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An ice rise is a clearly defined elevation of the otherwise totally flat ice shelf, typically dome-shaped and rising 100 to 200 metres above the surrounding ice shelf. An ice rise forms where the ice shelf touches the rocky seabed because of an elevation in the seabed that remains below sea level. (In contrast, an elevation in the seabed that extends above sea level is defined as an island). The ice shelf flows over the seabed elevation, completely covering it with ice, thereby forming an ice rise. The resulting tension forms crevasses around the ice rise. An island within and totally covered by the ice shelf, may appear the exactly the same as an ice rise. Elaborate measurements may be required to distinguish between these two geographic features. Although ice rises are typically located within the ice shelf area, they can partially face the open sea. Ice rises are found only on the ice shelves of Antarctica, mostly on Ronne Ice Shelf. The largest ice rises exceed dimensions of 50 by 200 km, or 10 000 km² in area. Some ice rises are incorrectly called islands, but also a few totally ice-covered islands within an ice shelf are also called ice rises. Ice rises, grouped by ice shelf, clockwise starting in East Antarctica: *Brunt Ice Shelf * *McDonald Ice Rumples *Riiser-Larsen Ice Shelf * *Lyddan Island *Amery Ice Shelf * *Budd Ice Rumples * * IR1 to IR5 near the ice front〔Fricker et al., 2009, doi:10.1017/S095410200999023X〕 *Shackleton Ice Shelf * *Green Ice Rises (the northernmost ice rise, at 66°21'S) * *Harrisson Ice Rises *Ross Ice Shelf * *Crary Ice Rise (the southernmost ice rise, at 82°56'S) *Crosson Ice Shelf * *Davis Ice Rise *Bach Ice Shelf * *Burgess Ice Rise * *Dvořák Ice Rise * *Ives Ice Rise *George VI Ice Shelf * *Martin Ice Rise *Wilkins Ice Shelf * *Petrie Ice Rises * *Schaus Ice Rises * *Vere Ice Rise *Wordie Ice Shelf * *Coker Ice Rise * *Linchpin Ice Rise * *Miller Ice Rise * *Napier Ice Rise * *Reynolds Ice Rise * *Wade Ice Rise *Müller Ice Shelf * *Humphreys Ice Rise *Larsen-C Ice Shelf * *Bawden Ice Rise * *Gipps Ice Rise * *Tharp Ice Rise *Filchner-Ronne Ice Shelf * *Berkner Island * *Korff Ice Rise * *Henry Ice Rise * *Fowler Ice Rise * *Skytrain Ice Rise * *Doake Ice Rumples * *Dott Ice Rise * *Fletcher Ice Rise * *Hemmen Ice Rise * *Kealey Ice Rise * *Kershaw Ice Rumples Henry and Korff Ice Rises are the largest ice rises, with areas of roughly 1 500 to 1 600 km². ==References== 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「ice rise」の詳細全文を読む スポンサード リンク
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