Plate Boundary quiz
Aluetians are... Andes are... Himalayas are...
The aleutians are ocean/ocean crust convergence and the andes are ocean/continent convergence and the himalayas are continent/continent convergence
What type of boundary is between Pacific and Indian-Australian Plates
convergent and transform
A convergent boundary is considered...
destructive because oceanic crust is destroyed
What type of plate boundary is the Great Rift Valley in Africa?
divergent
Mountain ranges under the ocean water usually form due to ...
divergent boundary
What type of plate boundaries have both volcanoes and earthquakes?
Only divergent and convergent
What forms from continent to continent boundaries?
-highest mountains -Intense metamorphism
The Andes Mountains are..
A volcanic arc
What's the difference between an active and a passive margin?
Active - tectonic activity on a plate boundary Passive- not active
What is an example of ocean to continent boundaries?
Aleutian islands
What is the boundary on west coast of south america?
Andes Convergent (steep slope)
What are the ocean to continent mountains?
Andes Mts, Rockies
Are Rockies or Andes more likely to have active volcanoes, why?
Andes because lie on the boundary (Rockies aren't as active)
What mountain range runs along the west coast of South America? What is this type of mountain range called?
Andes mts. (volcanic arc)
What are all the convergent mountain ranges?
Andes, Alps, Atlas, Rocky, Himalayas, Pyrenees and Appalacian
Where do rift eruptions occur?
At long, narrow fractures in crust
Why are the himalayan mountains so big?
Because continent to continent convergence
What type of plate boundaries are at oceanic mountain ranges?
Bottom of the ocean floor- divergent
Faults
Breaks in Earth's crust where rocks have slipped past each other
How do you know a mountain range is divergent or convergent?
Divergent is in the ocean and convergent is on continent
WHY does earthquake depth change as you move from west to east in South America? *
Earthquake depth increases because the Nazca plate is subducting from the west coast toward the east coast of South America. So, the Nazca plate is becomes deeper under the continent of South America toward the east. Most earthquakes occur along the slab of oceanic crust that is subducting.
As you move away from the west coast of South America toward the east coast of South America what happens to earthquake depth?
Earthquake depth increases further east
Give one example of a rift eruption on land.
East African Rift system
How are subduction boundary eruptions different from rift eruptions? What causes the difference?
Explosive, mostly tephra because magma thickens and contains more gases
How does lava behave at rift eruptions?
Flows smoothly and fluidly
Where are the Rockys mountains and how did they form?
Further from convergent boundary on the continent because subduction was at a gentle slope
WHY does earthquake depth change?
Further moves down and more east because the origin is deeper
WHY are the Rockys farher away from the plate boundary than the Andes?
Gentle slope causes it to be inland
What is an example of continent to continent boundaries?
Himalayas
How did the Cascade Mountains form?
Juan de Fuca plate subducted under NA
Name two locations where rift eruptions occur in the ocean.
Mid-Atlantic ridge and East Pacific Rise
Where are the himalayas? How did they form?
Northern India
How do volcanic arcs form?
Ocean subducts
What type of crust is created at a rift zone?
Oceanic
What process occurs at deep ocean trenches?
Only convergence
New York State is located on which type of continental margin?
Passive margin
What is a basalt plateau? Give some examples.
Plateau formed by rift eruptions: Colombia, Karroo, Parana, Deccan
What do transform boundaries make?
San Andreas Fault and NO volcanoes
What type of boundary is at the west coast of Southern California?
San Andreas Fault and Rockies- Convergent and transform
Is earthquake depth shallow, intermediate or deep on the oceanic plate along the west coast in South America?
Shallow
What is columnar jointing?
Six-sided in lava flows
Explain how/why the Andes mts. formed in this area? What plates are involved?
South American and Nazca plates - Ocean to continent
Explain clearly WHY the Andes are located on the coast while the Rockies are located far inland.
The Andes Mountains are located right at the plate boundary and along the coast. The Rocky Mountains are located far inland and not at the plate boundary. This is because the Nazca plate is subducting at a much steeper angle under South America forming the Andes than the Pacific Plate is subducting under North America forming the Rockies.
Briefly but clearly explain the origin of the Cascade Mountains. *
The Cascade Volcanoes were formed by the subduction of the Juan de Fuca, Explorer and the Gorda Plate (remnants of the much larger Farallon Plate) under the North American Plate along the Cascadia subduction zone.
What Sea existed before the Atlantic Ocean existed?
The tethys sea
The tallest mountains are formed when...
There is a convergent boundary and after oceanic crust has subducted continental crust collides with continental crust
What forms from ocean to continent convergence?
Volcanic Arc
Name two landform features that form at subduction boundaries and give one example of each.
Volcanic Island chains: Philippenes, Japan, Aleutians; young mountain, Cascades, Andes
What forms from ocean to continent boundaries?
Volcanic arcs
How did the Sierra Nevada Mountains form?
When an oceanic plate subducted beneath NA plate
What's is true about earthquake foci depth in South America? *
as you move from west to east in South America earthquake depth increases
What geological features occur in the area of Iceland?
rift, hot spot, ridges, mid ocean ridge, divergence, rift valley
What is the shape of the volcanic cone that forms at subduction boundaries?
steep-sided
Difference between Andes and Rockys?
the Andes were formed from a plate that is subducting at a steep angle compared to the subduction zone that formed the Rocky Mountains.
How do aleutian islands form and what is it?
they formed from ocean to ocean collision and are an island arc
When does an island arc form?
when oceanic crust collides with oceanic crust
