DAY 1 Terrestrial Env' Coastal Geomorphology Ian Elliot

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COASTAL GEOMORPHOLOGY
NORTHERN DEVELOPMENT TASKFORCE Environment
Experts Working Group Presentation Ian Eliot -
July 2008
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Tasks

• 1. Analyse, classify and map the coastal
  geomorphology of four locations, and consider the
  characteristics of each area relative to the
  coastal landforms of the surrounding region
• 2. Provide
• (a) information on the relative stability of the
  coastline with regard to historical and current
  relative rates and processes for erosion and or
  deposition of sediment associated with the
  location and
• (b) indicate how the location is likely to
  respond in extreme natural events, particularly
  cyclonic conditions storm surge and extreme
  rainfall events.

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Approach

• The approach adopted was to undertake a
  preliminary assessment of potential environmental
  change following steps recommended by the
  National Committee for Coastal and Ocean
  Engineering for assessment of coastal
  vulnerability to climate change (NCCOE, 2004)
• It involves
• 1. Identification of primary variables
• These are the driving forces affecting change
  and include fluctuation in sea level, tides,
  severe weather conditions, and the wave regime
• 2. Determination of landscape components
• Secondary process variables, such as sediment
  transport, operate on large landscape components
  such as sandy cliffs, beaches, barrier dunes,
  tidal creeks, mangals and mudflats.
• 3. Estimation of potential relationships between
  the primary variables and the landscape
  components
• Describe any apparent evidence for impacts of
  primary variables on the large landscape
  components establish potential relationships
  between them.

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Interrelationships
PRIMARY VARIABLES
GEOLOGICAL STRUCTURE
SEDIMENTS
SECONDARY VARIABLES
LANDFORMS
Morphodynamic System
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Primary Variables
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Primary Variables

• The National Committee on Coastal Engineering
  (2004) lists the primary (key) variables as
  follows
• Mean Sea Level
• Ocean Currents
• Ocean Temperature
• Wind Climate
• Wave Climate
• Rainfall Runoff
• Air Temperature
• Blue text indicates those used in assessment of
  potential coastal change.

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Geological Structure
Packer Island
Perpendicular Head
Quandong to Coulomb Point
Gourdon Bay
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Relationships Primary Variables Landforms
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Packer Island
Rock bar sand flats
Cliffs rock platforms
Washover channel fan
Chile Creek platform
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Packer Island
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Perpendicular Head
NORTH HEAD
PERPENDICULAR HEAD
Middle Lagoon
Emeriau Point Chimney Rocks
North Head Tappers Lagoon
Embalgun
Weedong Lagoon
Tappers Lagoon
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Perpendicular Head
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Coulomb Point to Quandong Point
South of Coulomb Point
North of James Price Point
Coulomb Point
Quandong Point
James Price Point - erosion
James Price Point - dunes
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Coulomb Point to Quandong Point
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Gourdon Bay
SW Cape Latouche Treville
Wrack deposit Port Smith
Extension of tidal creek
Gourdon Bay view SE
Cape Du Boulay - erosion
Cape Du Boulay geology
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Gourdon Bay
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Thanks for your attention