CUTANS (also see SUBCUTANIC FEATURES)
Cutan. A modification of the texture, structure, or fabric at natural surfaces in soil materials due to concentration of particular soil constituents or in situ modification of the plasma; cutans can be composed of any of the component substances of the soil material.
Diffusion Cutans. Concentrations at a surface due to diffusion; usually associated with concentrations within the s-matrix of the soil material that reach a maximum at the cutanic surface.
Illuviation Cutans. Formed by movement of the cutanic material in solution or suspension and subsequent deposition.
Stress Cutans. In situ modifications of the plasma due to differential forces such as shearing; they are not true coatings.
1. CHARACTERISTICS of SURFACES AFFECTED
Grains Cutans. Cutans associated with the surfaces of skeleton grains or other discrete units; such as nodules, concretions, etc.
Free Grain Cutans. Occur on the surfaces of grains which form the walls of voids.
Embedded Grain Cutans. Occur on surfaces of grains embedded in relatively densely packed plasma.
Ped Cutans. Associated with the surfaces of peds.
Channel Cutans. Associated with the walls of channels whether these are of biological origin (worm channels) or not.
Plane Cutans. Assocated with walls of planar voids other than those between peds.
Normal Void Cutans. Associated with the walls of the normal equant, triaxial, and prolate voids within primary peds or in apedal soil material.
2. MINERALOGICAL NATURE of CUTANIC MATERIAL
Argillan. A cutan composed dominantly of silicate clay minerals.
Ferri-argillan. A cutan composed of intimately mixed clay minerals and iron oxides or hydroxides, whos color depends on the degree of hydration and oxidation of the iron oxides and hydroxides.
Organo-arillan. A cutan composed of clay minerals stained by organic compounds.
Sesquan. A cutan composed of a concentration of sesquioxides or hydroxides.
Mangan. A cutan containing enough manganese (oxides or hydroxides) to effervesce upon application of hydrogen peroxide.
Soluan. A cutan consisting of crystalline salts, such as carbonates, sulfates, and chlorides of Ca, Mg, and Na.
Calcan. A cutan composed of carbonates (e.g. calcitans).
Gypsum. A cutan composed of gypsum.
Halan. A cutan composed of salt (halite).Silan. A cutan composed of silica in its various forms, such as silt or clay size quartz or chalcedony.
Skeletan. A cutan composed of skeleton grains adhering to cutanic surfaces.
Alban. A cutan composed of materials that have been strongly reduced.
Ferran a cutan composed of a concentration of iron oxides.
Matran. A cutan that contains s-matrix skeleton grains within the plasma concentration.
Organan. A cutan composed of a concentration of organic matter.
GLAEBULES
Glaebules. A three dimensional unit within the s-matrix of the soil material, and usually approximately prolate to equant in shape. Its morphology (size, shape, and/or internal fabric) is incompatible with its present occurrence being within a single void in the present soil matrial.
Concretions. Glaebules with a generally concentric fabric about a center which may be a point, a line, or a plane.
Nodules. Glaebules with an undifferentiated internal fabric; in this context undifferentiated fabric unclueds recognizable rock and soil fabrics.
Papules. Galebules composed dominantly of clay minerals with continuous and/or lamellar fabric.
Pedodes. Glaebules with a hollow interior, often with a drusy lining of crystals.
Septeria. Glaebules with a series of radiating cracks crossed by a series of cracks concentric with the margins; the crack pattern is often highly irregular; they are usually spheroidal with sharp boundaries.CRYSTALLARIA
Glaebule. A three dimensional unit within the s-matrix of the soil material, and usually approximately prolate to equant in shape. Its morphology (size, shape, and/or internal fabric) is incompatible with its present occurrence being within a single void in the present soil material.
Concretions. Glaebules with a generally concentric fabric about a center which may be a point, a line, or a plane.
Nodules. Glaebules with an undifferentiated internal fabric; in this context undifferentiated fabric includes regognizable rock and soil fabrics.
Papules. Glaebules composed dominantly of clay minerals with continuous and/or lamellar fabric.
Pedodes. Glaebules with a hollow interior, often with a drusy lining of crystals.
Septeria. Glaebules with a series of radiating cracks crossed by a series of cracks concentric with the margins; the crack pattern is often highly irregular; they are usually spheroidal with sharp boundaries.CRYSTALLARIA
Crystallaria. Single crystals, or arrangement of crystals of relatively pure fractions of the plasma that do not enclose the s-matrix of the soil material but form coherent masses. Crystallaria cna be composed of any of the chemical compounds derived from the soil constituents that can be crystallize from solution (calcite, gypsum, halite, barite, etc.).
Crystal Tubes. Crystallaria that occur in channels of simple or branching acicular shape. Often growing inward to fill a void.
Crystal Chambers. Usually prolate to equant crystallaria formed in vughs, vesicles, and chambers.
Crystal Sheets. Planar shaped crystallaria formed in planes.
Intercalary Crystals. Crystallaria thaat consist of single large crystals or groups of a few large crystals set in the soil material and apparently not associated with voids of equivalent size or shape to that of the crystallaria as a whole; the crystals are euhedral to subhedral having at least some well developed crystal faces.SUBCUTANIC FEATURES
Subcutanic Feature. A pedological feature (recognized by a difference in texture, structure, or fabric as compared with the enclosing s-matrix) that has a consistent relationship with natural surfaces in the soil material, but does not occur immediately at the surface.
Neocutans. These occur subcutanically immediately adjoining the natural surfaces with which they are associated. As example, neocalcans, neosesquans. All neocutans are usually strongly adhesive.
Quasicutans. These occur immediately subcutanically to natural surfaces but not immediately adjoining them; they have some obvious relationship to natrual surfaces in regard to shape and distribution but do not occur adjacent to the surface.The majority of neocutans and quasicutans are plasma concentrations.
PEDOTUBULES
Pedotubleu. A pedological feature consiting of soil material (skeleton grains plus plasma) and having a tubular external form; the external boundaries are relatively sharp.
Internal Fabric Compostition
Granotubules. Pedotubules composed essentially of skeleton grains without plasma, or all the plasma occurs as pedological features.
Aggrotubules. Pedotubules composed of skeleton grains and plasma which occur essentially as recognizable aggregates within which there is no directional arrangement with regard to the external form.
Isotubules. Pedotubules composed of skeleton grains and plasma that are not organized into recognizable aggregates and within which the basic fabric shows no directional arrangement with regard to the external form.
Striotubules. Pedotubules composed of skeleton grains and plasma that are not organized into recognizable aggregates but exhibit a basic babric with a directional arrangement related to the external form.
This page (http://www.ces.ncsu.edu/plymouth/programs/ped.html) created by
Vera MacConnell, Research Technician, I on January 14, 1998.
Last Updated on January 14, 1998.
