Download Plate Tectonics Part 1-maybe Jan 29

Plate Tectonics-Lesson Three
In outward appearance, the earth is a nearly spherical ball with a radius of 6350 kilometres.
Internally, the earth consists of three major layers. They are:
crust
 a thin layer of rock and it forms the earth's surface
 a thin silicate rock material
 75% of the earth's crust is covered with water.
 The thickness of the crust ranges from about 8 kilometers under the oceans to about
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40 kilometers under the continents.
Animals and plants live on the crust.
Mantle
The mantle is a thick layer of rock below the crust. It is located between the crust and the
core. It is dense and mostly solid silicate rock.
Core
The core consists of two parts: the inner core and outer core.
 the inner core: a solid metal core made up of nickel and iron (1200 km diameter)
 the outer core: a liquid molten core of nickel and iron
 The temperature in the core is hotter than the Sun's surface.
 This intense heat from the inner core causes material in the outer core and mantle to
move around.
Plates
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The crust and upper mantle is made up of plates.
The crust and upper mantle is called the lithosphere
Scientists believe that the plates move about 2 inches per year.
The lithosphere is broken into giant plates that fit around the globe like puzzle pieces.
they slide on top of a somewhat fluid part of the mantle.
the fluid part of the mantle is called the asthenosphere.
There are many plates. However, for CARS2301 we are going to focus on the
 Caribbean plate
These plates have edges which are called either
 plate margins
 plate boundaries
o sometimes they cause:
 earthquakes
 volcanoes
 they build mountains
 These plates meet each other at three kinds of margins
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o Divergent( Constructive)
 Move apart
o Transform (Fault)
 Slide past each other in opposite directions
o Convergent (Destructive)
 Move toward each other and collide
 One is forced back into the mantle (subduction)
They are located in the Caribbean
o Divergent margin
 Maybe developing west of Jamaica(Sealy 1992)
o Convergent margin
 West and east of the Caribbean Plate
o Transform margin
 North and south of the Caribbean Plate
Draw the boundaries of the Caribbean Plate
 under Cuba and Bahamas and Cayman
 edge at top of Hispaniola
 the border of Belize
 follow the line
o Over El Salvador and Honduras
 Bottom line of Trinidad including northern part of Colombia Venezuela
 Leave out Guyana
 Come edge of Panama
o And cut off a little bit at the bottom (Tonosí in Panama)
 Go left to connect this line over El Salvador and Honduras through Guatemala