The Process of Rocks Formation - the Basis of Our Earth
A rock may be something you just kick out of your way or throw into the water, but you never know how old that rock could be or where it came from. A rock is a solid naturally occurring mass/lump of consolidates mineral matter that makes up the earth’s crust and its interior. Overtime rocks have changed from one rock to another with weathering, erosion, pressure and heat etc. This is in a process called the rock cycle and the essay about rocks examines this process and shows what type of rocks can be and how they creates.
Rocks are sorted into 3 basic groups depending on how they are made. These three main groups are sedimentary, metamorphic and igneous rocks. Sedimentary rocks are formed by a weathering process; either by compaction and cementation of mineral rock fragments or the precipitation of dissolved mineral. Metamorphic rocks are made from existing rocks that are put under an intense amount of heat and pressure. Igneous rocks are formed when molten rock (magma) that is at or below the earth’s surface cools and crystallizes. Finally, when any rock is weathered or eroded, they turn into small rock sediments.
Igneous rock can be sorted into 2 categories; intrusive and extrusive. Intrusive rocks are formed when the magma cools slowly beneath the earth’s surface and hardens into igneous rocks. Gabbro and granite are some examples of intrusive igneous rock. Extrusive rocks are formed when the magma comes to the earth’s surface due to a volcanic eruption. This magma cools faster to from fine grained igneous rocks. Some examples of extrusive igneous rock are pumice, basalt and obsidian.
As we all know the indigenous people own the land, we stand on today and the land that wave rock lays on. This is home to the Njaki Njaki nyoonar people. These peoples traditional land covers from Lake Kind in the south, to the Kulin in the west, Nungarin in the north and to the land east if Hyden and Narembeen. The many granite outcrops, waterways, land formations and flora and fauna within the region hold much cultural significance to the Traditional Owners through a continued relationship that spans over thousands of years. There is no dreamtime story connected to the wave rock because the aboriginal people are believed to have avoided the rock.
The Wave Rock located in Hyden Western Australia is one of Australia’s most recognisable landform. The rock is a 15m high granite cliff and it is 110m long. The cliff looks like a giant multi-coloured granite wave about to crash. It is a grey, red, ochre and sandy striped wave. The rock is made up of granite which means it’s an intrusive igneous rock. Pyrophytic granite is the type of granite found within the wave rock. This granite is usually red or white and contains black spots. The crystals in the rock are among the oldest in australia as in 1960, crystals from Hyden rock were dated as being 2700 million years old.
So how did the amazing landform come to be. Like most great things it took time. A lot of time. In a nutshell the rock was originally buried by soil and as this was slowly eroded and the granite cliff was exposed. However, the amazing colour detail was created whilst the rock was still buried. When the rainwater ran down the sides and into the moist soil around the rock humic acid dissolved into the rock. Slowly the soil was eroded, and the wave rock was exposed. The water from the springs running down the rock during wetter months also dissolved minerals adding to the colouring of the waves. The rain cut the base of the rock and that is what caused the curve shape.
Aboriginals people have been using rocks since day dot however two main types of rocks used was ochres and grinding stones. Ochre which is found in the wave rock is used by aboriginal people in all different colours for decorating implements, for body are and it still used today for ceremonies. The most widely used ochres is red ochres which was used extensively on the body. In Central Australia, there were three kinds of ochre used in the main. They were yellow ochre, white ochre – or white pipe clay – and red ochre. In some particular mines in Central Australia, the ochre has a mica component, and when it’s placed on the body, particularly on the face, it gives off quite a shiny look. To process foods grinding stones were used. Fine seeds were put on a stone with a divot in it and a top stone was used to grind the seeds to make flour.
In conclusion without rocks we wouldn’t be standing on this Earth. Rocks have helped the aboriginal people live their lives and are also the basis for some of the most beautiful landforms in the world.
