Mount Ommanney
In Western Australia, granite plays a significant role in the landscape and geological history. This EarthCache seeks to unravel the mysteries of this igneous rock formation and provide you with a deeper understanding of its origins and characteristics.
Granite is one of the most common rock types on the planet. It is a very hard rock, often with large crystals that formed slowly as the molten rock cooled over 2km below the earth's surface. Granite is an intrusive igneous rock formed deep within the Earth's crust. It consists mainly of three minerals: feldspar, quartz, and mica. The composition and texture of granite can vary, giving rise to a diverse range of patterns and colors. As you explore the suggested granite outcrop locations, take note of the various textures and colors present in the rock. Consider the geological forces and processes that shaped these formations over millions of years. Marvel at the intricate patterns and appreciate the beauty of nature's artwork.
Erosion is a significant geological process that can greatly influence the appearance and characteristics of granite rocks. The outcrops of Granite you can see on Mount Ommanney have been exposed to the elements. Over time, natural forces such as water and wind can wear away the surface of the granite, shaping the landscape and revealing unique features. Here are some key aspects related to erosion and its impact on granite rocks:
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Weathering: Weathering is the initial stage of erosion and refers to the breakdown of rocks into smaller fragments. Granite, although a durable rock, is not entirely immune to weathering. Physical weathering processes like freeze-thaw cycles, thermal expansion, and mechanical abrasion can contribute to the gradual disintegration of the granite surface.
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Water Erosion: Water is a powerful agent of erosion. In Northam, rainfall, streams, and rivers play a crucial role in shaping the granite landscape. Over time, flowing water can carve channels into the granite, exposing unique formations and creating distinct landforms. Look for evidence of water erosion, such as rounded or polished surfaces, deep channels, or potholes in the granite.
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Wind Erosion: Wind erosion, although typically less significant than water erosion in shaping granite features, can still have an impact. Wind-blown sand and dust particles can act as abrasive agents, slowly wearing away the exposed surfaces of the granite rocks.
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Chemical Weathering: Chemical processes can also contribute to the erosion of granite. Acidic rainfall or chemical reactions with water can lead to the breakdown of certain minerals within the granite, altering its composition and weakening its structure over time.
Please email me the answers to the following questions:
1. What kind of rock form is Granite? (Igneous/Sedimentary/Metamorphic)
2. Look closely at the surface. Describe any examples of erosion by wind, temperature, or water you can see.
3. From the list of erosion types above, which ones do you think have had the greatest effect on the rocks here?
4. Take a photo of yourself of the view to add to your found log.
What to do now:
In accordance with the guidelines, the procedure for logging an Earthcache is:
- Send me the answers.
- Log your visit. "People do not need to wait for permission to log your EarthCache."
Please note: If answers have not been received within 10 days, you will risk having your found log removed.