The spectactular arrangements of boulders that make up the Devils Marbles are in fact, the result of breaking down rather than a building up of rocks.
The marbles are remnants from a solid mass of granite, the bulk of which still lies underneath them.
So how did the Devil get his Marbles.
Around (Question 1 below) million years ago, molten magna squeezed through ancient sandstones of the earth's crust and cooled into hard granite rock, the Devils Marbles Granite.
Shrinkage as the granite cooled and pressures within the earth caused right angled patterns of cracks called (Question 2 below) to form.
As the overlying rocks were eroded by wind and water, the granite came to be closer to the surface
Groundwater filtered down the (Question 2 below) and reacted with some of the minerals in the granite to form clays. This process called (Question 3 below), was helped by a warm, humid climate. Weathering was greatest at the corners of the blocks, where more surfaces were exposed.
Eventually, the overlying rocks were eroded away and the granite was exposed to the elements. The softer weathered granite around the edges of the blocks was washed away leaving boulders on top of one another and strewn across rock platfoms.
To log your find you will need to send me an email with a few answers to the questions below:
Question 1. How many million years ago was molten magna squeezed through the ancient sandstones?
Question 2. What are the right angled patterns of cracks called?
Question 3. What is the process where groundwater reacts the minerals in the granite to form clays?
In order to respect the wishes of the Traditional Aboriginal Owners of this area please do not upload pictures of Karlu Karlu National Park
All information can be obtained from the interpretive signs found at GZ.