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• Endogenic Processes


  Processes that originate from within the Earth
• Endogenic Processes


  • Volcanism
  • Deformation
  • Metamorphism
  • Earthquake
• Magma


  Molten rock within the Earth's crust and mantle
• Plate Boundaries


  • Divergent boundary
  • Convergent boundary
  • Transform boundary
• Plate Tectonics


  1. Divergent boundary

  2. Convergent boundary

  3. Transform boundary
• Divergent boundary


  • Seafloor expansion occurs
  • Plates move away from each other
  • Creates new plate material
  • Creates normal faults
• Mid-ocean ridge


  • Largest source of oceanic lava
  • Divides the Americas from Africa
• Rift zones


  • Where continents begin to stretch, break apart, and expand over time
  • Form volcanoes through expansion
  • Example: East Africa Rift System
• Convergent boundary


  • Plates collapse and volcanic arcs are made
  • Plates move towards each other
  • Subduction occurs
  • Creates reverse faults
• Ocean-ocean plate convergence


  • Denser oceanic plate subducts to the less dense oceanic plate, creating island arcs
• Ocean-continent convergence


  • Oceanic plate automatically subducts, creating continental volcanic arcs
• Continent-continent convergence


  • Less dense continental plate rises above the denser continental plate, creating collision mountain belts
• Trenches


  • Indications of convergent boundaries
• Transform boundary


  • Plates slide past each other, forming strike-slip faults
  • Retains all its materials and only breaks the crust
• Mid-ocean ridges


  • Consist of short segments linked by transform faults oriented perpendicularly to the ridge's axis
• San Andreas Fault


  • Example of a transform fault
• Plate Movement Drivers


  • Mantle Convection
  • Slab Pull
  • Ridge Push
• Wilson Cycle


  Theory proposed by John Tuzo Wilson to correlate plate movement with the Earth's timeline
• Wilson Cycle


  1. Continent Rifting

  2. Oceanic Basin and Crust Development

  3. Passive Margin Cooling and Sedimentation

  4. Volcanic Mountain Belt Formation

  5. Subduction Welding

  6. Continental Collision

  7. Orogenesis
• Earth has Panthalassa surrounding Pangaea, which also contains the large landmasses of Laurasia and Gondwana


  ~237 MYA
• Pangaea begins to break apart, forming vague landmasses that will eventually become the modern-day continents, losing Laurasia in the process


  ~195 MYA
• Continental plates began to have definite boundaries and started to drift further away


  ~152 MYA
• Continental Collision


  Crustal roots are formed and build mountains
• Orogenesis


  Exogenic and endogenic processes weather down mountains, which allows the crust to restart the entire cycle
• Notable formations


  • South America
  • North America
  • Eurasia
  • Africa
  • India
  • Antarctica
  • Australia
• Seafloor Spreading


  Magma oozes up from the Earth's interior towards the surface through the mid-oceanic ridge, solidifying into new seafloor material. This pushes apart the older seafloor, going down into deep trenches—a clear indication of subduction
• Magnetic field


  • Materials such as basalt contain small magnetic minerals (e.g., magnetite and hematite) exhibit negative anomaly, and the magnetic poles of the Earth remain constant while the seafloor materials always change positions
• Age dating


  • Scientists developed age dating techniques and used it alongside magnetic studies, noting that the age and magnetic signatures of the rocks vary systematically on either side of the ridge
• Age and thickness of sediments

  • Older seafloor sediments should be thicker than the younger and newly-formed seafloor sediments
• Continental Drift


  The early Earth was once a supercontinent named Pangaea, being surrounded by a superocean named Panthalassa. This supercontinent eventually broke up and moved away from each other, forming the continents
• Evidence for Continental Drift

  • The Fit of Continental Shorelines
  • Distribution of Glacial Sediments
  • Paleoclimate
  • Fossil Distribution
  • Rock Distributions
• The southwestern coastlines of Africa fit well with the eastern coasts of South America and the southeast portion of North America
• Sediments and rocks formed during the late Paleozoic era, including the imprinted striations of the rocks, can be found in Africa, Antarctica, Australia, India, and South America
• Despite being in a polar region, the supercontinent Pangaea has other areas exposed to the equatorial region, allowing tropical flora and fauna to flourish and produce coal
• Fossils of similar organisms located in continents that are just too far apart for them to travel in the past, particularly the fossils of Glossopteris, Cynognathus, Lystrosaurus, and Mesosaurus, can be explained by the once-tight knit form of Pangaea
• Similar rock materials are found in continents that are very far apart, which can be explained by the materials being built on a single landmass, Pangaea