Beach profile Flashcards
what the beach sediment profile
the pattern of distribution of different sized or shaped deposited material
what is a berm?
a terrace on the beach that is formed in the backshore above the water level at high tide
-an existing berm can be moved up the beach by storms and spring tides and a new berm can develop and change the beach profile
-run parallel to the beach
what are beach ripples?
wave sculpted structure as waves travel across the surface if a body of liquid
-the waves cause water beneath the surface to circle around and around, generating oscillating flows that pick up sand grains and set them down
-this process eventually carves out troughs and grooves throughout the sandbed
what is a microfeature?
a small scale feature
e.g. ripples
what is a macrofeature?
a large scale feature
e.g. berms
what are runnels and ridges?
ridges are areas of the beach that are raised
runnels are dips/ troughs and are water filled
-formed due to the interaction of tides, currents, sediments and beach topography
-only form on shallow gradient beaches
-run along the coast length
what are cusps?
crescent-shaped indentations that form on beaches with mixed sand and shingle deposits
-form where there is a junction/ change between sand and shingle
-swash is concentrated in the small bay which forms the centre of the cusp
-wave refraction occurs on a small scale
what are off-shore bars?
ridges of sand or shingle that run parallel to the coast in an offshore zone
-form from eroded sediment by destructive waves and are carried seawards by backwash
-cannot be seen at low tide
-sediment is deposited at the boundary of offshore and nearshore zone, where the orbit of water particles ceases to reach the seabed, halting the transport offshore
relationship between the size of beach and energy absorbed
the bigger the beach the more energy the beach absorbs.
