Yesterday, I got back from a trip to the Margaret River region. What a place! No wonder it is such an expensive place to live… Wine, coffee, cattle, sheep, surfing and caves.
In the morning, my dad and I climbed through Mammoth Cave. In spite of the name, it is not the largest cave in area. This was a self-guided tour and we were given a device that could describe certain areas of the cave and provided some background geological information. The cave exit is through a doline – a sinkhole. I took a longer walk back to our car on the Marri Trail so I could appreciate more of the Australian flora in the region.
I followed Mammoth Cave with a climb into Lake Cave. Dad did not come along on this on account of all the stairs down into another doline; his legs were not up to it. This was a guided tour and a much smaller cave. The “lake” inside it is actually the stream that carved the cave out of the limestone, it is probably about 3 feet at its deepest. The suspended table formation was quite interesting.
It consists of two columns of calcite that are now supporting a flat “tabletop” above the surface of the water. Of course, this tabletop used to be on the floor of the cave, but the water has eroded that away over time. It is estimated to weigh about 6 tons.
Lake Cave also reveals the damage that humans can do to a cave system. Policy now commands no touching of any kind. In the picture to the left, you can see stalagmites that have become a dirty brown colour. New calcite deposits from dripping water have formed a clean white “frosting” over the top.
The brown discolouration comes from the oils and acids present in human skin. The part of Lake Cave where this was taken used to be beyond the tour catwalk; so people had to grab on to the rock to get further inside. Today, the catwalk has been extended all the way in to the deepest end – about sixty feet further than the suspended table.
The biggest cave in the Margaret River region is Jewel Cave. However, we did not explore this. Instead, we drove down to Augusta and Cape Leeuwin to tour the lighthouse there. I’m very glad to have seen this lighthouse! The calcified waterwheel is close to the lighthouse (it pumped water to the construction site for mixing with mortar) and is quite an interesting thing to see.
One aspect of this vacation that I never suspected would be seeing the Southern Ocean and the most southwestern portion of Australia. That is exactly what Cape Leeuwin is.
The international community commonly states that the Southern Ocean begins at 60 degrees latitude. This has yet to be ratified, so Australia puts forward the claim that the ocean is immediately south of the continent. As such, Cape Leeuwin is where the Indian Ocean and the Southern Ocean meet.
And the wind here! Unbelievable! Gale forces are common. Despite the stones of the lighthouse being 2 meters thick at the base and 1 meter thick at the top, the structure can still sway 1 centimeter.
After spending the night in Margaret River, we stopped in Bunbury. We visited Bunbury five years ago when I was last in West Australia. I took more photos this time, including some excellent shots of waves crashing on some basalt rocks. I also have pictures that will form a panorama from the top of Bunbury Tower; however, it will need to wait until I get home to process and upload it.