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〕 | lat_d = 46 | lat_m = 50 | lat_s = 15 | lat_NS = N | long_d = 93 | long_m = 9 | long_s = 24 | long_EW = W | area_unit = acre | area_imperial = 15200 | area_round = -2 | established = 1961 | management_body = Minnesota Department of Natural Resources | map_locator = Minnesota | map = Minnesota Locator Map with US.PNG | map_caption = Location of Savanna Portage State Park in Minnesota }} Savanna Portage State Park is a state park of Minnesota, USA, established in 1961 to preserve the historic Savanna Portage, a difficult trail connecting the watersheds of the Mississippi River and Lake Superior. The park contains a drainage divide separating the West Savanna River, which drains to the Mississippi River and the Gulf of Mexico, from the East Savanna River, which flows in an opposite direction to the Saint Louis River, Lake Superior and the Great Lakes, and the Saint Lawrence River to the Atlantic Ocean. Savanna Portage was a canoe portage used by Native Americans for centuries before being used by European explorers, fur traders, Voyageurs, ''coureurs des bois'', and missionaries of the 18th and 19th centuries. It was a vital link connecting the Mississippi waterways to the west with the Great Lakes to the east. The portage was listed on the National Register of Historic Places in 1973 for having state-level significance in the themes of commerce, exploration/settlement, and transportation. The park which now contains it is located north and east of McGregor, Minnesota, and approximately west of Duluth. ==Geology and topography== The park is located on the divide between the watersheds of the Great Lakes and the Gulf of Mexico, both of which drain to the Atlantic Ocean. The area is a low-relief plain which was once a glacial lakebed. During the last phase of the Wisconsinan glaciation, the deteriorating continental glacier left behind connected lakes, known as Glacial Lakes Aitkin and Upham. Formed by the retreat of the Saint Louis Sublobe of the Superior Lobe of the glacier, Lake Upham drained through Lake Aitkin to the Mississippi River. The retreating glacier and the lakes deposited sand and sediments in the lakebed. As the lakes drained these sediments became the present plain. The plain at first was drained by the Cloquet River, which then ran west to the Mississippi River. By the process of stream piracy, the smaller Saint Louis River, which runs to Lake Superior, captured the Cloquet River and most of its drainage basin. This left behind the East Savanna River which drains into the Saint Louis River, Lake Superior, the lower Great Lakes, and the Saint Lawrence River, and to the west, the West Savanna River, which is tributary to the Mississippi River.〔〔〔 The old lake plain is part of the Tamarack Lowlands Subsection within the Northern Minnesota Drift Plains Section of the Laurentian Mixed Forest. Lacustrine sediments deposited by the glacial lake are parent to the present soils of peats, silt, and sand; the peats are in marshes which form large parts of the park. These wet lowlands adjoin rolling hills which are end moraines of the recent glaciation. These moraines are part of the Saint Louis Moraines Subdivision of the Northern Minnesota Drift Plain.〔(【引用サイトリンク】 publisher = Explore Minnesota Tourism )〕 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「Savanna Portage State Park」の詳細全文を読む スポンサード リンク
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