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Pablo Fraile Jurado

Pablo Fraile Jurado

1. Processes and landforms. Pablo Fraile Jurado 2. The andalusian case. Pepe Ojeda Zújar 3. Coast of the world. Miriam Fernández Núñez

Introduction ◦ Structure of the Earth and where the sea is. ◦ Physiography of the ocean floor

Processes in the coast ◦ Waves ◦ Tides ◦ Sea levels ◦ Other processes ◦ Geological structure of the ebmerged areas

Landforms ◦ Exposed landforms ◦ Protected landforms

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Middle scale phenomena: http://www.stumbleupon.com/su/2yfJOd/primaxstudio.com/stuff/scale_of_universe/

Structure of the Earth and where the sea is

Structure of the Earth ◦ Inner core

◦ Outer core

◦ Mantle

◦ Crust

http://www.stumbleupon.com/su/2yfJOd/primaxstudio.com/stuff/scale_of_universe/

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71% of crust is convered by ocean waters

70% of the landmasses are in the Hnorthen Hemisfere

Continental margins ◦ Continental plain

◦ Continental slope

◦ Continenal rise

Deep Ocean basins ◦ Abyssal plains

◦ Deep-sea trenches

◦ Seamounts

Midocean ridge

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Processes ◦ Waves ◦ Tides ◦ Sea level ◦ Storms ◦ Hardness

Landforms ◦ Exposed landforms Beaches

Profiles Sand budgets

Barrier eaches Spits Cliffed coasts Deltas

◦ Protected landforms Estuaries Marshes

Waves ◦ Mainly, 2 types of waves: Wind waves Swell waves (+capilarity waves)

◦ Factors Fetch Wind speed Water depth

◦ Characteristcs Height Lenght Speed Period Propagation direction

Wind waves

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Swell waves

Wave definition

Types of waves ◦ Wind waves ◦ Swell waves ◦ Capilarity waves

Wave propagation ◦ Deep waters ◦ Shallow waters

Refraction Diffraction Reflection; http://www.youtube.com/watch?v=NEVtNJ_tcfg

http://www.youtube.com/watch?v=NEVtNJ_tcfg

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Wind waves: http://www.youtube.com/watch?v=um5ahIZx87A

Swell waves: http://www.youtube.com/watch?v=rnKEdmX6qco

Tsunami in deep sea: http://www.youtube.com/watch?v=OdhfV-8dbCE

Tsunami in the coast: http://www.youtube.com/watch?v=w3AdFjklR50

http://www.youtube.com/watch?v=um5ahIZx87Ahttp://www.youtube.com/watch?v=rnKEdmX6qcohttp://www.youtube.com/watch?v=OdhfV-8dbCEhttp://www.youtube.com/watch?v=OdhfV-8dbCEhttp://www.youtube.com/watch?v=OdhfV-8dbCEhttp://www.youtube.com/watch?v=w3AdFjklR50

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Tides ◦ What tides are.

◦ 3 types of tides according their ranges:

Macro. http://www.youtube.com/watch?v=u3LtEF9WPt4

Meso.

Micro

◦ 2 types of periodicity

Diurnal

Semi-diurnal

◦ http://dusk.geo.orst.edu/oceans/PPT/TidalCycleV2.html

http://www.youtube.com/watch?v=u3LtEF9WPt4http://dusk.geo.orst.edu/oceans/PPT/TidalCycleV2.html

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Sea level and geoid

Absolute and relative mean sea level changes

Mean sea level in the geological past

Present and future mean sea level changes

REAL SEA LEVEL SHAPE

Pablo Fraile Jurado

Departamento de Geografía Física y A.G.R. - Universidad de Sevilla

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+42 m

+36 m

MEAN SEA LEVEL SHAPE

Los mapas topográficos se elaboran considerando estas diferencias.

Pablo Fraile Jurado

Departamento de Geografía Física y A.G.R. - Universidad de Sevilla

MEAN SEA LEVEL SHAPE

Los mapas topográficos no consideran estas diferencias, que localmente pueden ser de magnitud media (hasta 50 cm),

Pablo Fraile Jurado

Departamento de Geografía Física y A.G.R. - Universidad de Sevilla

CAMBIOS DEL NIVEL DEL MAR

Pablo Fraile Jurado

Departamento de Geografía Física y A.G.R. - Universidad de Sevilla

http://upload.wikimedia.org/wikipedia/en/4/44/Phanerozoic_Sea_Level.png

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CAMBIOS DEL NIVEL DEL MAR

Pablo Fraile Jurado

Departamento de Geografía Física y A.G.R. - Universidad de Sevilla

Other processes: ◦ Storms

◦ Wind

◦ Tsunamis

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Geological structure of the coast ◦ Hardness / softness of materials

Hard rocks

Soft rocks

Sand

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Geological structure of the coast ◦ Hardness / softness of materials

Hard rocks

Soft rocks

Sand

Vegetation

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Exposed coasts ◦ Wave as main factor ◦ Relationship between energy input from waves and

the land: Balanced: beaches.

Positive: deltas

Negative: cliffs

Protected Coasts ◦ Controlled by Tides Macro and mesotidal coasts: marshes

Microtidal coasts: lagoons

Beaches ◦ What a beach is.

◦ Dissipating energy

◦ Profiles in beaches

◦ Sand budgets

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Barrier beaches ◦ Beaches controlled by transversal dynamics

◦ Sediment budgets from rivers

◦ Not only barrier islands

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Spits ◦ Beaches controlled by longitudinal dynamics

◦ Sediment budgets from… elsewhere

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Deltas ◦ Controlled by the sediment suplies from rives

◦ Neutral or positive balance between the supplies and the erosion.

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Cliffed coasts ◦ Eroding coasts

◦ Types of cliffs:

Depending on the size

Depending on the hardness

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Exposed coasts ◦ Wave as main factor ◦ Relationship between energy input from waves and

the land: Balanced: beaches. Positive: deltas

Negative: cliffs

Protected Coasts ◦ Controlled by Tides Macro and mesotidal coasts: marshes

Microtidal coasts: lagoons

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And what if waves are not the key factor? ◦ Tides become into the main factor in mesotidal and

macrotidal coasts.

◦ Marshes

Salt marshes

River marshes

◦ Lagoons

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Processes ◦ Waves ◦ Tides ◦ Sea level ◦ Storms ◦ Hardness

Landforms ◦ Exposed landforms Beaches

Profiles Sand budgets

Barrier eaches Spits Cliffed coasts Marshes Deltas

◦ Protected landforms Marshes Estuaries