Examine the boulder at the listed coordinates and prepare your observations to the following earthscience tasks. Please provide your answers to the cache owner in a timely manner, i.e. less than a fortnight.
-Describe the shape and size of the boulder. Why do you think it is this shape?
-Can you see a xenolith? Shape and colour of the xenolith?
Now that’s erratic! Do you see the large boulder? Does it look different from the geology around it. Does it look out of place? Are you wondering where the boulder came from?
This boulder is called a “glacial erratic.” Once a part of a glacier moving across the landscape picking up rocks. When the glacier that held the boulder began to melt and recede from this area, the melting glacier left this rock behind. Today, the boulder serves as evidence that a glacier covered this area at one time. In Bathurst even boulders can be surprising.
A glacial erratic as a piece of rock that differs in size and type of rock native to the area in which it rests; the name "erratic" is based on the errant location of these boulders. These rocks were carried to their current locations by glacial ice, often over many kilometers. In this case the nearest granite is on Mt Panorama over 3km away. Erratics can range in size from pebbles to large boulders. What can you see here?
A xenolith is a rock fragment which becomes enveloped in a larger rock during the larger rock's solidfication and hardening. You will see a xenolith on the side of the large erratic boulder.