Evidence of Plate Tectonics Flashcards
Who proposed the continental drift theory?
Alfred Wegener
What are his evidences to support his theory - Continental drift theory?
Continents fit like jigsaw puzzle, fossils of the same kind are found on different continent, rock types and paleoclimate data.
TRUE OR FALSE
Mesosaurus, cynognathus, lystrosaurus and glossopteris are the fossils found on different continents.
TRUE
TRUE OR FALSE
Before we have the 7 continents, it is once became a one big landmass called Pangaea, which means “all the earth” in Greek.
TRUE
IDENTIFY
The ocean surrounding Pangaea is called ___________ which means “__________” in Greek.
Panthalassa, “all seas”
Where they found the same remains of a mesosaurus that had split up when continents parted?
South America and South Africa
TRUE OR FALSE
They discover different fossils on different countries.
FALSE, same fossils
Explain the 3rd evidence of Alfred Wegener: Rock and Mountain Correlation/ Geological structures and rock types.
It was discovered that mountains found on different continent have the same rock types. They were formed at the same time and place together but had split up when continents moved.
tropical plant remains
bituminous coal
Explain what happened to glaciers/glacial striations and sedimentary rocks on the 4th evidence of Alfred Wegener.
Glaciers/glacial striations are found on hot or tropical regions. Sedimentary rocks were found on cold regions.
TRUE OR FALSE
Wegener died when he could not give evidence /support for his evidence.
TRUE
Tectonics plate are similar to?
Lithosphere plates
What is the giant magnet?
Earth
What is the reason why the scientific community rejected Alfred Wegener’s theory even though he gave several evidence?
Because they are looking for another evidence that was lacking on Wegener’s theory. That is the mechanism of continental drift or what driving forces made the continents moved.
What is the lacking evidence of Alfred Wegener?
Mechanism of continental drift or what driving forces made the continents moved.
Area of magma that punch through a single plate.
hotspot
TRUE OR FALSE
The lithosphere is broken into plates.
TRUE
Because of the hotspot and continuous movement of plates, what is formed?
chain of hotspot volcanic islands
What drive plate motion?
Convection currents in the asthenosphere
trench : _______
convergent boundaries
ocean ridge : _______
divergent boundaries
Key figure in changing ideas about the Earth’s surface.
Alfred Wegener
Wegener suggested that Pangaea began to breakup about ______________ and the pieces drifted apart to form the present day continents.
200 million years ago
What would prove continental drift is true?
1960’s evidence
Who proposed the hypothesis of sea-floor spreading?
Harry Hess
What mission of Harry Hess he needs to study?
the deepest parts of the ocean floor
IDENTIFY
Ocean floor moves like a ____________ carrying continents with it.
conveyor belt
IDENTIFY
_____________ is continually added by the process of sea-floor spreading.
New ocean floor
Where new ocean floor forms in sea-floor spreading?
along the cracks in the ocean crust
Where older rocks are pushed in sea-floor spreading?
sides of the crack
What are the evidences for seafloor spreading?
Molten materials, drilling samples and the magnetic reversal
What showed that molten material has erupted again and again from cracks along the mid-ocean ridge and cooled quickly?
rock pillows
What showed that older rocks are found farther from the ridge and the youngest rocks are in the center of the ridge?
core samples from the ocean
Where older rocks are found in seafloor spreading?
far from the ridge
Where youngest rocks are found in seafloor spreading?
center of the ridge
It would support the continental drift theory.
Mid-ocean ridge
Why mid-ocean ridge can support the continental drift theory?
Because during seafloor spreading, sea floor/bed is moving and expanding.
What is the reason why there are gaps during seafloor spreading?
Because of the plate movements.
Another name for magnetic reversal?
Magnetic flip
It happens when the North Pole is transformed into the South Pole and the South Pole becomes the North Pole.
Magnetic reversal
Why magnetic reversal is happening?
Because of the changing directions of the flow of materials in the Earth’s liquid outer core.
What is the name when continents are join once again?
Pangaea Ultima <3
Describes one of the earliest way geologist thought continents move over time.
Continental drift
IDENTIFY
The plates are always moving and interacting in a process called _________________.
plate tectonics
What is the difference between tectonic plates and plate tectonics?
Tectonic plates are themassiveslabs of rock. While plate tectonics is the process of plates’ movement and interaction.
IDENTIFY
Some of the mostdynamicsites of tectonic
activity are _________________ and _______________.
Seafloor spreading zones and giant rift valleys
IDENTIFY
Most continental and oceanic floor features are the result of geological activity and
earthquakes along ___________________.
plate boundaries
