Geologi Pantai

definisi pantai:
Tepi laut: pesisir
Perbatasan daratan dan laut / massa air lainnya dan bagian yang terpengaruh air laut tersebut
Daerah pasang-surut di pantai: antara pasang tertinggi dan surut terrendah
landai
Ada tiga bagian penyusun pantai:
Muka pantai (Beach face)
Berm
Backbeach

Three Major Parts of Beach
Beach-face:
zone of most active change
Its inclination may vary from a few degrees to as much as 30 degrees.
The slope is dependent on both grain size and wave energy which are themselves interdependent.
governing by wave height, wave period/length, and grain size of the particles.
Grain size is controlling percolation of water into the sand and the amount of water – through the beach sediments
Coarse sand with a high degree of percolation have steeper gradients than fine sand beaches
Berm:
forms at the top of the beach face.
on very flat beaches, the berm has a well-defined crest at the seaward edge.
As each wave moves up the beach face, energy is spent in a swash of water carrying sand upward.
Since part of the water returns through the beach sand, the backwash is reduced and sand is added to the berm at the crest.
Backbeach:
behind the berm varies in width and character.
The sands of the backbeach are generally fine-grained and well-sorted compared to the beach face.
The backbeach and dunes merge into one another and the line of demarcation may shift.

Coastal Geomorfology
Shepard Coastal Classification:
PRIMARY: The configuration of these coasts develops from nonmarine processes. The have not been significantly altered since the last rise of sealevel.
SECONDARY: Shaped primarily by marine agencies or by marine organisms. May or may not have been primary coasts before being shaped by marine forces