Educational Info - Simple This EarthCache will take you to the summit of Mt Tinbeerwah, a 265m high mountain which is a volcanic plug remaining from volcanic activity millions of years ago, situated a few kilometres to the west of Noosa in Queensland. This entire area, stretching from the New South Wales boundary in the south [Mt Warning] and as far as Murgon in the north, with Toowoomba and Dalby on the western side, is all part of the greater Moreton Clarence Basin geological area. The main feature that we are concerned with in this EarthCache comes from the Cainozoic [Tertiary Miocene] Period – which is relatively young [65 to 2 million years] in geological terms. The composition of the rocks that you will find in these areas are rhyolite, basalt, agglomerate and trachyte.
The mountain is a volcanic intrusion into the surrounding Myrtle Creek Sandstone which consists of sandstone, shales, siltstone, conglomerates and coal. Over the years the surrounding area of softer rock was eroded away and the mountain was left as it was of a much harder igneous rocks.
At the given co-ordinates you will find a 360 degree lookout which will provide magnificent views of the surrounding Sunshine Coast and Cooloola areas. The walk is approximately 1km and you need to allow at least 45 minutes for it.
In order to log the EarthCache you will need to answer the following questions via an e-mail to the developer, cincolcc(at)gmail.com
1. At the given co-ordinates [summit lookout] you will need to take two compass bearings – 275 degrees and 240 degrees. I would suggest standing in the lookout in order to do this exercise. Describe the 2 features that you will see at these bearings.
2. Look at the surrounding rock. What is the predominant underlying colour of the rock?
3. This colour is very distinct and will help you identify what rock it is. What type of rock do you think it is [rhyolite, basalt or trachyte] and explain how you came to this conclusion?
4. At S 26° 23.360 E152° 58.447 you will find a particular geological feature. Describe what it is that you see and how you think it might have been formed.
FTF goes to = Just a Trifle
{Information in this description was retrieved mainly from the Geological Survey of Queensland Map – 1 : 500,000 [Moreton Geology] by R.J. Allan, Chief Government Geologist.}
