Thermal structure of oceanic transform faults
MetadataShow full item record
KeywordOceanic transform faults; Mid-ocean ridges; Fault rheology; Intratransform spreading centers
We use three-dimensional finite element simulations to investigate the temperature structure beneath oceanic transform faults. We show that using a rheology that incorporates brittle weakening of the lithosphere generates a region of enhanced mantle upwelling and elevated temperatures along the transform; the warmest temperatures and thinnest lithosphere are predicted to be near the center of the transform. Previous studies predicted that the mantle beneath oceanic transform faults is anomalously cold relative to adjacent intraplate regions, with the thickest lithosphere located at the center of the transform. These earlier studies used simplified rheologic laws to simulate the behavior of the lithosphere and underlying asthenosphere. We show that the warmer thermal structure predicted by our calculations is directly attributed to the inclusion of a more realistic brittle rheology. This temperature structure is consistent with a wide range of observations from ridge-transform environments, including the depth of seismicity, geochemical anomalies along adjacent ridge segments, and the tendency for long transforms to break into small intratransform spreading centers during changes in plate motion.
Author Posting. © Geological Society of America, 2007. This article is posted here by permission of Geological Society of America for personal use, not for redistribution. The definitive version was published in Geology 35 (2007): 307-310, doi:10.1130/G23112A.1.
Suggested CitationGeology 35 (2007): 307-310
Showing items related by title, author, creator and subject.
Trehu, Anne M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982-02)In this thesis, seismic waves generated by sources ranging from 2.7 kg shots of TNT to magnitude 5 earthquakes are studied in order to determine the seismic activity and crustal structure of the Orozco transform fault. ...
The dynamics of oceanic transform faults : constraints from geophysical, geochemical, and geodynamical modeling Gregg, Patricia M. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2008-06)Segmentation and crustal accretion at oceanic transform fault systems are investigated through a combination of geophysical data analysis and geodynamical and geochemical modeling. Chapter 1 examines the effect of fault ...
Roland, Emily C. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2012-02)Oceanic transform faults that accommodate strain at mid-ocean ridge offsets represent a unique environment for studying fault mechanics. Here, I use seismic observations and models to explore how fault structure affects ...