1. What is a plate boundary?2. Copy today’s date and EQ on
page 87 if you did not yesterday.
The place where two plates move apart or diverge is called a divergent boundary.
This is a model of sea floor spreading at a divergent boundary called a mid ocean ridge.
Did you know that the Earth’s longest mountain range is underwater and is called the mid-ocean ridge?
: www.ocean.udel.edu
The Mid-Ocean Ridge system, shown above snaking its way between the continents, is more than 56,000 kilometers (35,000 mi) long. It circles the earth like the stitching on a baseball!
A convergent boundary is where two plates come together, or converge. The result of the plates hitting together is called a collision.
A transform boundary is a place where two plates slip past each other, moving in opposite directions.
Continental crust to continental
Continental crust to oceanic
Oceanic crust to oceanic
from: http://www.geo.lsa.umich.edu/~crlb/COURSES/270
Continental crust to continental crust collision
India-Asia (Himalayas)
Before collision
After collision
Also the way the Appalachian Mountains formed!
Because one plate gets pushed under another, it is called subduction. This is where volcanoes form!
Oceanic crust colliding with oceanic crust
Oceanic crust colliding with continental crust
all from: http://www.geo.lsa.umich.edu/~crlb/COURSES/270
The process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle is called
Plate tectonics video clip
Here is an great link for seeing where each type of boundary is located.Click here for a great hyperlink! Make sure you click on each type of boundary in the key!
Worldwide Earthquake patterns help us know where the edges of plates are located
The Earth’s Plates
Here you see the two slides together. What do you see?
http://www.livescience.com/images/pangea_animation_03.gif