peneplain

peneplain
—peneplanation /pee'neuh pleuh nay"sheuhn/, n.
/pee"neuh playn', pee'neuh playn"/, n. Geol.
an area reduced almost to a plain by erosion.
Also, peneplane.
[1885-90; PENE- + PLAIN1]

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Gently undulating, almost featureless plain near sea level.

This would form, theoretically, by various erosional processes that reduce areas of initially high relief produced by active uplift to areas of virtually no relief. The lack of present-day peneplains tends to discredit the theory, but some geomorphologists propose that large areas of low relief at high altitude in some mountains are evidence of uplifted peneplains. Others question whether the dynamic relationship between erosion and rock type would ever allow the development of a peneplain, even over very long timespans.

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      gently undulating, almost featureless plain that, in principle, would be produced by fluvial erosion that would, in the course of geologic time, reduce the land almost to baselevel (sea level), leaving so little gradient that essentially no more erosion could occur. The peneplain concept was named in 1889 by William M. Davis (Davis, William Morris), who believed it to be the final stage of his geomorphic cycle of landform evolution.

      There has been much debate on the peneplain theory. The lack of present-day peneplains tends to discredit it, but some attribute this lack to geologically recent diastrophism, or uplifting, of the Earth's crust. Other geomorphologists question whether the Earth's crust has ever remained stable long enough for peneplanation to occur.

      Criteria considered by its proponents to be evidence for the theory are (1) the accordant summits, or remnants of an uplifted, dissected peneplain; (2) the occurrence of uniform truncation of strata of varying erosional resistance; and (3) the presence of remnants of a mantle of residual soil formed on the peneplain. Opponents of the theory hold that even if some examples do represent almost flat plains (which they consider unlikely), they were not necessarily formed by fluvial erosion within the confines of a geomorphic cycle.

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Universalium. 2010.

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Look at other dictionaries:

  • Peneplain —   [ pi:nɪpleɪn, englisch], Geomorphologie: Rumpffläche. * * * Pe|ne|plain [ pi:nɪpleɪn], die; , s [engl. peneplain, aus lat. pene, paene = fast u. engl. plain = Ebene] (Geogr.): Fastebene …   Universal-Lexikon

  • Peneplain — Pe ne*plain , n. [L. paene, pene, almost + E. plain.] (Phys. Geog.) A land surface reduced by erosion to the general condition of a plain, but not wholly devoid of hills; a base level plain. [Webster 1913 Suppl.] …   The Collaborative International Dictionary of English

  • peneplain — ☆ peneplain or peneplane [pē′nə plān΄, pen′əplān΄ ] n. [L pene, paene, almost (see PASSION) + PLAIN1, PLANE2] land worn down by erosion almost to a level plain …   English World dictionary

  • Peneplain — A peneplain is the final stage in fluvial or stream erosion.After the streams in an area have reached base level , lateral erosion is dominant as the streams erode the highland areas between them. Finally, the upland is almost gone: the stream… …   Wikipedia

  • Peneplain — Eine Peneplain (auch: Rumpffläche, Fastebene) ist eine durch Abtragung gebildete Verebnungsfläche auf gefaltetem oder stark gestörtem Untergrund. Sie deutet auf längere Zeiten tektonischer Ruhe in diesem Gebiet hin, da die starke Abschwächung des …   Deutsch Wikipedia

  • Peneplain — Pe|ne|plain* [ pi:niplein] die; , s <aus gleichbed. engl. peneplain, dies zu lat. pene, paene »fast« u. engl. plain »Ebene«> fast ebene Landoberfläche in geringer Höhe über dem Meeresspiegel, die nur von breiten Muldentälern u. niederen… …   Das große Fremdwörterbuch

  • peneplain — also peneplane noun Etymology: Latin paene, pene almost + English plain or plane Date: 1889 a land surface of considerable area and slight relief shaped by erosion …   New Collegiate Dictionary

  • peneplain — noun A region of faint or low relief, a based level plain …   Wiktionary

  • peneplain —    A degradation surface without relief [16] …   Lexicon of Cave and Karst Terminology

  • Peneplain — Pe|ne|plain 〈[pi:nıplɛın] f.; Gen.: , Pl.: s; Geogr.〉 durch abtragende Kräfte nahezu ebenes Gelände mit flachen Erhebungen u. sehr breiten Tälern [Etym.: engl.] …   Lexikalische Deutsches Wörterbuch

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