The Full Wiki

More info on Feeder bluff

Feeder bluff: Wikis

Advertisements
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

Feeder Bluff located at Jefferson Beach in Kingston,WA

A feeder bluff is a coastal cliff or headland that feeds the beaches down current. As the waves approach the bluff, they erode away sediment which then gets carried along the coastline and deposited across other beaches. The majority of the wave energy is concentrated at the base of the bluff, where it is most accessible for the wave action.

The bluff will be more susceptible to erosion if the sediment is unconsolidated, and is found to be more resistant in crystalline rocks, like granite. The difference between the two is quite drastic, a difference of thousands of cm/year to less than 1 cm/year of retreat respectively. Rocks that are heavily fractured are also very likely to suffer from excess erosion because the water can flow between the cracks to speed up the process. The bluff will retreat towards land as the erosion processes continue.

Contents

Types

Evidence of erosion causing mass movement at Jefferson Beach in Kingston, Washington

There are two main types of feeder bluff erosion, defined by the patterns of wave energy. These patterns are also highly variable, even within themselves. The first type consists of erratic erosion patterns, light waves with intermittent large storms, those tend to be rocky slopes. The majority of the erosion that occurs happens during storms. The high energy storm waves have more power to take sediment away and deposit it along the coast with the long shore drift. The high energy of a single storm has the ability to take up to 5 to 30 m of the bluff into the water with it.

The second type of bluff is adding sediment at a rate nearly equal to the rate of erosion. In this case, the sediment load is balanced and between storms. There will almost always be a talus, mass of eroded material, at the base of the bluff. This talus will help protect the base of the cliff from further erosion as long as it is present.

Human Interference

The feeder bluffs are an important contribution to the coastal system in order for it to maintain its balance. The sediment that is removed from the feeder bluff is carried with the long shore drift and deposited, contributing to the building and upkeep of those beaches. Houses have been built on the tops of some bluffs(see images), and homeowners often try to protect their homes. It has become common for people to create barriers of large rock or cement to protect bluffs from erosion. Bluffs that are protected by human additions remove the sediment source for the nearby beaches. As a result, the beaches lose their source and will erode and deteriorate back until the beach is lost. The people living in those regions will have their home and their bluff for a while, but their beaches will be lost in the process.

References

  • Easterbrook, Don J. (1999). Surface Processes and Landforms (2nd Edition ed.). Upper Saddle River, N.J.: Prentice Hall. ISBN 978-0-13-860958-0.  

External links

Advertisements

Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message