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Silverton is a city in Marion County, Oregon, United States. The city is situated along the 45th parallel about northeast of Salem, in the eastern margins of the broad alluvial plain of the Willamette Valley. The city is named after Silver Creek, which flows through the town from Silver Falls into the Pudding River, and thence into the Willamette River. Silverton was originally called Milford, then Silver Creek; on July 16, 1855, Silver Creek became Silverton. Human habitation of the Silverton area extends back approximately 6,000 years before the present. In historical times, the region was dominated by the Kalapuya and Molala peoples, whose seasonal burns of the area made it plow-ready and attractive to early 19th century Euro-American settlers. Farming was Silverton's first major industry, and has been a dominant land-use activity in and around Silverton since the mid-19th century. Silverton is part of the Salem Metropolitan Statistical Area, and the population core of the Silver Falls School District. The population was 9,222 at the time of the 2010 census. ==Geography== Silverton is situated on the eastern edge of the Willamette Valley, a fertile and alluvial plain which stretches from the western foothills of the Cascade Range on the east, known as the Waldo Hills, to the eastern foothills of the Oregon Coast Range on the west. Silverton lies on either side of Silver Creek, a tributary of the Pudding River, which joins the Molalla River before emptying into the northward-flowing Willamette River. Abiqua Creek also empties into the Pudding River; it flows across the eastern valley north of Silverton, further draining the land around the city. Silverton's elevation is between above mean sea level with the steep-sided, heavily-wooded Waldo Hills to the south rising an additional . The agricultural richness of the environs is due to massive and repeated floods from prehistoric Lake Missoula in western Montana. Beginning approximately 13,000 years before the present, repeated flooding from Lake Missoula scoured eastern Washington and Oregon, carved out the Columbia River Gorge, and periodically swept down the Columbia River; when floodwaters met ice jams in southwest Washington, the backed-up water spilled over and filled the entire Willamette Valley to a depth of above current sea level,〔John Elliott Allen, Marjorie Burns, Sam C. Sargent, ''Cataclysms on the Columbia: A Layman's Guide to the Features Produced by the Catastrophic Bretz Flood in the Pacific Northwest'', Timber Press (Portland, OR 1986), ASIN B003XPEPX2, pp 175–189〕 creating a body of water known as Lake Allison. The gradual receding of Lake Allison's waters left layered sedimentary volcanic and glacial soils to a height of about above current sea level throughout the Tualatin, Yamhill and Willamette Valleys. Until the mid-19th century, the Silverton area was a broad, open grassland with small stands of Oregon white oak, ponderosa pine and Douglas fir. Stands of Oregon white oak, red alder, big leaf maple, and black cottonwood lined streams and river banks. While these tree species are extant today, widespread farming in the Willamette Valley between 1850 and 1870 altered the land through the discontinuation of widespread seasonal burning in the valley plains previously employed by the Kalapuya people. Large stands of Douglas fir and western red cedar, mixed with Oregon white oak, remain in the Silverton area, especially on eastern ridge tops and on the slopes of the Waldo Hills to the south. Due to decades of intensive timber extraction, mature second- and third-growth trees comprise existing evergreen stands. According to the United States Census Bureau, the city has a total area of , of which is land and is water.〔(【引用サイトリンク】url=http://www.census.gov/geo/www/gazetteer/files/Gaz_places_national.txt )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silverton, Oregon」の詳細全文を読む スポンサード リンク
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