Harriet Reece, Lewiston and Cavendish, is the winner!
Glaciers is the answer for Week 477 of Orofino History Trivia a special feature to celebrate the history and heritage of Clearwater Country.
Join in the discovery!
Tuesday: Slow, but with noticeable results
Wednesday: Kelly Creek
Thursday: Rocks and mud
Friday: Usually on the north and east side of a mountain or high ridge
Saturday: Wore down some places and made others jagged
Monday: Left evidence
Clearwater country had numerous glaciers, according to Ralph Space in his book, The Clearwater Story: A History of the Clearwater National Forest, They usually formed on the north and east side of a mountain or high ridge. That was due to the snow melting less on the north side and because the winds generally blow northeast. Much snow which fell on the ridges drifted to the valleys of the northeast. Some of the glaciers first started moving in a northerly direction, but the valley turned south. These glaciers, through their slow grinding and pushing, produced results which are still noticeable.
There a number of lakes, ranging in size from ponds to lakes about a mile long in the high country. These lakes were all formed by glaciers. Space said he had never seen a lake on the Clearwater not formed by a glacier, but, he added there were a few lakes he did not visit.
Traveling up stream which arises in the high country, a visitor's first sight of glacial action is a terminal moraine, a ridge of rocks, gravel and mud left by the glacier when its leading edge melted and receded. The moraines are often easily picked out, but sometimes water action removed much of the moraine and left only portions noticeable on either side of a valley. Above the moraine the valley is usually U-shaped from the grinding and scraping action of the glacier, Space said.
Occasionally, the glaciers did some unusual and interesting things. For instance Kelly Creek was formed y the joining of the North and South forks of Kelly Creek. Glaciers came down both of these valleys. They joined and moved on down to below the mouth of Bear Creek. When they melted back the one in the North Fork, because it was in lower country and more exposed to the sun, melted first. The water coming out of the North Fork formed a pond back of the glacier, Space says. That built up until it ran over a low ridge and came back to Kelly Creek below its original mouth. When the glacier in the South Fork melted back to above the channel of the North Fork, it left so much mud, rock, etc. in the mouth of the North Fork that it never returned to its original channel. The trail up the North Fork goes up through the old channel because the new one is still quite steep and rocky.
Although glacial action was mainly confined to the higher portions of the Clearwater, the water from the melting glaciers had marked effects on the rivers below. The increased flows caused the rivers to cut deeper into the earth. That is the reason the Clearwater and its branches have steeper side walls near their bottoms than on the high banks. The banks before the glaciers formed a flat V or a U, but the water action changed them to a broken V. After the glaciers the lower part of the broken V began to fill and is still filling because there is not enough water to remove the material that washes and rolls in from above.
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