Plate tectonics overview powerpoint

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Where are the Earth’s tectonic
plates and their boundaries?
What happens at plate boundaries?
How do Earth scientists classify
plate boundaries?


Part 1.
Identify the patterns of your area of expertise
– volcanology, seismology, geography,
geochronology - AT PLATE BOUNDARIES
 Describe what you observe – do not interpret
what you see, just describe the patterns
 Wide or narrow, straight or curved, symmetric
or not symmetric, deep or shallow, ridge or
valley, active or inactive
 Identify 3-5 boundary types; color each on
your transparency; define in words



Part 2.


Bring together areas of expertise –
volcanology, seismology, geography,
geochronology



Correlate your data sets; what collective
patterns emerge?



Identify 3-5 boundary types; color each on a
master transparency; define in words


Part 3.
 Describe the different types of boundaries
 What patterns were related in the different

data sets?


Plate Boundaries
Where Stuff Happens


Plate Tectonics

• The upper mechanical layer of Earth (lithosphere) is
divided into rigid plates that move away, toward, and along
each other
• Most (!) geologic action occurs at plate boundaries in
DISTINCT patterns


Compositional

Physical / Mechanical







1. Divergent Boundaries
•Volcanic activity in fissures, some volcanos
•Shallow earthquakes, on plate boundary
•Young crust, symmetrical around boundary
•Ridge
•Rocks?
MidAtlantic
Ridge

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r
e
m
A
th
Nor Plate

Eur
as i a

n
Pl a
te



Nazca Plate

South American Plate
Antarctic Plate



Andes Mountains



2. Convergent Boundaries
(a) Ocean-continent convergence
•Volcanos tight, parallel boundary, landward
•Shallow to deep earthquakes
•Age varies on one side of the boundary; not symmetrical
•Trench, mountain chain
•Rocks?

Andes
Mountains

Peru-Chile Trench

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a
l
P
a
c
Naz

South
American
Plate






2. Convergent Boundaries
(b) Ocean-ocean convergence
•Volcanos tightly spaced, parallel boundary, arc
•Shallow to deep earthquakes
•Age varies on one side of the boundary; not symmetrical
•Trench, volcanic island chain
•Rocks?

Mariana Islands
Marianas Trench

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n

i
p
ip
Phil
e
Plat

Pacif
i c P la
te