Glacial crevasses

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Where debris had been concentrated in glacial crevasses, melting ice left hillocks, monticles, hummocks, knolls, braes-collections of lumpy hills known generically to the Scots as kames. In Indiana as in Scotland-in La Bresse and Estonia as in New England and Quebec-the sort of country left behind after all these features have been created is known as kame-and-kettle topography. The interstate was waltzing with the glacier-now on the outwash plain, now on moraine, among the kettles and kames of Scottish Indiana. Roadcuts were green with vetch covering glacial till. We left 80 for a time, the closer to inspect the rough country. The glacier had been away from Indiana some twelve thousand years. There were many beds of  flexplek huren arnhem dried-up lakes, filled with forest. In the Boundary Waters Area of northern Minnesota, the ice went back ten thousand years ago, possibly less, and most of the lakes it left behind are still there. The Boundary Waters Area is the scene of a contemporary conservation battle over the use and fate of the lakes. “Another five thousand years and there won’t be much to fight about,” Anita said, with a shrug and a smile. “Most of those Minnesota lakes will probably be as dry as these in Indiana.” Some of the larger and deeper ones endure. We made our way around the shores of Lake James, Bingham Lake, Lake of the Woods, Loon Lake. Like Walden Pond, in Massachusetts, they were kettles. The woods around them were bestrewn with boulders, each an alien, a few quite large. If a boulder rests above bedrock of another type, it has obviously been carried some distance and is known as an erratic. In Alaska, I have come upon glacial erratics as big as office buildings, with soil developing on their tops and trees growing out of them like hair. In Pokagon State Park, Indiana, handsome buildings looked out on Lake James-fieldstone structures, red and gray, made of Canadian rocks. The red jasper conglomerates were from the north shore of Lake Huron. The banded gray gneisses were from central Ontario. The sources of flexplek huren den haag smaller items brought to Indiana by the ice sheets have been less easy to trace-for example, diamonds and gold. During the Great Depression, one way to survive in Indiana was to become a pick-and-shovel miner and earn as much as five dollars a day panning gold from glacial drift-as all glacial deposits, sorted and unsorted, are collectively called. There were no nuggets, nothing much heavier than a quarter of an ounce. But the drift could be fairly rich in fine gold.

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