Plate Boundaries

1. Divergent Boundaries

• Definition: Areas where tectonic plates move apart.

• Characteristics:

  • Formation of new crust.

  • Associated with volcanic activity.

• Examples:

  • Mid-Atlantic Ridge.

2. Mid-Ocean Ridge

• Definition: An underwater mountain range formed by divergent tectonic plates.

• Characteristics:

  • Central rift valley.

  • Seafloor spreading occurs here.

• Significance:

  • Source of new oceanic crust.

  • Hydrothermal vents often found.

3. Continental Rift Valley

• Definition: A region where a continent is splitting apart.

• Characteristics:

  • Formation of rift valleys.

  • Volcanic activity common.

• Examples:

  • East African Rift.

4. Convergent Boundaries

• Definition: Areas where tectonic plates collide.

• Types:

  • Oceanic-Continental: Oceanic plate subducts under continental plate.

  • Oceanic-Oceanic: One oceanic plate subducts under another.

  • Continental-Continental: Both plates collide, leading to mountain formation.

4.1 Oceanic-Continental Plate Boundaries

• Characteristics:

  • Formation of trenches and volcanic arcs.

  • Example: Cascadia Subduction Zone.

4.2 Two Oceanic Plate Boundaries

• Characteristics:

  • Formation of island arcs.

  • Example: Mariana Islands.

4.3 Two Continental Plate Boundaries

• Characteristics:

  • Formation of mountain ranges.

  • Example: Himalayas (Indian and Eurasian plates).

5. Transform Fault Boundary

• Definition: Areas where tectonic plates slide past each other horizontally.

• Characteristics:

  • Earthquakes common due to friction.

  • No creation or destruction of crust.

• Examples:

  • San Andreas Fault.

Summary

• Divergent Boundaries: Plates move apart, creating new crust (e.g., Mid-Ocean Ridge).

• Convergent Boundaries: Plates collide, leading to subduction or mountain formation (e.g., Himalayas).

• **Transform

  Summary of Transform Faults

  Transform faults are geological features where two tectonic plates slide past each other horizontally. They are characterized by:

  • Movement: Lateral sliding, causing earthquakes.

  • Boundaries: Often found between divergent and convergent boundaries.

  • Examples: San Andreas Fault in California.

  • Geological Impact: Can create significant seismic activity and affect landforms.

  Transform faults play a crucial role in plate tectonics and the Earth's geological processes.

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