Plate Tectonics

Plate Tectonics- movement of the plates over Earth’s surface.

Theory of Plate tectonics- is the theory that can explain the tectonic and geologic processes that occur on Earth.

Convection Current- causes the plates to move

The German  geophysicist Alfred Wegener found that our continents could fit to each other like a jigsaw puzzle.

Earth’s Crust and the uppermost part of the mantle is the Lithosphere

The tectonics float above the hotter portion of the mantle called the Asthenosphere. It is an area where two plates meet is called Plate Boundary.

2 Types of Earth's Layer

Mechanical Layer

  • Lithosphere
  • Asthenosphere
  • Mesosphere
  • Outer Core
  • Inner Core

Compositional Layer

  • Crust
  • Mantle
  • Core

Subduction- an event which the sub of rock thrusts into the mantle.

Trench- a depression in the seafloor produced by subduction process.

Convergent Boundary- is where the two plates moves towards each other

Divergent Boundary- is where the two plates move apart

Transform- the two plates slip past each other

OCEANIC TO OCEANIC - When the two plates converge the denser plate is pushed under the lighter one. An Island Arc is formed as a result of oceanic-oceanic

OCEANIC TO CONTINENTAL- The denser oceanic plate will go under the continental plate. A volcanic arc is formed as a result of oceanic-continental

CONTINENTAL TO CONTINENTAL- When the two continental plates collide, they have a tendency to rise and collide with each other because of their low density. A mountain range is formed through continental-continental, the best example of it is the Mount Himalayas in South Asia

Volcano can form in convergent boundary when the two plates collide the denser plate sinks, or subducts into the mantle and in Divergent Boundary the two plates spread apart

PHIVOLCS -Philippine Institute of Volcanology and Seismology

Active Volcanoes- that have a history of eruption

Inactive Volcanoes- those who have none, also have a signs of physical change due to weathering and erosion.

Potentially Active Volcanoes- are young looking and have no record.

Fault- is a fracture or a crack found in the crust, example  of it is the San Andreas Fault in California USA

The 3 types of Fault

Normal Faults- have hanging walls that move down relative to the footwall

Hanging Wall- is the block immediately above the fault surface

Footwall- lies below the fault surface

Reverse Fault- or also called Thrusts Fault it occurs when the hanging wall moves up relative to the footwall

Strike Slip Fault- are those where the dominant displacement occurs along the strike of the fault.