What is Oceanic crust called
Oceanic plates consist of an oceanic crust called "sima"
The four layers that make-up the earth’s composition are?
Crust, Mantle, Outer Core and Inner Core
What causes Volcanoes?
Volcanoes happen when magma rises to the surface of the earth
The process that continually adds new crust is
Sea-floor spreading
Who is the person that discovered the supercontinent?
Alfred Wegener
what is continental crust called
Continental plates consist of a continental crust called "sial"
The plastic, semisolid layer that contains a convection current that moves the plates is called a?
Inner Core 
What Plate Tectonics cause Volcanoes
Divergent Plate tectonics and Convergant plate tectonics such as subduction zones , rifts and mid-oceanic ridges
The depth of the mantle is?
The second layer, Mantle, lies beneath the crust and this zone starting from the lower boundary of the crust continues up to a depth of 2,900 km
if a continentaly plate and an oceanic plate decided to slam into each other (subduction), which one would sink into the mantle? (Hint: think about which one is denser!!!)
Oceanic Plate
What is the continental crust made of?
Continental crust is made up of silicon and Aluminum
Large pieces of lithosphere that move around on the Asthenosphere are called
Tectonic plates
what plate boundaries cause earthquakes?
Divergent Boundaries move away from each other and cause earthquakes
The thickness of the 2 layers of the upper mantle is approximately said to be?
The upper mantle is further divided into two layers of 400 and 600 km thickness respectively
How do scientists learn about the interior (center) of the earth?
Seismic Waves
what are Oceanic plates made of?
Oceanic plates are made of silicon and magnesium
The hypothesis that land masses spread apart from each other and have done so in the past is known as?
Continental drift
what plate Boundaries cause Tsunami's?
Subduction Zones often cause Tsunamis
The exact nature of the mantle is completely understood. State true or false
FALSEHOOD It is said that the exact nature of the mantle is as yet incompletely understood
Pangaea existed about
335 million years ago
what happens when convergent boundaries push together
a plate will move under the other this is called subduction they may also cause earthquakes
Where does sea-floor spreading take place?
Mid-Oceanic Ridges
which plate boundaries cause Mountains
convergent Boundaries
Who was the first person to tell about the Core?
The existence of the core was suggested by R.D. Oldham in 1906 and subsequently confirmed by other seismologists
Earth's crust is broken into pieces called?
They are called Plates ....obviously