foliation

foliation

English

Foliation (property of being divided into layers) in a metamorphic rock (gneiss)

Etymology

From French foliation, from Latin folium (“leaf”).

Pronunciation

• (Received Pronunciation)
  • IPA^(key): /fəʊlɪˈeɪʃn/

• Audio (Southern England)

  (file)

• Rhymes: -eɪʃən

Noun

foliation (countable and uncountable, plural foliations)

1. (botany) The process of forming into a leaf or leaves.
2. (publishing) The process of forming into pages; pagination.
3. (botany) The manner in which the young leaves are disposed within the bud.
4. The act of beating a metal into a thin plate, leaf, foil, or lamina.
5. The act of coating with an amalgam of tin foil and quicksilver, as in making looking-glasses.
6. The enrichment of an opening by means of foils, arranged in trefoils, quatrefoils, etc.; also, one of the ornaments.
   • 1907 August, Robert W[illiam] Chambers, chapter I, in The Younger Set, New York, N.Y.: D. Appleton & Company, OCLC 24962326:

     The house was a big elaborate limestone affair, evidently new. Winter sunshine sparkled on lace-hung casement, on glass marquise, and the burnished bronze foliations of grille and door.

7. (geology) The property, possessed by some crystalline rocks, of being divided into plates or layers, due to the cleavage structure of one of the constituents, as mica or hornblende. It may sometimes include slaty structure or cleavage, though the latter is usually independent of any mineral constituent, and transverse to the bedding, it having been produced by pressure.
   • 1983, Warren C. Day, Richard M. Tosdal, E.L. Acosta, J.C. Aruspon, L. Carvajal, E. Cedeño, Glenda Lowry, L.F. Martinez, J.A. Noriega, Fernanco J. Niñez, J. Rojas, F. Prieto, “Geology of the Lo Indreíble Mining District and U-Pb Age of the Early Proterozoic Yuruari Formation of the Pastora Supergroup, Guayana Shield, Venezuela”, in U.S. Geological Survey Bulletin, number 2122-2127, page E-12:

     Formation of alteration minerals in the host rock during deformation within the shear zone is indicated by the parallel foliation within the secondary micaceous minerals and the unmineralized host schist.

   • 1993, Charles A. Baskerville, Fitzhugh T. Lee, Charles A. Ratté, Landslide Hazards in Vermont, U.S. Geological Survey Bulletin 2043, p.18:

     The dominant strike orientation of both bedding and foliation of Vermont bedrock is north or northeasterly.

   • 1996, Eric C. Beam, Modeling Growth and Rotation of Porphyroblasts and Inclusion Trails, D.G. De Paor, Structural Geology and Personal Computers, p.249:

     They show that curved inclusion trails may form even with no coupling, as the porphyroblast overgrows foliation that is deflected around it.

   • 2004, F. Martín-Hernández, C. M. Lüneburg, C. Aubourg, M. Jackson, Magnetic fabric: methods and applications - an introduction, Geological Society of London, Magnetic Fabric: Methods and Applications, p.3:

     In sedimentary rocks, the magnetic foliation results from a combination of depositional processes and diagenetic compaction.

8. (topology) A set of submanifolds of a given manifold, each of which is of lower dimension than it, but which, taken together, are coextensive with it.
   • 1992, R. C. Penner, Combinatorics of Train Tracks‎, page 204:

     Historically, the formalism which first arose for the material we discuss is that of measured foliations in surfaces.

   • 2003, Alberto Candel, Lawrence Conlon, Foliations, Vol.2, p.253:

     We will show that every closed 3-manifold has a foliation of codimension one. In 1952, G. Reeb published his construction of a foliation of the 3-sphere. About twelve years later, W. Lickorish [123] exhibited foliations of codimension one on every closed, orientable 3-manifold.

   • 2004, Paweł Grzegorz Walczak, Dynamics Of Foliations, Groups And Pseudogroups, Monografie Matematyczne: Vol.64, New Series, p.6:

     The simplest example of a foliation is provided by a single submersion F : M → N, M and N being manifolds.

Synonyms

• (process of forming pages): pagination
• (growth and arrangement of leaves): vernation

Related terms

• defoliation
• exfoliate
• exfoliation
• foliate
• folio
• folium
• refoliation

Translations

topology: a set of subspaces coextensive with a manifold

Chinese: 叶层结构 (yè céng jiégòu) Danish: foliering c French: feuilletage (fr) m German: Blätterung f Portuguese: folheação f Russian: листоватость f (listovatostʹ) Spanish: foliación f

See also

• cleavage (geology)
• lineation (geology)

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French

Noun

foliation f (plural foliations)

1. (botany) foliation
2. (geology) foliation

Further reading

• “foliation”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.