Uluru and scientific illiteracy

I cannot begin to imagine what the first people who saw Uluru thought about it, nor can I remember reading what the first Europeans to see it thought. I have never actually seen it myself (I only got as far as Mount Conner, which is impressive itself), but living in Alice Springs for a while made me feel like I had seen Uluru, as it is plastered everywhere you look; a by-product of the tourist trade, I suppose.

Geologists know that Uluru is composed of arkose, a rock type like sandstone, but with a greater proportion of the mineral feldspar (as opposed to quartz) among its grains. This is a fairly unusual type of rock as far as sediments go, because feldspars weather and decay (to clay mostly) much, much faster than does quartz. This indicates that the arkose forming Uluru, was laid down relatively quickly. It was deposited in the Early Cambrian (about 540 million years ago) and the source of the sediment was from the uplifting of the Peterman Ranges, some distance to the South. Appropriately, this uplift event is called the Peterman Ranges Orogeny. As a sediment, the arkose was laid down with the bedding planes at or close to horizontal, but they have been tilted by significant folding and faulting of the crust, so that now the bedding planes are almost vertical. This faulting and folding event is termed the Alice Springs Orogeny and it occurred some 200 million years later, about 350 million years ago¹.

The preceding paragraph is a very brief explanation of what geologists know about the formation of Uluru. However, when in Alice Springs, a colleague told me that a bus driver had told his busload of tourists that Uluru was a large meteorite that happened to plonk itself in the middle of the desert. Unfortunately, we never found out who the driver’s company was, so we were unable to at least attempt to set them straight. I say attempt, because people are not always amenable to being put in touch with reality².

Some years later I bumped into a tourist who had been to Uluru and wondered how it got there. His explanation that he had formulated was that Uluru was a fossil termite mound. This was not as silly as it sounds because he had come to this conclusion after seeing ‘the brain’ on the side of the rock. That formation on Uluru does look like an excavated tunnel system, not too different to parts of some weathered termite mounds you see over central Australia (there is a whopper, at least 4 metres high and 3 metres in diameter on the Plenty River Highway). This tourist assumed that like many dinosaurs, termites were much larger in the distant past. After explaining to him what we do know about the formation of the rock, its age and the evolution of animals (termites weren’t around in the Cambrian, having evolved some 300+ million years later³), he apparently went away happy with having learnt something. It makes you feel good when someone thanks you for informing them.

Although his formulation may sound silly, he was actually using a method approaching that of science to come to a conclusion. He didn’t know much and his evidence was limited but he used his own observations to interpret what he was seeing. He, however, was not wilfully ignorant like so many who deny the understanding provided by science. When he realised that a geologist had more evidence and therefore greater knowledge of Uluru’s origins, he jettisoned his theory and embraced the modern geological understanding. That is in a nutshell, how science works. If evidence is available that shows a theory is incompatible with that evidence, you dump it and formulate a new one. The understanding we have doesn’t make Uluru any less of a marvel. Indeed, its history adds to its wondrousness.

Sources

1. https://parksaustralia.gov.au/uluru/pub/fs-geology.pdf
2. http://www.blotreport.com/australian-politics/first-brush-denialism/
3. https://en.wikipedia.org/wiki/Termite