Earth's Interior Layers
Describe Earth's INNER core.
dense ball of SOLID metals (iron and nickel)
The lithosphere is broken up into ___, which "float" on top of the asthenosphere.
plates
What is Pangea?
supercontinent that existed hundreds of millions of years ago
When scientists observed the mid-ocean ridge, they noticed ___, formed by rapid cooling of molten material.
pillow shaped rocks
The process in which the ocean floor sinks beneath a deep ocean trench, back into the mantle is ___.
subduction
The Theory of ___ states that pieces of Earth's lithosphere are in constant slow motion.
Plate Tectonics
What is the correct order or Earth's layers beginning with the outermost layer.
crust, upper mantle, lower mantle, outer core, inner core
Scientists believe convection currents flow in Earth's ___.
upper mantle or asthenosphere
Rocks on the seafloor that lie in a pattern show a record of the reversal of Earth's ___.
magnetic field
How did scientists discover that rocks farther from mid-ocean ridges were older?
drilling samples and testing the age
The place where two plates slip past each other in opposite directions is a ___.
transform boundary
Subduction occurs where the oceanic crust bends down toward the mantle at a ___.
deep ocean trench
Holes drilled into Earth's crust provide DIRECT evidence of the interior of Earth in the form of ___.
rock samples
Heat transfer within a FLUID takes place by ___.
convection
Drilling samples revealed that rock samples taken from farther away from a mid-ocean ridge are (older/younger) than those closer to the ridge.
older
This landform is the result of seafloor spreading, when molten material rises from the mantle and erupts.
mid-ocean ridge
A rift valley forms at this type of boundary.
divergent boundary
Using data from seismic waves, geologists have learned Earth is made up of several ___.
layers
Geologists obtain INDIRECT evidence about Earth's interior by ___.
studying seismic waves
In the mantle, heat is tranferred as soft rock flows slowly in cycles is known as ___.
convection currents
Wegener hypothesized that the continents were once joined together. His theory is called ___.
Theory of Continental Drift
Geologists believe the force that moves Earth's plates is caused by ___.
convection currents in the asthenosphere/ upper mantle
A collision between two pieces of continental crust at a convergent boundary produces which landform?
mountain range
The part of the mantle that bends like plastic (play-doh) is called ___.
asthenosphere
Earth's magnetic field is the result of the movement of ___.
the outer core around the inner core
Describe a convection current in the upper mantle.
-occurs in asthenosphere
-less dense, heated rock rises toward lithosphere
-spreads out under lithosphere
-cools off and becomes more dense
-sinks back into asthenosphere
-cycle starts over, reheats... rises...
Explain Wegener's four pieces of evidence supporting Continental Drift.
-apparent fit (explain)
-fossil correlation (explain)
-mountain correlation (explain)
-paleoclimate data (explain)
The process of ___ continually adds new crust to the ocean floor along both sides of the mid-ocean ridge.
seafloor spreading
When continental plates pull apart at a divergent boundary on LAND, this forms.
rift valley
A place where two plates come together is known as a ___.
convergent boundary