The thinnest layer of the Earth
What is the crust
There are ______________ main physical layers of the Earth.
What is three?
Created the Continental Drift Theory
Who is Alfred Wegener?
Earthquakes and Volcanoes are usually located in relation to these
What is a plate boundary?
The Himalayan mountains are the result of a ___________________________ boundary.
What is convergent boundary
A number of rigid, but moving, pieces of Earth's surface
What is tectonic plates?
The thickest layer of the Earth
What is the mantle?
Evidence of matching animal fossils from two separate continents _____________________ and _____________________
What is Africa and South America
The mid-ocean ridge is an example of a ____________________ boundary. and
What is divergent boundary?
Hot air or liquid will _______ above cooler denser air ot liquid.
What is rise?
The theory that all continents are fragments of Pangaea now drifting apart
What is the Continental Drift Theory?
Plates float on top of the _______________________.
What is the asthenosphere?
Evidence of the same _______________were found on Africa and South America
What are fossils?
___________________ occurs here where new ocean floor is formed at a divergent boundary.
What is sea floor spreading?
_________________ are a result from the build up of stress at a transform boundary.
What are earthquakes?
States that youngest rocks of ocean floor are at divergent boundaries, moving outward
What is seafloor spreading?
The rigid part of the Earth including the crust and the upper mantle (makes up the plates of the Earth)
What is the lithosphere?
Pangaea existed this many millions of years ago
What is around 250 million years ago?
This is the mechanism (what causes) the plates to move
What is convection cycles in the mantle?
The San Andreas Fault in California is an example of a ____________________ boundary.
What is a transform boundary
Although the hottest layer of the Earth, this layer is solid metal
What is the inner core?
The Earth's crust is thinnest under the _____________________ and thickest under the _____________________.
What is thinnest under the ocean and thickest under the continents?
Continental Drift Theory was not accepted because it did not explain this
What is how the continents moved?
This can happen at convergent boundaries
What is subduction (where volcanoes often occur) and collision (where mountains are usually formed)?
Pyroclastic materials build this type of volcano.
What is composite?