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tafoni
tafoni Tafoni (singular tafone) are typically cavernous weathering features which can be up to several metres in height, width, and depth. They have arch-shaped entrances, concave inner walls, overhanging upper margins (visors), and smooth, gently sloping debris-covered floors. These landforms are found in many parts of the world, particularly in semi-arid and coastal environments, and in a variety of topographic situations. They also develop in a variety of rock types but more especially in medium- to coarse-grained lithologies including granites, sandstones, and limestones.
The origin of tafoni is complex and appears to involve a combination of different processes operating on different parts of the landform, although the marked similarity of form suggests a similarity of origin and development between regions. The cavernous hollows appear to result from hydration, dissolution, and re-precipitation of calcareous and saline cements, wetting and drying, rain-wash, and wind deflation, while the smooth and often rounded outer surfaces appear to develop through near-surface cementation, thermal expansion and contraction, and formation of surface varnish. Although many tafoni are undergoing active development today, this is not always the case and some appear to be relics inherited from a different weathering environment in the past. A. Mellor |
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Cite this article
PAUL HANCOCK and BRIAN J. SKINNER. "tafoni." The Oxford Companion to the Earth. 2000. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. PAUL HANCOCK and BRIAN J. SKINNER. "tafoni." The Oxford Companion to the Earth. 2000. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O112-tafoni.html PAUL HANCOCK and BRIAN J. SKINNER. "tafoni." The Oxford Companion to the Earth. 2000. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O112-tafoni.html |
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tafoni
tafoni A hollow, produced by localized weathering on a steep face. Rock breakdown typically takes place by granular disintegration or by flaking, and the hollow shows a tendency to grow upwards and backwards.
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Cite this article
AILSA ALLABY and MICHAEL ALLABY. "tafoni." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "tafoni." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O13-tafoni.html AILSA ALLABY and MICHAEL ALLABY. "tafoni." A Dictionary of Earth Sciences. 1999. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-tafoni.html |
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tafoni
tafoni A hollow, produced by localized weathering on an exposed rock face. The rock usually breaks down by granular disintegration or by flaking and the hollow tends to grow upwards and backwards.
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Cite this article
MICHAEL ALLABY. "tafoni." A Dictionary of Ecology. 2004. Encyclopedia.com. 1 Jun. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "tafoni." A Dictionary of Ecology. 2004. Encyclopedia.com. (June 1, 2012). http://www.encyclopedia.com/doc/1O14-tafoni.html MICHAEL ALLABY. "tafoni." A Dictionary of Ecology. 2004. Retrieved June 01, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-tafoni.html |
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