How are sand spits formed?

Answer

Sand spits form after sudden changes in the shape of a coastline. This causes longshore drifts that deposit sediment in the direction of the drift, rather than along the coastline. Sand spits appear as fingers of land projecting from the coast.

Longshore drifts occur when prevailing winds blow at an angle to the coastline. The drifts carry sediment to the shore. When the shoreline suddenly changes direction the sediment continues to drift, eventually being deposited when currents become weaker. Wave refraction generates a hook in the shape of the spit. This hooked land area creates a shallow protected body of water. Salt marshes form within this protected body.

The continual erosion of sand spits combined with the continual deposition of sediment makes sand pits unstable land forms. Increased amounts of sediment may increase the rate of deposition behind the sand spit. When events such as storms create an imbalance between deposition and erosion, the shape of the sand pit can change dramatically. Sand pits that become large enough to completely block off a bay of water they are called bars. The water behind a bar is known as a lagoon. Many sand spits occur at the mouth of a river.

Q&A Related to "How are sand spits formed?"
It is basically when the waves or currents pull sand and rock into the same place everytime over a long period of time. This would make a great science project. For more information
http://www.ask.com/web-answers/Science/Nature/how_...
Sand spits form when elongated sandbars remain in place due to wave action along a shoreline. The spit can remain attached to the shore as an isthmus, or a bar can be separated to
http://wiki.answers.com/Q/How_are_a_sand_spit_and_...
Black sand beaches can be made up of two different types of sand. One is made by placer deposits and is composed of a heavy, glassy mixture of fine sands. This type of sand is also
http://www.ehow.com/info_8634407_black-sand-beache...
When lakes or stream beds dry out the sediment is exposed to the wind. A 10mph wind is
http://www.chacha.com/question/how-are-sand-dunes-...
Explore this Topic
A spit is the result of the ocean hitting the sand of a beach or shore. It is a accumulation of matter that can include: dirt, dead sea life, and other matter. ...
Sand is formed as a sedimentary material; loose grains of worn out and disintegrated rocks. The most common natural process of sand formation is weathering, this ...
Sand dollars are actually skeletons (also called tests) of a sea creature called a sea urchin. While they are alive, the sand dollars have spines on their tests ...
About -  Privacy -  Careers -  Ask Blog -  Mobile -  Help -  Feedback  -  Sitemap  © 2014 Ask.com