Inside The Earth Flashcards
Structural layers
Layers of the earth based on their physical properties temperature density and flow dense=tightly packed heavy
Lithosphere asthenosphere mesosphere outer core and inner core 5physical layers
Compositional layers
Earths layers defined by what they are made of. Crust mantle and core 3 compositional layers
Crust
The outermost thinnest layer of earth made of continental crust and oceanic crust.
Continental crust
Thicker but less dense than oceanic crust. This layer rises above the oceanic crust.
Oceanic crust
Thinner but more dense than continental crust this layer will sink below the continental crust
Mantle
Layer between the crust and the core very thick layer contains most of earths mass made of iron and magnesium
Core
Layer from the bottom of the mantle to the center of the earth. Made mostly of iron.
Lithosphere
The outermost rigid layer rigid=stiff unable to bend made of the rust and upper part of the mantle divided into pieces called tectonic plates
Asthenosphere
The soft layer of the mantle. Made of rock that moves slowly.
Mesosphere
The strong lower part of the mantle goes from bottom of asthenosphere to core
Outer core
The liquid that surrounds the inner core. From the bottom of the mantle to the inner core. Made of nickel and iron.
Inner core
The solid dense center of the earth. Innermost layer made of iron and nickel.
Tectonic plates
Pieces of the lithosphere that move on top of the asthenosphere
Plate tectonics
The idea that pieces of earths lithosphere move on top of the asthenosphere. Used to explain continental drift and sea floor spreading. Three forces move the plates. Ridge push convection slab pull
Ridge push
When oceanic plates slide down where the lithosphere and asthenosphere meet oceanic lithosphere is higher before it sinks below the continental lithosphere so it slides
Convection
When hot earths hot material, magma, rises, then sinks when it cools the plates are dragged sideways
Slab pull
When the edge of the oceanic plate sinks and pulls the rest of the tectonic plate with it happens because the oceanic lithosphere is more dense than the asthenosphere.
Plate boundary
The place where tectonic plates meet or separate. Three types. Divergent convergent transform.
Convergent boundary.
When two plates push against each other what happens is decide by the types of crust that meet. 3 types. Continental/continental. Continental/oceanic oceanic/oceanic
Divergent boundary
When two plates move away from each other. Mid ocean ridges are the most common
Transform boundary
When two plates slide past one another. Makes earthquakes.
Subduction zone
An area where one tectonic plate sinks below another. Oceanic is denser so it sinks below continental
Alfred Wegener.
The scientist that said the continents drifted away from each other. How he explained it
Continents fit together
Plants and animal fossils from different climates found on both sides of Atlantic Ocean
Similar types of rock found in different places
Cuts in stone from glaciers matched on different continents
Continental drift
The theory that the continents drifted apart. Theory made by Alfred Wegener. He couldn’t prove how the continents moved
Pangaea
The one large landmass before the continents parted.
Sea floor spreading
The creation of new oceanic lithosphere when plates move apart and spread the sea floor. The oldest crust is found near the continents. Mid ocean ridges (under water mountains) are where sea floor spreading happens.
Magnetic reversal
When earths magnetic poles change places. Proof of sea floor spreading.
