Earth Science - Earth Layers, Magnetism & Plate Tectonics

lithosphere composition

crust & upper mantle, rock (hard like jolly rancher)

Crust, Lithosphere, Upper Mantle, Middle Mantle/Asthenosphere, Lower Mantle Inner Core all have this same state of matter

solid

Earth as a magnet

the Earth acts like a magnet because of the liquid outer core made of iron and nickel which spins as the earth rotates and creates a magnetic field and the north & south poles on earth

Where can a compass be used for navigation & why?

On land & at sea because the magnetic field is so large it can be used by a compass anwhere

Describe what happens at the two plate boundary locations between the Pacific Plate & the North american Plates?

*Where the arrows move in opposite directions past one another, this is a transform boundary and earthquakes may occur here. *Where the arrows move towards one another, the plates are converging (i.e. colliding) & one must subduct (the pacific) beneath the other (the North American). A mountain range occurs here.

Lower Mantle Location on Earth

Below the asthenosphere

Compare what happens between the cocos & Caribbean Plates to what is happens between the Antarctic & South American Plates.

Both plate relationships are convergent. One plate in each will subduct beneath the other causing volcanic activity or mountain formation.

At what type of plate boundary do volcanoes occur?

Convergent & Divergent

At what type of plate boundary do mountains form?

Convergent, (underwater - divergent)

Inner Core Location on Earth

Inner core is located under the mantle

Outer Core State of Matter

Liquid

The tectonic plates are part of this Earth layer

Lithosphere

Outer Core& Inner Core Composition

Metal (Iron & nickel)

Composition of Rock, Upper Mantle & Lower Mantle

Rock

Middle Mantle/Asthenosphere Composition

Rock (soft like laffy taffy)

What is it called when an oceanic plate dives beneath a continental plate?

Subduction

Why is a compass composed of a frictionless bearing & a lightweight magnet?

To allow the needle to turn easier because Earth's magnetic field is very large

Middle Mantle/Asthenosphere Location on Earth

Under the lithosphere, the lithosphere floats on this (where the convection currents are)

Outer Core Location on Earth

Under the mantle

What is the cause of an earthquake?

When plates slide past one another at a transform boundary and energy stored in the Earth's crust is suddenly released.

Describe what happens between the American Plate and the Eurasian plates?

Where the arrows move away from one another, the plates are diverging (separating) & new crust is created here (and possibly volcanoes).

inner core

a dense sphere of solid iron and nickel at the center of the Earth

On average the Earth's lithospheric plates move about how far each year?

a few centimeters

outer core

a layer of molten iron and nickel that surrounds the inner core of the earth

magnet

a material that attracts steel, iron, cobalt, and nickel

divergent boundary

a plate boundary where two plates move away from each other

transform boundary

a plate boundary where two plates move past each other in opposite directions

convergent boundary

a plate boundary where two plates move toward each other

lithosphere

a rigid layer made up of the uppermost part of the matle and crust

compass

an instrument composed of a small, light-weight magnet called a needle, that is balanced on a frictionless bearing

Ways in which the Earth is like a magnet

both have poles (north & south) both are composed of (nickel & iron) both create a magnetic field both attract iron & nickel

volcano

forms where plates diverge and magma reaches earths surface & where plates collide and one subducts into the mantle forming molten material

lithosphere location on Earth

part crust, what the tectonic plates are made of

upper mantle location on Earth

part of the lithosphere

continental drift

the hypothesis that the continents slowly move across the Earth's surface

mantle

the layer of hot, solid material between Earth's crust & core

crust

the layer of rock that forms Earth's outer surface

sea-floor speading

the process by which molten material adds new crust to the ocean floor

subduction

the process by which ocean floor sinks beneath a deep-ocean trench and back into the mantle

What creates Earth's magnetic field?

the rotational forces within the Earth's liquid from iron layer (the outer core)

asthenosphere (convecting mantle)

the soft layer of the mantle on which the lithosphere floats

plate tectonics

the theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle

crust location on Earth

top layer also part of the lithosphere

earthquake

when plate boundaries slide past each other, build up pressure & cause a sudden, violent shift

mountain building

when two plates collide & crush together causing land to be pushed up, resulting in the folding and breaking of Earth's crust