Chemical Weathering - Surface Limestone Pavement Flashcards
What is limestone pavement
Large flat area of exposed limestone rock that has its soil cover removed by probably soil or glacial erosion
What process causes limestone pavement
Chemical erosion - carbonation
What is a karst landscape
And area of bare limestone rock
Example of limestone pavement
Burren co Claire
Why does carbonation occur
> as rainwater falls through atmosphere it absorbs carbon dioxide to form a weak carbonic acid
as this carbonic acid seeps through soil is abroad humid acids from dead plant and animals
this reacts with the calcium carbonate in sedimentary rocks to form calcium bicarbonate which is soluble and washes away with rain water
Why is sedimentary rock weathered so easily
> Sedimentary rock is made up of grains bonded together by cementing agents such as calcite and silica
these cementing agents are easily chemically weathered
Name 2 minerals that are resistant to chemical weathering
Quartz and mica
What does pervious limestone mean
Water passes down through joints and bedding planes rather than the actual rock it self
Quick summary of the limestone rock
It is a grey organic sedimentary rock made of calcium carbonate it has verticle joints and horizontal bedding planes between each strata
How are joints widened and what do they form into to
> carbonation concentrates on the joints and bedding plants
Joints are widened and deepened becoming long deep grikes
rock between grikes are called clints
What does the combination of grikes and clints form
Limestone pavement
What happens to the top soil when it has washed away
It seeps into grikes and plants grow in them
What are karrens
As the surface of the clints dissolve small hallows in the clints form
What may form on the clints
Karrens - small hallows
What is fluting
Fluting is when water runs down the side of clints dissolving it and forming furrows along the edges
