plate tectonics Flashcards
what is pangaea
Pangaea broke up to form the current continents
what is the evidence for continental drift
- continental fit
- similarity of rock sequences and mountain ranges
- glacial evidence
- fossil evidence
what theory was the continental drift replaced by
the theory of plate tectonics
what does the theory of Plate tectonics say
seafloor separates at oceanic ridges
new crust is formed by magma
as the magma cools the new crust moves away from the ridge
how has seafloor spreading been confirmed
deep sea drilling
new oceanic crust forms along the ridges
how does the theory of plate tectonics help us understand the earth
it helps us understand forces life volcanoes, earthquakes, and mountain building
what does the core consist of
- small solid inner region
- larger liquid outer layer
what is the core composed of
iron and small amount of nickel
what are the 3 parts of the mantle
- solid lower mantle
- partially molten atmosphere
- solid upper mantle
what is the mantle composed of
peridotite
what is the crust
thin outer skin of earth
consists of thin oceanic and thick continental crusts
what is the crust composed of
the lithosphere
what is the driving mechanism of plate tectonics
Mantle cell convention
what is mantle cell convection
“pot of step scenario”
heat at the bottom moves carrot up, as the carrot cools it falls back down and all over again
