Plate Tectonics: A Scientific Revevolution Flashcards
What did most geologists Believed since the 1960s?
They believe the ocean basins and continents had a fixed geographic positions.
What is the Continent Jigsaw Puzzle?
The Continent Jigsaw Puzzle is a fit of the continent coastlines provided suggestion the continents were once connected.
What are the supporting Hypothesis that wegener come up with?
Shape of Continents-
Fossil Match across the seas-
Rock types and structures match-
Ancient climate-
What is the difference between the whole-mantle convection model and the layer cake model?
The Mantle of the layer cake is the division at the depth and there are two zones of convection and the whole- mantle is a descending oceanic crusts descends to great depth.
What do Geologist think of the plate motion?
They agree that subduction of cold, dense slabs of oceanic lithosphere is a minor driving force motion.
What is the Mantle plumes?
a form of upwelling hot rock from the deep of the mantle
What were the two objection to wagerer’s Hypothesis?
Lack of Mechanism: gravitational forces of the moon and sun produce Earth’s tides were capably of gradually move continents: it doesn’t because earth rotation.
Continental Breakthrough: suggested that continents broke through thinner oceanic crust. There were no evidence
What is oceanic crust composed off?
What is continental crust?
Oceanic crust: composed of basalt, denser rock rich in iron and magnesium.
Continental crust:consists of less dense granitic rock.
What is Asthenosphere?
(The word asthenos mean weak)
Hotter, weaker layer of mantle below the lithospheres.
What is lithosphere?
Lithosphere is composed of plates is constant motion, with major interaction occurring at their boundaries.
What are the seven Major of lithosphere?
North American, South American, Pacific Eurasian, African, Australian-Indian and Antarctic.
How are plate boundaries established?
based on the location of the earthquake and volcanoes.
How are lithospheric plate are moved and what is the cause?
Lithospheric plate moves rigid units to each other.
The cause is the distance between locations on different plates changes.
What is divergent, convergent and transform plates boundaries?
Divergent is plate moving apart,
Convergent is plate moving together and transform fault are plates sliding horizontal past each other.
What is the formation of the new oceanic lithosphere?
Tow close plates moves apart, leaving long narrow fractures in the ocean crusts.
