Types of Plate Boundaries

<<<<-2a ul>

Convergent plate boundaries

When two plates move towards each other, they can either collide or one plate can slide under the other. If the plates collide, the landmasses on either side of the boundary will be pushed together. This can cause mountains to form. If one plate slides under the other, it is called subduction. Subduction zones are often associated with VolcanoesVolcanoes and earthquakes.

The Andes Mountains in South America are an example of a convergent plate boundary. The Nazca Plate is moving eastward and is being subducted under the South American Plate. This subduction is causing the Andes Mountains to grow taller.

The Mariana Trench in the Pacific Ocean is another example of a convergent plate boundary. The Pacific Plate is moving eastward and is being subducted under the Mariana Plate. This subduction is causing the Mariana Trench to become deeper.

Divergent plate boundaries

When two plates move away from each other, new crust is created. This is because the magma from the Earth’s mantle rises to the surface and cools to form new rock. Divergent plate boundaries are often found in the middle of the ocean.

The Mid-Atlantic Ridge is an example of a divergent plate boundary. The North American Plate and the Eurasian Plate are moving away from each other on either side of the ridge. This movement is causing the Atlantic Ocean to widen.

The East African Rift is another example of a divergent plate boundary. The African Plate and the Arabian Plate are moving away from each other on either side of the rift. This movement is causing the Red Sea and the Gulf of Aden to form.

Transform plate boundaries

When two plates slide past each other, they can either grind against each other or one plate can slip past the other. Transform plate boundaries are often found along faults.

The San Andreas Fault in California is an example of a transform plate boundary. The Pacific Plate and the North American Plate are moving past each other on either side of the fault. This movement is causing the San Andreas Fault to grow longer.

The Alpine Fault in New Zealand is another example of a transform plate boundary. The Pacific Plate and the Australian Plate are moving past each other on either side of the fault. This movement is causing the Alpine Fault to grow longer.

Plate tectonics

The theory of plate tectonics explains how the Earth’s surface is constantly moving. The theory states that the Earth’s crust is made up of tectonic plates that are constantly moving. These plates can move towards, away from, or past each other. The way that the plates move creates three types of plate boundaries: convergent, divergent, and transform.

Plate tectonics is a very important theory because it helps us to understand the Earth’s geology. It also helps us to understand how earthquakes and volcanoes form.
Convergent plate boundaries

• What happens at a convergent plate boundary?
  At a convergent plate boundary, two tectonic plates collide. The type of boundary that forms depends on the relative densities of the two plates. If one plate is denser than the other, it will subduct beneath the less dense plate. This process is called subduction.

• What are the different types of convergent plate boundaries?
  There are three types of convergent plate boundaries: oceanic-oceanic, oceanic-continental, and continental-continental.

• What happens at an oceanic-oceanic convergent plate boundary?
  At an oceanic-oceanic convergent plate boundary, the denser oceanic plate subducts beneath the less dense oceanic plate. This process forms a deep-sea trench. The subducting plate melts and forms magma, which rises to the surface and erupts to form volcanoes.

• What happens at an oceanic-continental convergent plate boundary?
  At an oceanic-continental convergent plate boundary, the denser oceanic plate subducts beneath the less dense continental plate. This process forms a deep-sea trench. The subducting plate melts and forms magma, which rises to the surface and erupts to form volcanoes. The continental plate is too thick to be subducted, so it is pushed up and forms a mountain range.

• What happens at a continental-continental convergent plate boundary?
  At a continental-continental convergent plate boundary, the two plates collide and crumple together. This process forms a mountain range.

Divergent plate boundaries

• What happens at a divergent plate boundary?
  At a divergent plate boundary, two tectonic plates move away from each other. This process creates new crust as magma rises to the surface and cools.

• What are the different types of divergent plate boundaries?
  There are two types of divergent plate boundaries: mid-ocean ridge and rift valley.

• What happens at a mid-ocean ridge?
  At a mid-ocean ridge, two tectonic plates move away from each other. This process creates new crust as magma rises to the surface and cools. The mid-ocean ridge is the longest mountain range on Earth.

• What happens at a rift valley?
  At a rift valley, two tectonic plates move away from each other. This process creates new crust as magma rises to the surface and cools. The rift valley is a long, narrow depression in the Earth’s surface.

Transform plate boundaries

• What happens at a transform plate boundary?
  At a transform plate boundary, two tectonic plates slide past each other horizontally. This process can cause earthquakes.

• What are the different types of transform plate boundaries?
  There are two types of transform plate boundaries: ridge-transform and fault-transform.

• What happens at a ridge-transform?
  At a ridge-transform, a mid-ocean ridge is offset by a transform fault. This type of boundary is common in the ocean.

• What happens at a fault-transform?
  At a fault-transform, a fault line is offset by a transform fault. This type of boundary is common on land.

Conservative plate boundaries

• What happens at a conservative plate boundary?
  At a conservative plate boundary, two tectonic plates slide past each other without creating or destroying any crust. This process can cause earthquakes.

• What are the different types of conservative plate boundaries?
  There are two types of conservative plate boundaries: strike-slip and oblique-slip.

• What happens at a strike-slip?
  At a strike-slip boundary, two tectonic plates slide past each other horizontally. This type of boundary is common in the San Andreas Fault.

• What happens at an oblique-slip?
  At an oblique-slip boundary, two tectonic plates slide past each other horizontally and vertically. This type of boundary is common in the Himalayas.

• At which type of plate boundary do two plates collide?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (CC) Transform plate boundary
  (D) Conservative plate boundary

• At which type of plate boundary do two plates move apart?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• At which type of plate boundary do two plates slide past each other?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• At which type of plate boundary is there no relative movement between the plates?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• Which of the following is a result of convergent plate boundaries?
  (A) Mountain ranges
  (B) Trenches
  (C) Earthquakes
  (D) All of the above

• Which of the following is a result of divergent plate boundaries?
  (A) Mid-ocean ridges
  (B) Rift valleys
  (C) Hot spots
  (D) All of the above

• Which of the following is a result of transform plate boundaries?
  (A) Fault lines
  (B) Earthquakes
  (C) Trenches
  (D) None of the above

• Which of the following is a result of conservative plate boundaries?
  (A) No obvious features
  (B) Fault lines
  (C) Earthquakes
  (D) None of the above

• The Andes Mountains are an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The Mid-Atlantic Ridge is an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The San Andreas Fault is an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The East African Rift Valley is an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The Mariana Trench is an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The Hawaiian Islands are an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary

• The Iceland Plateau is an example of which type of plate boundary?
  (A) Convergent plate boundary
  (B) Divergent plate boundary
  (C) Transform plate boundary
  (D) Conservative plate boundary