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The Uinta Mountains are an east-west trending chain of mountains in northeastern Utah extending slightly into southern Wyoming in the United States. As a subrange of the Rocky Mountains, they are unusual for being the highest range in the contiguous United States running east to west,〔(【引用サイトリンク】title=Kings Peak, Utah )〕 and lie approximately east of Salt Lake City. The range has peaks ranging from , with the highest point being Kings Peak, also the highest point in Utah. The Mirror Lake Highway crosses the western half of the Uintas on its way to Wyoming. ==Geology== The Uinta Mountains are Laramide uplifted metasedimentary rocks deposited in an intracratonic basin in southwest Laurentia during the time of the breakup of the supercontinent Rodinia. The marine and fluvial metasedimentary rocks in the core of the Uinta Mountains are of Neoproterozoic age〔(Paleomagnetic results from the Neoproterozoic Uinta Mountain Group )〕 (between about 700 million and 800 million years old) and consist primarily of quartzite, slate, and shale. These rocks comprise the Uinta Mountain Group, and reach thicknesses of . Most of the high peaks are outcrops of the Uinta Mountain Group. Many of the peaks are ringed with bands of cliffs, rising to form broad or flat tops.〔John McPhee, ''Basin and Range'', New York: Farrar, Straus, and Giroux, 1981, pp.198-199.〕 The mountains are bounded to the north and south by reverse faults that meet below the range, on the north by the North Flank fault and on the south by the Uinta Basin boundary fault. The Uinta Mountain Group from oldest to youngest includes Uinta Mountain unidivided quartz arenite, overlain by the Moosehorn Lake, Mount Watson, Hades Peak, and Red Shale formations. The flanks of the east-west trending Uinta Mountains contain a sequence of Paleozoic and Mesozoic strata ranging from the Cambrian Lodore Formation to the Cretaceous Mancos Shale, all of which have been tilted during the uplift of the mountain range. The uplift of the range dates to the Laramide orogeny, about 70 to 50 million years ago, when compressive forces produced high-angle reverse faults on both north and south sides of the present mountain range. The east-west orientation of the Uintas is anomalous compared to most of the ranges of the northern Rocky Mountains; it may relate to changing stress patterns and rotation of the Colorado Plateau.〔Hamilton, W.B., 1981, Plate-tectonic mechanism of Laramide deformation, in Boyd, D.W., and Lillegraven, J.A., eds., ''Rocky Mountain foreland basement tectonics: University of Wyoming Contributions to Geology'', v. 19, p. 87–92.〕 The high Uintas were extensively glaciated during the last ice age, and most of the large stream valleys on both the north and south sides of the range held long valley glaciers.〔(【引用サイトリンク】 url=http://geology.utah.gov/surveynotes/gladasked/gladglaciers.htm )〕 However, despite reaching to over in elevation, the climate today is sufficiently dry that no glaciers survived even before the rapid current glacial retreat began in the middle nineteenth century. The Uintas are the most poleward mountain range in the world to reach over without modern glaciers, and are in fact the highest mountain range in the contiguous United States with no modern glaciers. Permafrost occurs at elevations above 〔(Glacial Geology of the Northern Uinta Mountains )〕 and at times forms large rock glaciers. In between the summits and ridgelines are wide, level basins, with some 500 small lakes. One of the most popular lakes is Mirror Lake because of its good fishing, scenic views, and easy road access. 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「Uinta Mountains」の詳細全文を読む スポンサード リンク
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