Flipkart

Tuesday 20 January 2015

Geography

                              Major Land Forms
  • The landscape is being continuously worn away by two processes weathering and erosion.
  • Weathering is the breaking up of the rocks on the earth's surface.
  • Erosion is the wearing away of the landscape by different agents like water, wind and ice.
  • The eroded material is carried away or transported by water, wind etc., and eventually deposited.
  • This process of erosion and deposition create different landforms on the surface of the earth.

                                Work of River

  • The running water in the river erodes the landscape.
  • When the river tumbles at steep angle over very hard rocks or down a steep valley side it forms a waterfall.

                                     
                                   
What is meanders?
  • As the river enters the plain it twists and turns forming large bends known as meanders.
  • Due to Continuous erosion and deposition along the sides of the meander, the ends of the meander loop come closer and closer.
What is ox-bow lake?
In due course of time the meander loop cuts off from the river and forms a cut-off lake, also called an ox-bow lake.

What is Flood plain?
As it's floods;it deposits layers of fine soil and other material called sediments along its bank. This leads to the formation of a flat fertile flood plain

What is levees?
The raised banks are called levees.

                               

What is Distributaries?
As the river approaches the sea, the speed of the flowing water decreases and the river begins to break up into a number of streams called distributaries. 
What is Delta?
Each distributary forms its own mouth the collection of sediments from all the mouths froms a delta.
                                    

                         Work of Sea Waves

What is Sea caves?
The erosion and depositions of the sea waves gives rise to coastal landforms. Seawaves continuously strike at the rocks. Cracks develop.Over time they became large and wider.Thus hollow like caves are formed on the rocks.they are called Sea caves.
                              

What is Sea Arch?
As these cavities become bigger and bigger, only the roof of the caves remains thus forming sea arches.


What is Stack?

Further, erosion breaks the roof and only wall are left.These wall like features are called stacks.


What is Sea cliff?
The steep rocky coast rising almost vertically above sea water is called sea cliff.



                                  Work of Ice
  • Glaciers are rivers of Ice which too erode the landscape by bulldozing soil and stones to expose the solid rock below.
  • Glaciers carve out deep hollows.

What is Glacier Moraines?
The material carried by the glacier such as rocks big and small,sand and silt gets deposited.These deposits form glacial moraines.





                       Work of Wind

An active agent of erosion and deposition in deserts is wind.

What is Mushroom rock?

In deserts. you can see rocks in the shape of a mushroom commonly called mushroom rocks.                                         Wind erode the lower section of the rock more than the upper
part. Therefore, such rocks have narrower base and wider
top.


What is Sand dunes?

When the wind blows, it lifts and transports sand from one place to another.when Stops blowing the sand falls and gets deposited in low hill like structures.These are called sand dunes.


What is loess?

When such sand is deposited in large areas, it is called loess.

No comments:

Post a Comment