transform fault


  • Wilson described six types of transform faults: Growing length: In situations where a transform fault links a spreading center and the upper block of a subduction zone or
    where two upper blocks of subduction zones are linked, the transform fault itself will grow in length.

  • Instead of the ridges moving away from each other, as they do in other strike-slip faults, transform-fault ridges remain in the same, fixed locations, and the new ocean seafloor
    created at the ridges is pushed away from the ridge.

  • In time as the plates are subducted, the transform fault will decrease in length until the transform fault disappears completely, leaving only two subduction zones facing
    in opposite directions.

  • Spreading center and strips Transform faults move differently from a strike-slip fault at the mid-oceanic ridge.

  • [5] Finally, when two upper subduction plates are linked there is no change in length.

  • Types In his work on transform-fault systems, geologist Tuzo Wilson said that transform faults must be connected to other faults or tectonic-plate boundaries on both ends;
    because of that requirement, transform faults can grow in length, keep a constant length, or decrease in length.

  • Both types of fault are strike-slip or side-to-side in movement; nevertheless, transform faults always end at a junction with another plate boundary, while transcurrent faults
    may die out without a junction with another fault.

  • Slip along transform faults does not increase the distance between the ridges it separates; the distance remains constant in earthquakes because the ridges are spreading centers.

  • Fracture zones represent the previously active transform-fault lines, which have since passed the active transform zone and are being pushed toward the continents.

  • This is due to the plates moving parallel with each other and no new lithosphere is being created to change that length.

  • The new class of faults,[5] called transform faults, produce slip in the opposite direction from what one would surmise from the standard interpretation of an offset geological

  • Although separated only by tens of kilometers, this separation between segments of the ridges causes portions of the seafloor to push past each other in opposing directions.

  • [1] It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone.

  • [2] A transform fault is a special case of a strike-slip fault that also forms a plate boundary.

  • A smaller number of such faults are found on land, although these are generally better-known, such as the San Andreas Fault and North Anatolian Fault.

  • Nomenclature Transform boundaries are also known as conservative plate boundaries because they involve no addition or loss of lithosphere at the Earth’s surface.

  • In New Zealand, the South Island’s alpine fault is a transform fault for much of its length.

  • Known as the St. Paul, Romanche, Chain, and Ascension fracture zones, these areas have deep, easily identifiable transform faults and ridges.

  • These elevated ridges on the ocean floor can be traced for hundreds of miles and in some cases even from one continent across an ocean to the other continent.


Works Cited

[‘o Moores E.M.; Twiss R.J. (2014). Tectonics. Waveland Press. p. 130. ISBN 978-1-4786-2660-2.
o ^ Kearey, K. A. (2007). Global Tectonics. Hoboken, NJ, USA: John Wiley & Sons. pp. 84–90.
o ^ British Geological Survey (2020). “Plate Tectonics”. Retrieved
16 February 2020.
o ^ Reid, H.F., (1910). The Mechanics of the Earthquake. in The California Earthquake of April 18, 1906, Report of the State Earthquake Investigation Commission, Carnegie Institution of Washington, Washington D.C.
o ^ Jump up
to:a b c d e f Wilson, J.T. (24 July 1965). “A new class of faults and their bearing on continental drift”. Nature. 207 (4995): 343–347. Bibcode:1965Natur.207..343W. doi:10.1038/207343a0. S2CID 4294401.
o ^ Sykes, L.R. (1967). Mechanism of earthquakes
and nature of faulting on the mid-oceanic ridges, Journal of Geophysical Research, 72, 5–27.
o ^ Gerya, T. (2010). “Dynamical Instability Produces Transform Faults at Mid-Ocean Ridges”. Science. 329 (5995): 1047–1050. Bibcode:2010Sci…329.1047G.
doi:10.1126/science.1191349. PMID 20798313. S2CID 10943308.
o ^ Jump up to:a b Bonatti, Enrico; Crane, Kathleen (1984). “Oceanic Fracture Zones”. Scientific American. 250 (5): 40–52. Bibcode:1984SciAm.250e..40B. doi:10.1038/scientificamerican0584-40.
o ^
Jump up to:a b c Atwater, Tanya (1970). “Implications of Plate Tectonics for the Cenozoic Tectonic Evolution of Western North America”. Bulletin of the Geological Society of America. 81 (12): 3513–3536. Bibcode:1970GSAB…81.3513A. doi:10.1130/0016-7606(1970)81[3513:ioptft];2.

Photo credit:’]