Resultant Features of Wind Deposition



The following are the Resultant Features of Wind Deposition:

Sand Dunes are Low ridge of sand accumulated by wind deposition.

Sand Dunes are Low ridge of sand accumulated by wind deposition

Types of sand dunes

Barchans

this is a crescent-shaped mound of sand in a desert.

barchans forming process

  • Sand accumulates around an obstacle lying on the path of the wind.
  • Deposition continues making the mound grow bigger.
  • The wind blows sand over the leeward side creating a smooth gentle windward slope.
  • Wind eddies act on the leeward slope, making it to be steep and concave.
  • Sidewind moves the sand grains on the sides forward creating the two edges which are curved e.g. in the Sahara and Arabia Desert.




Characteristics of sand dunes

  • Crescent/moon shaped
  • Smooth gentle windward slope
  • Steep concave leeward slope
  • Horns or 2 curved edges
  • Occurs individually or in groups

ii) Seif Dunes

this is Ridge shaped mounds of sand lying parallel to the path of the prevailing wind.



seif dunes forming process

  • The wind blows between barchan dunes.
  • Wind eddies move sand towards the sides.
  • Sand accumulates on the sides resulting in ridge-shaped mounds e.g. in the Namib Desert.

iii) Transverse or Wake Dunes

These are Wave mounds of sand in a desert that lie at right angles to the prevailing wind.

They are formed in the following process




  • Less strong winds blow over sand from one direction.
  • The wind concentrates larger grains of sand into a series of transverse ridges.
  • Wind may continue pushing the sand causing it to accumulate on the leeward side to form a wake dune e.g. in W. Sahara.

Drass

this is the biggest sand feature in a desert with a surface resembling a plateau and with a height of up to 200m. Barchans and Seif dunes may form on such features e.g. in the E. Sahara desert.



Loess

These are Fertile soils with a great thickness of about 100 m formed from the deposition of dust from deserts.

  • Dust from deserts is carried beyond to wet areas.
  • Its washed down by rain causing its deposition.
  • It accumulates into layers.
  • Deposition continues, and the layers are compacted forming sedimentary rocks.




  • The sedimentary rocks wither to form fertile soils which favour cultivation e.g. Temperate lands of Europe along the Rhine valley from Sahara dust and along Huang He valley in N. China from the dust of the Gobi Desert.

READ MORE

Types of Glacial Deposits and Causes of Glacial Deposition



Material carried by the glacier is called a moraine.

Material carried by the glacier is called a moraine

Types of Moraine

  • Ground/sub-glacier moraine – load carried at the base of the glacier.
  • Englacial moraine – load within the glacier.
  • Lateral moraine – load carried at the sides of the glacier.
  • Medial moraine – load carried in the centre of the valley by a glacier.
  • Terminal/recessional moraine – load deposited at the point where a glacier melts.

Types of Glacial Deposits/Drift:




Till – directly deposited by ice on melting in unstratified manner.
Fluvial – materials deposited by water from the melting ice in stratified manner.

Causes of Glacial Deposition

  • Amount of glacial drift When ground moraine is too much the glacier glides over it leaving it behind.
  • Weight of glacier When more ice is added to a stationary glacier pressure is exerted at the base causing melting and the material which was embedded in the ice is dropped.



  • Climatic change During summer and spring ice melts depositing some materials the glacier was carrying.
  • Friction beneath the ice Friction between ice and surface reduces ice speed causing heavy materials to be deposited beneath ice sheets.
  • Slope Lowlands allow glacier to accumulate a lot of materials which are finally deposited by melting ice.

READ MORE

Marketing of Tea in Kenya



Some tea is consumed locally and a huge amount is sold on the international market.

Major marketer is K.T.D.A.

Functions of KTDA

  • Collection of tea from buying centers.
  • Processing of tea.
  • Providing farmers with inputs such as fertiliser.
  • Sensitizes farmers on high-quality production of tea.




  • Facilitates the sale of tea at the best possible prices.
  • Ensures prompt collection of payment from all tea buyers.
  • Promotion of tea with the aim of expanding market share.

Outlets through Which KTDA Markets Tea

  • Factory door sale of tea in polythene bags to farmers accounting for 3% of sales.
  • Through Mombasa auction where it exported to other countries such as Britain, France Afghanistan. It accounts for 75% of sales.
  • Dealing directly with interested buyers which accounts for 15% of sales.

KETEPA is the largest tea packing company in Africa belonging to tea growers grades, blends, and packs




some of the tea then sells to the local market and exports superior qualities.

Other companies which pack tea for local sale include Kikuyu Highland Tea Company and Unilever Kenya (Home Cup).



READ MORE

5 significance of coral coast to Kenya



Formed from tiny marine organisms called coral polyps

Coral polyps live in colonies.

They extract from sea water, calcium and use it to build protective shells

When they die their skeletons pile together and are commented together by calcareous algae to form a ridge like rock parallel to the shore called a coral reef.



Coral reefs include fringing reefs barrier reefs and a toll.

 Significance of coral coast to Kenya  

  • Rias have been used to develop habours
  • Most resultant land forms are tourists attractions sites
  • Some Rias are habitat for marine life which promotes fishing industry
  • Coral rock is a raw material for cement industry
  • Most of landforms have promoted education and research.




READ MORE