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Geography - Coggle Diagram

- - - - Tides
        
        Rise and fall in sea levels
        
        Waves reach higher parts of coast
      - Currents
        
        Large scale continuous movement of water
        
        Helps in sediment transportation
      - Geology
        
        Arrangement and composition of rocks
        
        Determines hardness and resistance to erosion
        
        Igneous rocks are harder, erode slower
        
        Sedimentary rocks are softer, erode faster
        
        Differentiated erosion occurs
        
        Determines how susceptible they are to solution
        
        Determines porosity (freeze-thaw/salt weathering)
        
        Lines of weaknesses
      - Types of ecosystems
        
        Mangroves
        
        Aerial roots trap sediments and reduce wave speed
        
        Sundarbans Mangrove Forest
        
        Coral reefs
        
        Natural barrier to help to slow down the speed and impact of waves on coastlines
        
        Great Barrier Reef
        
        Results in less erosion, more deposition
      - Human activities
      - Waves
        
        Types of waves
        
        Constructive waves
        
        Strong swash, weak backwash due to gently sloping coast
        
        Destructive Waves
        
        Weak swash, strong backwash due to steep coast
  - - - Wave refraction
        
        Waves converge on headlands and diverge on bays
        
        Results in:
        
        Notch
        
        Lines of weaknesses widen
        
        Cave
        
        Notch widens further
        
        Stack rocks, Pembrokeshire, UK
        
        Arch
        
        Cave completely erodes through headland, forming arch
        
        Stack rocks, Pembrokeshire, UK
        
        Stack
        
        Arch erodes and collapses, forming stack
        
        Stack rocks, Pembrokeshire, UK
        
        Stump
        
        Stack collapses, base of stack forms stump
        
        Stack rocks, Pembrokeshire, UK
      - Alternating layers of soft and hard rock undergo erosion. Soft rock erodes faster, forming bays. Hard rock forms headlands
        
        Bay: Barafundle Bay Beach, Pembrokeshire, UK
        
        Headland: Stack rocks Pembrokeshire, UK
    - - Hydraulic action widens crack on coast into notch. Notch deepens to form cave. Roof of cave collapses, forming cliff. Erosional processes undercut cliff, forming cave, repeating cycle
        
        Cliffs at Glamorgan, UK
    - - When there's an abrupt bend in the coastline, longshore drift carries sediments in the original direction for a certain length. When they are deposited in the sea, they form a ridge of sediments from the point where the coastline changes direction.
        
        Otherwise: spit
        
        Farewell spit, New Zealand
        
        Ridge meets land: tombolo
        
        Tauranga, New Zealand
    - - Zone of sediment deposition
        
        Finer sediment grains result in gentler gradient
        
        Changi Beach
  - - - Sea water reacts chemically with rocks and dissolves them, disintegrating them
    - - Rocks hit one another and become smaller, smoother and rounder
    - - Waves carrying rocks/sediments hurl them at coast. They knock and scrape coast weakening the surface, eventually undercuts cliff
    - - Air in cracks is compressed by waves, exerting pressure on cracks
  - - - Sediments transported horizontally along the coast
  - - - Beach nourishment
        
        Used on beach on coast of Sentosa, Singapore
        
        Expensive, time consuming, suffocating corals
      - Planting vegetation and stabilising dunes
        
        Vegetation planted on Sunset beach, Australia
        
        Takes time to take effect, storms, humans
      - Encouraging coral reef growth
        
        The Maldives encouraged coral reef growth by applying low-voltage to the corals
        
        Takes decades to take effect, growth may not be significant
      - Mangroves
        
        Restoration of Sundarbans Mangrove Forest, India
        
        Takes time to take effect, storms, humans
    - - Seawalls
        
        Isle of Wight, UK
        
        Absorbs wave energy, reflects incoming waves. Eventually undermines seawall, costly
      - Gabions
        
        Andaman coast, Thailand
        
        Absorbs wave energy well, costly, unsightly, easily corroded/damaged
      - Breakwaters
        
        Almeria, Spain
        
        Breaks force of oncoming waves, unsightly, uneven protection
      - Groynes
        
        Sandy Hook, New Jersey
        
        Stops longshore drift removing sediments, unsightly, expensive, downdrift side of groyne not protected
      - Tetrapods
        
        Hokkaido, Japan
        
        Dissipates wave energy, interlock, quick, unsightly, expensive
    - - Limit damaging activities
        
        Beaches at Port Philip, Australia fenced off because people trampled the vegetation holding the sand dunes together
      - Protect coastal resources
        
        Wakatobi national park, Indonesia marked off to prevent commercial shipping
      - Restrict development in areas prone to natural disaster
        
        Indonesian law restricts new farms and residences in low-lying coastal areas
  - - - Ecosystem services
        
        Coastal protection
        
        97% wave energy reduction, 84% wave reduction
        
        Housing 25% of all marine life
        
        Food and fishing
        
        Tourism/recreation
        
        Medicine
      - Ideal conditions for growth
        
        above 17C
        
        Average salinity/acidity
        
        Low turbidity
        
        10-60m depth for algae photosynthesis
        
        Strong wave action (more food/oxygen, less sedimentation suffocating corals
        
        Rocks for larvae to attach to
      - Threats
        
        Disease
        
        Climate change (acidification+temp->bleaching)
        
        Overfishing
    - - Ecosystem Services
        
        Coastal Protection
        
        Water filtration
        
        Tourism
        
        FIsheries
        
        Climate regulation
        
        Ecosystem services (US$800B)
        
        Wood
        
        Livelihoods of coastal populations
      - Threats
        
        Pollution (Clogging roots)
        
        Aquaculture
        
        Coastal development
        
        Climate change
        
        Agriculture
        
        Logging
- - - - All continents were part of a supercontinent, Pangaea. Parts of Earth's crust slowly drift across the liquid core over millions of years
    - - Early 20th century context
        
        Lack of evidence that we have now from technological advancements
        
        Unconventional ideas were not accepted unless there was undeniable proof
      - Cannot distinguish driving force
    - - Matching rock formations
        
        Giant mountain range through Greenland, Iceland, UK, Norway, Canada and America
      - Glacial evidence
        
        Glacial deposits found in Antarctica, Africa, S. America, India, Australia
      - Distribution of fossils
        
        Mesosaurus fossils in Brazil and Africa
      - Fit of continents
        
        Africa and S. America
  - - - Paleozoic
        
        Silurian
        
        Devonian
        
        Ordovician
        
        Carboniferous
        
        Mississippian
        
        Pennsylvanian
        
        Cambrian
        
        Permian
      - Mesozoic
        
        Triassic
        
        Jurassic
        
        Cretaceous
      - Late proterozoic
      - Cenozoic
        
        Tertiary
        
        Quarternary
  - - - Asthenosphere
      - Mantle
      - Lithosphere
        
        Coast
        
        Less dense continental crust
        
        Denser oceanic crust
        
        Upper mantle
- - - - Pressure on policy makers to be environmentally conscious
  - - - Spatial hierarchy
        
        Residential unit
        
        Neighbourhood
        
        Precinct
        
        Town
      - To cater to the needs of residents
      - Creating connections and synergies across areas.