Encyclopedia of Solid Earth Geophysics

Living Edition
| Editors: Harsh K. Gupta

Earthquakes on Oceanic Transform Faults, Unexpectedly Large

Living reference work entry
DOI: https://doi.org/10.1007/978-3-030-10475-7_239-1


Transform faults are conservative plate boundaries, where material is neither created nor destroyed. The most prominent of these worldwide are oceanic transform faults such as the mid-ocean ridges.


One of the key pieces of evidence that supported the theory of plate tectonics in the 1960s was the explanation of how plates move along mid-oceanic transform faults (Wilson 1965). The six possible types of dextral (right-lateral) transform faults are shown in Fig. 1a. Six sinistral (left-lateral) transform faults, which are mirror images of the ones plotted, also can exist. The appearance of the right-lateral systems after a period of growth is shown in Fig. 1b. Note that length of the active transform fault is growing in three cases, decreasing in one case, and indeterminate in two cases, as indicated in Fig. 1b.
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Authors and Affiliations

  1. 1.Department of Earth SciencesUniversity of OxfordOxfordUK