Wherever the bedrock is visible on the coastline of Victoria you will see these large grooves gouged out of the rock. They were made by glaciers grinding across the rock as they flowed down to the ocean, about 15,000 years ago. I read up a little on ice ages today because it suddenly occurred to me that the planet has had great periods of temperature fluctuations in the past. There have been about a half dozen ice ages in the last couple of million years, times when it got very cold and much of the world was covered with ice and then it warmed up again, all without the benefit of our pollution. The scientists' best guess at this time is that these global temperature fluctuations were caused by cyclical wobbles in the earth's spin and orbit, possibly in conjunction with changes in the ocean currents due to the shifting of the continents. Apparently we are still in an ice age since the defining characteristic is that there are areas that are permanently covered with ice, though these are rapidly receding.
Amazing landscape.
ReplyDeleteIt was formations just like these that led Horace de Saussure to realise the extent of past glaciations in his native Switzerland. It was the beginning of our understanding of the Ice Ages and glaciation.
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