Missoula Flood

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Missoula Flood Human beings existing, breathing, and walking around on a measureless, changing and growing quickly as times goes by. Similar to the human growth, landforms kept on changing rapidly over years after years. For many centuries, geologists believed landscapes were formed through a long process known as uniformitarian- a “gradually” slow process of changing its landscapes toward its environments. Evidence of multiple catastrophism- a “speed” process of landform has been developed over the years, especially during the time of J. Harlen Bretz, a remarkable geologist who defied the scientific belief of his day and argued that sudden flood of almost unbelievable force rather than the slow uniform process. By recognizing the effects of catastrophic flooding on the Columbia Plateau of eastern Washington, the Missoula flood was brought upon the geologist community. The event of Missoula flood caused spectacular changes in landscapes. Even though thousands years of land erosion, scars of the flood still visible and noticeable. This significant event made remarkable changes in the geology, and guide us to a new level of understanding the causes of changes in the past leading to present and into the future as well. Landscapes around us significantly change because of the Missoula flood. Bretz began to realized the area of Puget Sound- area filled with valleys and complex drainage channels and had been covered by mountain glaciers - is made up of giant discarded river channels during the time of glaciers expansion nudged the drainage system southward. (p. 19) One of the places that Bretz visited was Columbia River Gorge, a stretch of steep river valley that cuts its way through the Cascade Mountains. (p. 27) Here Bretz found certain number of misfit rocks called erratics, a rock type that located distance away from their area of origin. Erractics not only came from the coast but the interior of Washington and Idaho. Found their way into the Columbia Gorge, their boulders have clearly avoided the usual breaking up and smoothing down that occurs to river tumbled rocks. Rolling, grinding, and polishing action did not transport these erractics, something irregular has occurred. Their sizes are a thousand times larger than the river gravels and are likely to be angular rather than smooth. At the same time, Bretz notices the oddness of its dry falls in the Columbia Gorge on the U.S. Geological Survey map of Quincy Basin, showed up clearly at the western end of the basin.
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