Cutans are the modification of the soil texture , or soil structure , at natural surfaces particle, pore, or ped in soil materials due to illuvium illuviation . Cutans are oriented deposits ref cite web title Glossary of Soil Science Terms publisher Soil Science Society of America url http www.soils.org sssagloss index.php accessdate 2006 11 10 ref which can be composed of any of the component substances of the soil material. ref cite web url http www.ces.ncsu.edu plymouth programs ped.html title Pedological features author Richard Drees accessdate 2006 10 17 ref Cutans are common features in soil and represent focuses of chemical and biological reactions. Cutans may include clay skins or coatings of silica , sesquioxide , manganese , ferromanganese , soil organic matter or carbonate . ref cite web url http home.entouch.net dmd paleosol.htm title Paleosols author Jonathan Clark accessdate 2006 10 17 ref Clay skins are also called argillans, and soil horizons with sufficient clay illuviation are termed argillic horizons. Significance Cutans provide physical evidence, observable in the field, as to the degree and nature of pedogenesis . The ability to assess cutans is a core skill in soil morphology and paleopedology . See also Alfisols Soil profile References references Category Pedology Category Sedimentology ... more details
Refimprove date April 2009 Clay Cutans are a geologic fabric that develop around ancient cavities such as peds within paleosols . Formation Clay Cutans form by the coating of ancient open spaces by colloidal materials that were elluviated down from overlying horizons and are commonly stained by iron oxides such as hematite. While the originally openings are commonly lost through geologic time and diagenesis, the cutanic fabric remains as evidence. Cutans also often contain relics of Nodule geology nodules and skeleton grains . ref Retallack, G.J., 1988. Field recognition of paleosols. In Paleosols and weathering through geologic time Principles and Applications, Reinhardt, J. and Sigleo, W.R. eds. . Geological Society of America, Special Paper, 18 pp. ref They are one of the most diagnostic features of paleosols. Recognition Clay Cutans are most easily recognized under cross polarized light where they anisotropic . Cutans usually show lineations caused by the preferred orientation of clay minerals. Practical Significance Clay Cutans inherently indicate illuviation and therefore may indicate the presence of a petroleum seal in an underlying layer if silica had been transported to that depth. The J2 sandstone in Medicine River Gas Field in Alberta , Canada was cemented in such a manner. ref Wright, V.P., 1992. Paleosol recognition A guide to early diagenesis in terrestrial settings. In K.H. Wolf and G.V. Chilingarian Diagenesis III, Developments in Sedimentology 47, Elsevier Science Publishers B.V., 591 619. ref References reflist DEFAULTSORT Clay Cutan Category Pedology ... more details
Illuvium is material displaced across a soil profile , from one layer to another one, by the action of rainwater . The removal of material from a soil layer is called eluviation . The transport of the material may be either mechanical or chemical. The process of deposition of illuvium is termed illuviation . ref http www.physicalgeography.net physgeoglos i.html Glossary of Terms I Bot generated title ref It is a water assisted transport in a basically vertical direction, as compared to alluviation , the horizontal running water transfer. The resulting deposits are called illuvial deposits . Cutans are a type of illuvial deposit. ref cite web title Glossary of Soil Science Terms publisher Soil Science Society of America url http www.soils.org sssagloss index.php accessdate 2006 11 10 ref Illuvium includes organic matter , silicate clay , and hydrous oxide s of iron and aluminum . Illuvial deposits of clays, oxides, and organics accumulate in subsoil as distinctive soil horizon s classified as B horizons or zones of illuviation . Mechanical illuviation When percolating precipitation meteorology rain water reaches a drier soil horizon, water from the suspension chemistry suspension is removed by capillary action of microchannels, leaving fine deposition chemistry deposits cutans oriented along percolation macrochannels. Examples Mesara Plain , Crete , Greece Chemical illuviation Transport of soil solutes is termed Leaching pedology leaching . Soluble constituents are deposition chemistry deposited due to differences in soil chemistry , especially soil pH and redox potential . References div class references small references div See also Alluvium Eluvium Colluvium Diluvium Category Pedology Category Sedimentology es Iluviaci n fr Illuviation it Illuviazione pt Iluvi o ru uk ... more details
image Slickensides juniata.jpg thumb Slickensides on a sample of sandstone of the Juniata Formation , from an outcrop on U.S. Route 322 Rt 322 northeast of State College, Pennsylvania image Slicks.jpg 250px thumb left How slickenfibre steps form and show sense of movement on a fault File PySlick.JPG thumb Dextral slickenside of pyrite image Slickensides.JPG 200px thumb right Slickensides developed on the surface of a small Fault geology fault in quartzite in the Alpujarras Image Bear Valley Slickensides.jpg thumb left Slickensides on a fault plane, south wall of Bear Valley Strip Mine . Lens cap 5.8cm wide. In geology , a slickenside is a smoothly polished surface caused by frictional movement between Rock geology rocks along the two sides of a fault geology fault . This surface is normally striated in the direction of movement. The plane may be coated by mineral fibres that grew during the fault movement, known as slickenfibres , which also show the direction of displacement. Due to irregularities in the fault plane exposed slickenfibres typically have a stepped appearance that can be used to determine the sense of movement across the fault. The surface feels smoother when the hand is moved in the same direction that the eroded side of the fault moved see diagram for explanation , as the surface steps down in that direction, like the scales on a fish when stroked from the head. In pedology soil study pedology , the study of soil s in their natural environments, a slickenside is a surface of the cracks produced in soils containing a high proportion of swelling clay s. Slickensides are a type of Cutans cutan . commonscat Slickensides References Allaby, A. and Allaby, M. Eds . 1990. The Concise Oxford Dictionary of Earth Sciences . New York, USA Oxford University Press. McDonald, R. C. et al. 1990. The Australian Soil and Land Survey Field Handbook , 2nd Ed. Melbourne, Australia Inkata Press. Microtectonics , by C.W.Passchier and R.A.J.Trouw, 2nd rev. and enlarged ed. ... more details
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