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An inselberg or monadnock is an isolated rock hill, knob, ridge, or small mountain that rises abruptly from a gently sloping or virtually level surrounding plain. In southern and south-central Africa, a similar formation of granite is known as a ''koppie'', an Afrikaans word ("little head") from the Dutch word ''kopje''.〔''Webster's New Explorer Dictionary of Word Origins'' (2004). Federal Street Press: New York.〕 If the inselberg is dome-shaped and formed from granite or gneiss, it can also be called a bornhardt, albeit not all bornhardts are inselbergs. ==Definitions== The word ''inselberg'' is German for "island mountain"; the name was originally coined by geologist Wilhelm Bornhardt (1864–1946) in 1900 to describe the abundance of such features found in southern Africa.〔Holmes, Arthur '' (1978). (Holmes Principles of Physical Geology )'' Taylor & Francis: New York.〕 At that time, the term applied only to arid landscape features. However, the term inselberg has since been used to describe a broader geography and range of rock features, leading to confusion about the precise definition of the term. In a 1973 study examining the use of the term, one researcher found that the term had been used for features in savannah climates 40% of the time; arid or semi-arid climates 32% of the time; humid-subtropical and arctic 12% of the time; and 6% each for humid-tropical and Mediterranean climates. As recently as 1972, the term has been defined as "steep-sided isolated hills rising relatively abruptly above gently sloping ground." This definition includes such features as buttes; conical hills with rectilinear sides typically found in arid regions; regolith-covered concave-convex hills; rock crests over regolith slopes; rock domes with near vertical sides; tors (koppies) formed of large boulders but with solid rock cores. Thus, the terms monadnock and inselberg may not perfectly match,〔Gerrard, John (1988). ''(Rocks and Landforms )'' Routledge: Florence, Kentucky.〕 though equally, some authors have explicitly argued these terms are in fact completely synonymous.〔King, L.C., 1953, Canons of landscape evolution: Bulletin of the Geological Society of America, v. 64, no. 7, p. 721–752.〕 ''Monadnock'' is an originally Native American term for an isolated hill or a lone mountain that stands above the surrounding area, typically by surviving erosion. Geologists took the name from Mount Monadnock in southwestern New Hampshire.〔Raymo, Chet and Raymo, Maureen E. (1989) ''Written in Stone: A Geologic History of the Northeastern United States.'' Globe Pequot, Chester, Connecticut.〕 It is thought to derive from the Abenaki language, from either ''menonadenak'' ("smooth mountain") or ''menadena'' ("isolated mountain").〔"(Vermont Soils with Names of American Indian Origin )" United States Department of Agriculture, Natural Resources Conservation Service. Retrieved January 6, 2008.〕 In this context, ''monadnock'' is used to describe a mountain that rises from an area of relatively flat and/or lower terrain. For instance, Mount Monadnock rises above its surrounding terrain and stands, at , nearly higher than any mountain peak within .〔Baldwin, Henry I. (1989). ''Monadnock Guide 4th edition.'' Concord, New Hampshire: Society for the Protection of New Hampshire Forests.〕 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「Inselberg」の詳細全文を読む スポンサード リンク
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