Thermal segmentation of mid‐ocean ridge‐transform faults
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields

Dates

to

Document Data
Library
People
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page

The NOAA IR serves as an archival repository of NOAA-published products including scientific findings, journal articles, guidelines, recommendations, or other information authored or co-authored by NOAA or funded partners. As a repository, the NOAA IR retains documents in their original published format to ensure public access to scientific information.
i

Thermal segmentation of mid‐ocean ridge‐transform faults

Filetype[PDF-1.66 MB]



Details:

  • Journal Title:
    Geochemistry, Geophysics, Geosystems
  • Personal Author:
  • NOAA Program & Office:
  • Description:
    3-D finite element simulations are used to calculate thermal structures and mantle flow fields underlying mid-ocean ridge-transform faults (RTFs) composed of two fault segments separated by an orthogonal step over. Using fault lengths and slip rates, we derive an empirical scaling relation for the critical step over length ( urn:x-wiley:15252027:media:ggge21383:ggge21383-math-0001), which marks the transition from predominantly horizontal to predominantly vertical mantle flow at the base of the lithosphere under a step over. Using the ratio of step over length (LS) to urn:x-wiley:15252027:media:ggge21383:ggge21383-math-0002, we define three degrees of segmentation: first-degree, corresponding to type I step overs ( urn:x-wiley:15252027:media:ggge21383:ggge21383-math-0003 ≥ 3); second-degree, corresponding to type II step overs (1 ≤  urn:x-wiley:15252027:media:ggge21383:ggge21383-math-0004 < 3); and third-degree, corresponding to type III step overs ( urn:x-wiley:15252027:media:ggge21383:ggge21383-math-0005 <1). In first-degree segmentation, thermal structures and mantle upwelling patterns under a step over are similar to those of mature ridges, where normal mid-ocean ridge basalts (MORBs) form. The seismogenic area under first-degree segmentation is characteristic of two, isolated faults. Second-degree segmentation creates pull-apart basins with subdued melt generation, and intratransform spreading centers with enriched MORBs. The seismogenic area of RTFs under second-degree segmentation is greater than that of two isolated faults, but less than that of an unsegmented RTF. Under third-degree segmentation, mantle flow is predominantly horizontal, resulting in little lithospheric thinning and little to no melt generation. The total seismogenic area under third-degree segmentation approaches that of an unsegmented RTF. Our scaling relations characterize the degree of segmentation due to step overs along transform faults and provide insight into RTF frictional processes, seismogenic behavior, and melt transport.
  • Source:
    Geochemistry, Geophysics, Geosystems, 18(9), 3405-3418
  • DOI:
  • ISSN:
    1525-2027
  • Format:
  • Publisher:
  • Document Type:
  • Funding:
  • Rights Information:
    Other
  • Compliance:
    CHORUS
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at repository.library.noaa.gov

Version 3.27.1