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The Lower Permian Esplanade Sandstone is a cliff-forming, resistant sandstone, dark red, geologic unit found in the Grand Canyon. The rock unit forms a resistant shelf in the west Grand Canyon, south side of the Colorado River, at the east of the Toroweap Fault, down-dropped to west, southeast of Toroweap Overlook (North Rim, at Lava Falls), and west of Havasupai. The red, sandstone shelf, The Esplanade is about 20-mi long. At Toroweap Overlook region, Toroweap Valley with Vulcan's Throne, Uinkaret volcanic field, the resistant Esplanade Sandstone is described in access routes exploring the Toroweap Lake area (Hike 17, Vulcans Throne).〔Lucchitta, 2001. ''Hiking Arizona's Geology'', Hike 17, Vulcans Throne, pp. 138-142.〕 The Esplanade Route-(trail), of the east Grand Canyon is also named for the Esplanade Sandstone. The coeval sandstone geologic unit from eastern Utah is the Cedar Mesa Sandstone.〔Blakey, Ranney, 2008. ''Ancient Landscapes of the Colorado Plateau'', pp. 42, 43-(map, 287 Ma).〕 ==Isis Temple and Hermosa Group, Utah== In Grand Canyon, Isis Temple landform, north of Grand Canyon Village (South Rim, 5-mi), contains a representative example of the Supai Group 'redbeds', and slope-former and cliff-former units that support the landform. The sequence of units below the white Coconino Sandstone prominence of Isis Temple are: * G-Coconino Sandstone-''white prominence'' ('white'-ridgeline to right is from North Rim, ~1.5 mi distant) * F-Hermit Formation-grayish slopes * E-Supai Group * * 4-Esplanade Sandstone-cliff-former * * 3-Wescogame Formation * * 2-Manakacha Formation * * 1-Watahomigi Formation * D-Redwall Limestone-large red cliff * C-Muav Limestone-''grayish-cliff'' (attached at base of Redwall cliffs-40%) * B-(''light-greenish slope-former'')-Bright Angel Shale * A-upon (''dk brown massive cliffs'')-Shinumo Quartzite The Esplanade Sandstone is only found in Arizona, with the Hermosa Group being the equivalent coeval 'redbed' type geologic sequence found north and northeasterly in Utah-(parts of western border Colorado). 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「Esplanade Sandstone」の詳細全文を読む スポンサード リンク
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