geography (chemical weathering)
explain the term karst landscape
-is is a limestone landscape. -the soil cover has been removed and the limestone is exposed to weather
how are karst landscape landscape formed?
-it is formed by the effects of carbonation
how are stalagmites formed?
-when drops of water fall on the ground,of a cavern,and evaporates,it leaves behind bits of calcite -these deposits build up to form a cone shape,called a stalagmite
describe carbonation
-when rain passes through the atmosphere,it picks up some carbon dioxide -the carbon dioxide mixes with the rainwater,making a weak carbonic acid -when the weak acid rain hits limestone,it slowly dissolves the limestone
how is a swallow hole formed?
-when rivers flow onto bare limestone,the water begins to dissolve the limestone by carbonation -soon the water goes underground and disappears from the surface -the passage where the river goes underground is called a swallow hole
how are stalactites formed?
-when the water containing dissolved limestone seeps through the limestone,it hangs from the ceiling of the cavern for a while -some of the water evaporates,leaving behind bits of calcite attached to the roof -these deposits build up to form an icicle like shape hanging from the ceiling of the cavern
how are caves formed?
as the river goes underground,the water dissolves everything in its path,cutting out long tunnels called caves
give one example of chemical weathering
carbonation
explain the term permeable
if something is permeable,water can easily penetrate it
explain the term limestone pavement
it is a large area of exposed limestone
explain the term cavern
it is an enlarged cave
explain the term swallow hole
it is the passage where a river disappears underground of a limestone pavement
what is chemical weathering?
it occurs when rocks decay or dissolve because of a chemical change
explain the term karst
karst is another name for limestone
how are pillars formed?
over time,the stalagmites and stalactites grow and join up to form a pillar
how are caverns formed?
sometimes,the cave is enlarged to form a large chamber,called a cavers
explain the term bedding plane
the line in rocks that separates 2 layers
explain the term clints
the parts of limestone,left alone after the process of carbonation are called clints
explain the term joints
the vertical cracks in limestone
explain the term cave
they are long underground tunnels
explain the term grikes
they are the cracks in limestone widened and deepened after the process of carbonation
