Earth Science WIP Flashcards
(34 cards)
Continental Drift Theory
continents were once joined as one supercontinent and slowly drifted apart
Alfred Wegener
proposed the continental drift theory
Seafloor Spreading Theory
a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge
Plate Tectonic Theory
the Earth’s crust is divided into different plates; occurrences of volcanoes and mountains are widespread in the boundaries of each plate
Plate Boundaries
caused by convection currents in the mantle
Convergent Boundaries
2 plates slide towards each other
Mountain Ranges and high plateaus
Continental-continental convergent
(the older plate subducts under the younger plate)
Trenches, Island and Volcanic Arcs
Oceanic-oceanic convergent (the older plate subducts under the younger plate)
Trenches and Volcanic Arcs
Continental-oceanic convergent (the denser oceanic plate subducts under the less dense continental plate)
Divergent Boundaries
plates slide apart from each other
Rift Valley
Continental-continental divergent
Mid-ocean ridge
Oceanic-oceanic divergent
Transform Boundaries
plates slide pass each other
Earthquakes
Transform
Crust
outermost layer of the Earth
Mantle
middle layer of the Earth; composed of molten rock called magma
Outer core
layer of molten substance
Inner core
layer of solid substance (due to pressure)
Thinnest layer
Crust
SiAl (Silicon and Aluminum)
Continental Crust
1/3 of Earth’s surface
Continental Crust
Mostly granite
Continental Crust
2/3 of Earth’s surface
Oceanic Crust
Mostly Basalt
Oceanic Crust