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Minnesota is the most northern state outside of Alaska; its isolated Northwest Angle in Lake of the Woods is the only part of the 48 contiguous states lying north of the 49th parallel. Minnesota is in the U.S. region known as the Upper Midwest. The state shares a Lake Superior water border with Michigan and Wisconsin on the northeast; the remainder of the eastern border is with Wisconsin. Iowa is to the south, North Dakota and South Dakota are west, and the Canadian provinces of Ontario and Manitoba are north. With , or approximately 2.26 % of the United States,〔 (【引用サイトリンク】 publisher=infoplease.com )〕 Minnesota is the 12th largest state. ==Geology and terrain== (詳細はgneisses some 3.6 billion years old, or 80% as old as the planet. About 2.7 billion years ago, basaltic lava poured out of cracks in the floor of the primordial ocean; the remains of this volcanic rock formed the Canadian Shield in northeast Minnesota.〔 The roots of these volcanic mountains and the action of Precambrian seas formed the Iron Range of northern Minnesota. Following a period of volcanism 1.1 billion years ago, Minnesota's geological activity has been more subdued, with no volcanism or mountain formation, but with repeated incursions of the sea which left behind multiple strata of sedimentary rock.〔 In more recent times, massive ice sheets at least one kilometer thick ravaged the landscape of the state and sculpted its current terrain.〔 The Wisconsin glaciation left 12,000 years ago.〔 These glaciers covered all of Minnesota except the far southeast, an area characterized by steep hills and streams that cut into the bedrock. This area is known as the Driftless Zone for its absence of glacial drift.〔(【引用サイトリンク】 publisher=Minnesota DNR )〕 Much of the remainder of the state outside of the northeast has 50 feet (15 m) or more of glacial till left behind as the last glaciers retreated. 13,000 years ago gigantic Lake Agassiz formed in the northwest; the lake's outflow, the glacial River Warren, carved the valley of the Minnesota River, and its bottom created the fertile lands of the Red River valley.〔 Minnesota is geologically quiet today; it experiences earthquakes infrequently, and most of them are minor.〔(【引用サイトリンク】 publisher=University of Minnesota, Morris )〕 The state's high point is Eagle Mountain at 2,301 feet (701 m), which is only 13 miles (20.9 km) away from the low of 602 feet (183 m) at the shore of Lake Superior.〔〔(【引用サイトリンク】 publisher=geology.com )〕 Notwithstanding dramatic local differences in elevation, much of the state is a gently rolling peneplain.〔 Two continental divides meet in the northeastern part of Minnesota in rural Hibbing, forming a triple watershed. Precipitation can follow the Mississippi River south to the Gulf of Mexico, the St. Lawrence Seaway east to the Atlantic Ocean, or the Hudson Bay watershed to the Arctic Ocean.〔(【引用サイトリンク】 publisher=National Atlas )〕 The state's nickname, ''The Land of 10,000 Lakes,'' is no exaggeration; there are 11,842 lakes over 10 acres in size. The Minnesota portion of Lake Superior is the largest at and deepest (at , 393 m) body of water in the state.〔 Minnesota has 6,564 natural rivers and streams that cumulatively flow for 69,000 miles (111,000 km).〔 The Mississippi River begins its journey from its headwaters at Lake Itasca and crosses the Iowa border downstream.〔 It is joined by the Minnesota River at Fort Snelling, by the St. Croix River near Hastings, by the Chippewa River at Wabasha, and by many smaller streams. The Red River, in the bed of glacial Lake Agassiz, drains the northwest part of the state northward toward Canada's Hudson Bay. Approximately 10.6 million acres (42,900 km²) of wetlands are contained within Minnesota's borders, the most of any state except Alaska. 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「Geography of Minnesota」の詳細全文を読む スポンサード リンク
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