sedimentary rocks
sedimentary rocks are formed by material derived from breakdown of pre existing rocks and other organic materials
these type of rocks are normally formed near the earths surface
there are 2 types of sedimentary rocks, ^^organic^^ and ^^inorganic^^
organic are created from once living organisms
inorganic are formed by the weathering and erosion of older rocks
all sedimentary rocks have the common characteristic of layering or stratification. these layers are known as strata
the lines separating these layers is called the ^^bedding plane^^
the vertical cracks joining the bedding planes together are known as ^^joints^^
sediments are converted into rock by ^^compaction and cementation^^
compaction is when particles are pushed and squeezed together under the weight of the overlying sediments
cementation is when the cementing agents bind particles into a solid rock
these combined processes are called ^^lithification^^
limestone is an organically formed rock
it is the most common rock in ireland
it forms a landscape known as a karst landscape and this can be found in the burren in county clare
irish limestone was formed in warm, shallow, tropical seas about 300-350 million years ago
ireland was close to the equator during this period called the carboniferous period and its called carboniferous limestone
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