Geological History of the Australian Alps
The geological history of the Australian Alps starts when the majority of vitamin E Australia was submerged underwater at round 800 million geezerhood ago. At this time there were large down payment layers that cover the sea floor. By around 450 million years ago, the populace began to move underneath the continental plate causing pick up and folding (Australian Alps National Parks, 2010, Geology and geomorphology of the alpine embellish para.6). Magma rose up through the layers at temperatures reaching up to 1000°C. The magma that reached the sea bed due to weakness in the crust cooled quickly and formed a layer of basalt to a higher place the sediments (see diagram 1). Other magma intrusions settled in between sediment layers as batholiths or even across them as dikes. sheepcote caused this array of layers to be pushed together to the extent that some expanses were posing vertically.
Diagram 1. Ocean floor layering
The other process at work is metamorphic transformation of the aqueous rocks. As the sedimentary base was exposed to the above mentioned extreme temperatures they harden and survive new rocks under the change in pressure in the environment. The type of new rock material that is formed depends on the extent of these changes.
Due to continual folding, many of these rocks were revealed to the surface. Examples found in Kosciusko National Park include slate and phyllite.
These processes continued until around 350 million years ago when the new layers were lifted outlying(prenominal) above the surface water and revealed to the elements. Weathering processes caused the mountains (caused by previous folding) to be reduced to plateaus and rolling hills. The weathering also caused the majority of the sediment formations in the low lying areas to further erode leaving butt joint the basalt formations as the more defining rock formations such as the basalt batholiths.
By around 2 million years ago, the area had been...If you want to get a full essay, order it on our website: Orderessay
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