Monday 28 January 2013

Beach Wallpaper

Source(google.com.pk)
Beach Wallpaper Biography

A beach is a landform along the shoreline of an ocean, sea, lake or river. It usually consists of loose particles which are often composed of rock, such as sand, gravel, shingle, pebbles or cobblestones. The particles comprising the beach are occasionally biological in origin, such as mollusc shells or coralline algae.
Wild beaches are beaches which do not have lifeguards or trappings of modernity nearby, such as resorts, camps and hotels. They are sometimes called undeclared, undeveloped or undiscovered beaches. Wild beaches can be valued for their untouched beauty and preserved nature. They are most commonly found in less developed areas including, for example, parts of Puerto Rico, the Dominican Republic, Thailand, the Philippines, and Indonesia.
Beaches typically occur in areas along the coast where wave or current action deposits and reworks sediments.
Contents  [hide]
1 Overview
2 Beach formation
3 Beach wildlife
4 Beaches and recreation
4.1 Artificial beaches
4.2 Restrictions on access
5 See also
6 References
7 Further reading
8 External links
[edit]Overview

The four sections of most beaches.
1. Swash zone: is alternately covered and exposed by wave run-up.
2. Beach face: sloping section below berm that is exposed to the swash of the waves.
3. Wrack line: the highest reach of the daily tide where organic and inorganic debris is deposited by wave action.
4. Berm: Nearly horizontal portion which stays dry except during extremely high tides and storms. May have sand dunes.
Although the seashore is most commonly associated with the word beach, beaches are found by lakes and alongside large rivers, as well as by the sea or oceans.
Beach may refer to:
small systems where rock material moves onshore, offshore, or alongshore by the forces of waves and currents; or
geological units of considerable size.
The former are described in detail below; the larger geological units are discussed elsewhere under bars.
There are several conspicuous parts to a beach which relate to the processes that form and shape it. The part mostly above water (depending upon tide), and more or less actively influenced by the waves at some point in the tide, is termed the beach berm. The berm is the deposit of material comprising the active shoreline. The berm has a crest (top) and a face — the latter being the slope leading down towards the water from the crest. At the very bottom of the face, there may be a trough, and further seaward one or more long shore bars: slightly raised, underwater embankments formed where the waves first start to break.
The sand deposit may extend well inland from the berm crest, where there may be evidence of one or more older crests (the storm beach) resulting from very large storm waves and beyond the influence of the normal waves. At some point the influence of the waves (even storm waves) on the material comprising the beach stops, and if the particles are small enough (sand size or smaller), winds shape the feature. Where wind is the force distributing the grains inland, the deposit behind the beach becomes a dune.
These geomorphic features compose what is called the beach profile. The beach profile changes seasonally due to the change in wave energy experienced during summer and winter months. The beach profile is higher during the summer due to the gentle wave action during this season. The lower energy waves deposit sediment on the beach berm and dune, adding to the beach profile. Conversely, the beach profile is lower in the winter due to the increased wave energy associated with storms. Higher energy waves erode sediment from the beach berm and dune, and deposit it off shore, forming longshore bars. The removal of sediment from the beach berm and dune decreases the beach profile.
The line between beach and dune is difficult to define in the field. Over any significant period of time, sand is always being exchanged between them. The drift line (the high point of material deposited by waves) is one potential demarcation. This would be the point at which significant wind movement of sand could occur, since the normal waves do not wet the sand beyond this area. However, the drift line is likely to move inland under assault by storm waves.[1]
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper
Beach Wallpaper

No comments:

Post a Comment