship to divergent plate boundaries
amount of energy released is related to spreading rate
Faster spread - less energy relased in each earthquake
where does the mid-atlantic ridge come onland
What is a divergent plate boundrary on land called?
convergent plate boundary
regions where plates are pushing together
buckling and shortening
What are the three types of convergent plate boundaries
What is an example of oceanic-continetal convergent plate boundary and what happens?
old sea floor destroyed
What is an example of oceanic-oceanic convergent plate boundary and what happens
Aleutian Islands - Island arc formation and trenchs
old sea floor destroyed
What is an an example and what happens at continental-continental convergent plate boundary
sea floor not created or destoryed
transform plate boundries
What is an example of a transform plate boundary and what does it do?
San andreas Fault
sea floor not created or destoryed
What are the three types of transform plate boundaries
Example of a place that there is no plate movement, but geologic activity
don't know why
certain areas in mantle get hot areas - can come all the way to surface
1. continent rift
2. sea floor created
5. sea smaller
the sun is the primary force of energy on earth
What drives the circulation of the atmosphere and the ocean and is the source of energy for almost all living organisms?
elements in atmosphere
How much N is in the atmosphere
How much o is in the atmosphere?
How much Ar is in the atmpshere
How much carbon dioxide is in the atmosphere an dhow much is is it increasing and how much in Aug 2010
Who came up with the greenhouse effect and when\
What is the difference of sunlight if the earth was flat vs. round
flat- sun come in fairly easilya nd evenly
round- different areas getting less sunlight, start to bend
what is the tilt of the earth
the fraction of incident electromagnetic radiation reflected by a surface
forest and ocean
ice caps and clouds
How does albedo help melt the ice caps
pools of water absorb
then melt more and absorb more
melt and absorb
is heat transported
atmoshpereic and oceanic circulation
warm air rises
cold air falls
Air holding water vapor
cool air cannot hold much water vapor so typically dry
warm air can hold more water vapor so typically moist
How does water vapor effect density
water vapor decreases the density of air
Pressure, air, and water vapor
a column of cool, dense air caused high pressure at the surface - sinking air
a column of warm less dense air causes low pressure at the surface - rising air
Where is there the most intense radiation
at the equator - warm air
What are the three convection cells and what are their latitudes?
Hadley Cell 0-30
Ferrel Cell 30-60
Polar Cell 60-90
What to these convection cells on the earth create?
What is another name for the equator?
what is a name for 30 degress latitude
What winds are between the doldrums and the horse latitudes
NE and SE trade winds
What winds are between 30-60 degrees latitude
What winds are between the 60 and 90 latitude
What is global climate driven by *
1. differential heating of the tropics - amount of radiation over larger surface area at poles, radiation travels through more atmopshere at poles