Reflections The perfectly still waters of Alexandra Cave in South Australia reflect the stalactites
ReflectionsThe perfectly still waters of Alexandra Cave in South Australia reflect the stalactites hanging tight to the ceiling above it that have precipitated drop by drop from water supersaturated in calcium carbonate. Part of the world heritage Naracoorte Caves in the limestone area in the south of the state, the park contains 26 caves of varying beauty and interest. Some of the cave contain world famous fossil deposits of extinct animals including Australian megafauna, mostly extinct since the arrival of humanity on the island continent.There are two layers of limestone here, interrupted by a gap of non deposition of nearly 180 million years, creating an unconformity in the rocks deduced from the fossils that they entomb. Most of the rock is 200 million years old, as the Triassic era ended and the world of the dinosaurs was taking shape. Groundwater during wet areas has carved out the caverns, which trapped the animals that were discovered fossilised within, preserved within layers of blown in topsoil up to 20 metres thick. The area also contains live fauna, including grey kangaroos, possums and wombats.LozImage credit: dmmaushttp://www.environment.sa.gov.au/naracoorte/Visit_Naracoorte_Caveshttp://www.environment.sa.gov.au/naracoorte/experience/Alexandra_Cavehttp://www.exploreaustralia.net.au/South-Australia/Limestone-Coast/Naracoorte-Caves-National-Park/Back-to-nature -- source link
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