Plate Tectonics Flashcards
German Scientist that studied plate tectonics and the continental drift theory
Alfred Wegener
Supercontinent of all the continents
Pangea
Theory that continents are in constant motion on Earth’ surface
Continental Drift
four evidences of Continental Drift
Similar rocks on different continents
Coastlines lined up like a puzzle
Same fossils found on different continents
glacial grooves
Name six facts about Alfred Wegener
Died in 1930 Born in Berlin 1880 Fifth of five children Father was a minister Parents ran orphanage up to 15 orphans Loved to read Meteorologist Astronomer Geo-physicist Studied climates Four polar expeditions First man in world to use kites and balloons to study weather In 1906 his brother kurt and him set a world record for balloon flight of 52 and 1/2 hour Two days and four and a half hours Went on first expedition to greenland in 1908 No one believed his theories at first
The longest chain of mountains on Earth.
Mid-Ocean Ridge
Worlds longest ridge, running the length of the Atlantic Ocean, because the north and south american plates are divergent moves from Eurasian and African plates.
Mid-Atlantic Ridge
A deep valley formed under water as tectonic plates move apart. Red Sea was formed this way.
Rift Valleys
Heated rocks rise in columns from the mantle. Volcanoes usually develop above the plumes at the surface of a tectonic plate. Volcanoes may rise high enough above the sea to form islands. Hawaii islands formed this way.
Hot Spots
When the North Pole magnetic field changes with the South Poles magnetic field. 4-5 reversals every million years.
Magnetic Reversal
When a plate descends into earth along a convergent plate boundary.
Subduction
Layers of the Earth
Inner Core Outer Core Mantle Asthenosphere Lithosphere
Large slabs of rock that fit together like a puzzle. Make up the surface of the earth.
Tectonic Plates
The hot soft rock rises, cools, at the top of the cycle and sinks, then is heated again and rises, a motion that transfers heat in a material. Very slow process.
Convection Current
Wegener observed the similarities of coastlines between continents that were separated by _____.
oceans
Fossils of plants and animals that lived in wet, warm climates are in areas that now have _________ climates.
cold
Wegener suggested that these continents were covered by a large sheets of ________.
ice
Wegener proposed that certain continents-including South america and Australia-were closer to the _________ pole 250 million years ago.
south pole
What is on continents that currently have warm climates show that these continents once had cold climates.
glacial grooves
Evidence of continental drift also includes __________ on different continents that have similar or identical chemistry, geologic structure, and age.
mountains (i think)
Additional evidence to prove Wegener’s hypothesis existed on the _______ between the drifting continents.
seafloor
Coal beds in Antarctica suggest that the continent once had a warm climate. TRUE or FALSE
true
molten rock cools and becomes _________
basalt
Magnetic stripes on either side of the ridge is parallel on the same sides TRUE OR FALSE
true
______________ are mountain ranges in the oceans, where the crust is young and there is almost no sediment.
mid ocean ridges
Ocean-Ocean
the collision of the tectonic plates and the seafloor spreads
Ocean-Continent
line of volcanoes and it forms volcanoes
Continent-Continent
when two plates collide and it forms mountains
what type of plate occurs between the north American Plate and the Eurasian Plate
divergent
What does coal beds have to do with Antarctica. What’s their significance
Coal is remains from dead animals. There is no way the fossils found in Antarctica could have lived in such cold weather. This shows us that not only have the continents moved but the Earth weather has also changed.
What did early mapmakers find
They found that fossils of exactly the same plants and animals were located on continents that are separated by thousands of miles of oceans
Sediment forms on top of the oldest oceanic crust creating a smooth seafloor named what?
abyssal
When new oceanic crust forms along the mid-ocean ridge OLDER crust moves away from the ridge TRUE OR FALSE
true
Norman Polarity is when a magnet points North and Reverse Polarity is when it points South TRUE OR FALSE
this is known as what
true, magnetic reversal
What is subduction
when plates collide and the plates that are denser slides under less-dense plate
Convergent Plate Boundary
push together
Divergent Plate Boundary
move apart
Transform Plate Boundary
rub/scrape
What material is something that is capable of changing its shape without breaking
plastic
mountain ranges and rocks share common origins TRUE OR FALSE
true
