Coastal Processes ~ erosion, transport & deposition 12.1 CA NC
Erosion http://geobytesgcse.blogspot.com/2007/08/coastal-processes-erosion-transport-and.html
Erosional processes Abrasion = continuous tumbling reduces rock to sand grains Solution = salt dissolves some of the rock Scouring = wave swirls at base of cliff & loosens rock
Erosion Erosional processes in action http://www.bbc.co.uk/schools/gcsebitesize/geography/coastal/coastalprocessesrev3.shtml
Erosional Features Sea cliff Sea cave Sea arch Sea stack Terrace
Sea cliff Navassa Island, Caribbean Sea Forms when waves erode rock http://coastal.er.usgs.gov/navassa/photos/ep/hike/CliffE.jpg
Sea cave Short Sands Beach, Oregon Hole eroded at base of cliff http://web.cecs.pdx.edu/~walpole/pics/kayak/falcon/cave3.jpg
Sea arch Hawaii Sea cuts through headland http://upload.wikimedia.org/wikipedia/commons/e/eb/SeaArchHawaii.jpg
Sea stack County Mayo, Ireland Isolated column of rock http://ts1.mm.bing.net/images/thumbnail.aspx?q=1023555809064&id=45685568345e0ba48cec1d6807ea14ba&url=http%3a%2f%2fwww.visualphotos.com%2fphoto%2f2x4004071%2fdoonbristy_sea_stack_downpatrick_head_ballycastle_1813001.jpg
Sea terraces Haiti Flat platforms at water height http://www.amishkin.com/wp-content/uploads/2010/03/P1000346-Large.jpg
Features
Transport Material eroded by the sea is moved along the beaches.
Longshore drift Longshore drift illustration http://www.bbc.co.uk/schools/gcsebitesize/geography/coastal/coastalprocessesrev4.shtml Waves approach beach at angle Sand moves in zig zag motion Creates longshore current Current keeps sand moving until it hits a change or structure, then it drops out.
Longshore drift diagram http://cgz.e2bn.net/e2bn/leas/c99/schools/cgz/accounts/staff/rchambers/GeoBytes%20GCSE%20Blog%20Resources/Images/Coasts/Longshore_Drift.jpg
Deposition Sand deposits form where amount of rock moving toward shore is greater than amount moving away.
Depositional Features Beach Lagoon Tombolo Barrier island
Beach Emerald Isle, NC http://www.tripadvisor.com/LocationPhotos-g49113-Emerald_Isle_North_Carolina.html
Lagoon Vegetation is red; water is blue (satellite image)
Tombolo Bar that extends out into ocean, but remains connected to mainland. web.macam.ac.il web.macam.ac.il
Barrier Island http://www.frf.usace.army.mil/outerbanksaerialflight/Index.htm
Barrier Islands Occur on east coast of USA Isolated dunes become islands Parallel to shore Associated features: Sound (also called bay or lagoon) Tidal inlets Tidal flats Estuaries
HUMAN EFFECTS ON COASTLINES
Homework Read pages 342 - 347
Output Draw a block diagram of the east coast and include the features of the beaches. Draw a block diagram of the west coast and include the features of the beaches.