Shall I stay put in Alice for the day, or shall I go explore? I had crossed a lot of nothing the day before, so the temptation to sleep late and just bum around the town was strong, but at the end I decided to take an organized tour to the West MacDonald Range. The city of Alice Springs seats on the remnants of a mighty Permian mountain belt, maybe in the same way Knoxville seats on the axis of the Appalachian Mountains. So after crossing a couple of thousand kilometers of bush, the eye sees an east-west range of hills, the MacDonald Range, that cuts the desert in half. Alice Springs was located here, on a gap between the hills, as the main telegraph station between Adelaide on the south and Darwin on the north. The lead of the topographic party laying the telegraph line was Stuart, Alice was his wife, and he named the station after her (who alas never saw the town because she didn't fancy traveling for weeks on the desert) with the added emphasis on the "springs", which are water holes that form where streams carrying groundwater in their sandy channels are forced to surface when they find the hard obstruction of the rocks of the range.
Imagine a hard ledge of quartz sandstone, folded into a very long anticline that was later eroded, leaving behind a long ridge topped by the quartz sandstone, here and there cut by streams that can turn into a torrent during a flash thunderstorm, but which are otherwise dry, except at the very foot of the gap where the water hole forms. The sandstone ledge is orange in color and goes on for kilometers, so it is a very visible regional marker. There are a few faults here and there, and the sandstone repeats itself on every limb of the different folds, making the landscape rather unique.
When seen from a distance, the segments of the sandstone ledge look like fat caterpillars, marching one after the other from east to west. This has given rise to one of the aboriginal tales of the Dream Time, when Earth, plants, animals, and people were formed. This area was the realm of the beetles, when all of a sudden the caterpillars showed up at the border. Instead of making a traditional fire at the demarcation line to wait for the beetles to come greet them, so they could ask for permission to come into their land, the caterpillars shamelessly tramped in, eating all the grass and leaves they found on their path. The beetles then fought the caterpillars and chopped off their heads forming the water gaps. The moral of the story is that before trespassing into someone else's land one must first ask for permission.
Each one of the gaps we visited were awe-inspiring, with the big cliffs of reddish rock rising tens of meters above the level of the gap, and all around a veritable natural garden of cycads and trees that are in stark contrast with the shrubs and spiny spinifex grasses of the surrounding dry lands.
Some of the rocks are Proterozoic (2.2 billion to 600 million years ago) and have been metamorphosed to quartzites and gneisses, and these are covered by Paleozoic quartz sandstones, limestones and dolostones, and variegated slitstones and shales (which do much to enhance the artistic value of the scenery). The whole section was then deformed in the late Paleozoic, in what Aussie geologists call the Alice Springs orogeny. The famous Uluru rock is formed by the same type of red sandstones, which were tilted vertically during the same orogeny (I am skipping a visit to Uluru for the simple reason that it is 500 km away!).
Here is another fable from aboriginal lore: Since time immemorial aboriginal hunters have always targeted the last emu. That is, they lay in ambush by the water hole, look at all the emus come, drink, and then leave, and then they hunt the very last emu. The reason is that in this way the emus do not associate the water hole with danger. Two days later someone notices something is amiss and they ask each other "Where is Kevin?" But nobody remembers that the last time they saw Kevin was at the water hole, so they eventually go back. The moral of the story is that you do not want to be the last emu.
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