Welcome to Olympus Lookout!
This is a great spot to enjoy the sunrise over the Ocean and Cape Cleveland!
Despite being an official lookout and easily accessible via a very short walk (50 m) along an unsealed path, this location is not much known. Please be careful when standing on the lookout boulder, since the railing has been removed a while ago. There is parking space for one car at the trail head, but please make sure not to obstruct the driveways of the local properties.
While you are enjoying the vista, here is a little bit of geological history.
What we know nowadays as Magnetic Island was formed in the Permian Period about 280 - 250 million years ago. Within the earth’s crust, molten rocks and minerals pushed towards the surface, allowing them to cool and crystalize before ever being exposed to the environment. Once solidified, so called Intrusive Igneous Rocks were formed; a very common example of such rocks is Granite. Over time, much 'softer' rock layers overlying and surrounding the Granite were carried away (eroded) by waves, rain, wind, and storms. It remained the much harder Granite formations (6 to 7 on the Mohs scale of mineral hardness) that now dominate the landscape of Magnetic Island and which still document this erosion processes through their mostly rounded appearances. Embedded inside of the Granite are relatively large crystals that can be easily seen with the naked eye. They were created through the comparably slow cooling process allowing the crystals to ‘grow’. The colour of granite is determined by the composition of crystals and minerals it is composed of. Crystals of feldspar and quartz make up the majority of granite, giving it a creamy white colour. Where Potassium Feldspar (pink – red), Muscovite (yellow – gold), Biotite (brownish) or Amphibole (greenish) are abundant as well, the colour of the granite changes accordingly.
Dolerite is another form of Intrusive Igneous Rock, which is slightly softer than Granite (5 to 6 on the Mohs scale). It is formed by molten magma which is forcing its way into pre-existing cracks, gaps, and ruptures in the surrounding rocks. There, it can form so called dykes, which are generally narrow lines of Dolerite that follow a certain direction for meters or even kilometres. Dolerite is dark in colour since it is a mafic rock, meaning that it contains high concentrations of heavy minerals such as forms of iron. During its formation process Dolerite is cooling comparably quick, resulting in a very fine texture where the individual crystals cannot always be distinguished with the naked eye.
Well, now it’s your turn. To log this earthcache look out to the ocean from the posted coordinates. You will see a rocky outcrop with a distinct pattern to the left, which is leading into the water.
Q1. Describe the general pattern and colours of this outcrop, as well as potential differences in shapes.
Q2. Estimate how wide each section of this outcrop is.
Q3. Based on the information provided above, describe how the pattern, colours and shapes of this outcrop were probably created and why they might be different.
Q4. Include an image in your log taken from the outlook that includes yourself or a personal item, but please make sure NOT to include the outcrop!
Please send the Cache name (Olympus Sunrise) and GC-Code (GC9DREX) followed by the answers for questions 1 to 3 as chat message to me. Then, you can log this Earthcache straight away. I will get in touch if there is something wrong with any of the provided answers, or if no answers were provided at all. PLEASE NOTE: Every cacher must individually message me and provide all answers. "Team Answers" will not be accepted.