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Oceanic transform fault seismicity and slip mode influenced by seawater infiltration

Nature Geoscience volume 14, pages 606–611 (2021)Cite this article

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Abstract

Oceanic transform faults that offset mid-ocean ridges slip through earthquakes and aseismic creep. The mode of slip varies with depth and along strike, with some fault patches that rupture in large, quasi-periodic earthquakes at temperatures <600 °C, and others that slip through creep and microearthquakes at temperatures up to 1,000 °C. Rocks from both fast- and slow-slipping transforms show evidence of interactions with seawater up to temperatures of at least 900 °C. Here we present a model for the mechanical structure of oceanic transform faults based on fault thermal structure and the impacts of hydration and metamorphic reactions on mantle rheology. Deep fluid circulation is accounted for in a modified friction-effective pressure law and in ductile flow laws for olivine and serpentine. Combined with observations of grain size reduction and hydrous mineralogy from high-strain mylonites, our model shows that brittle and ductile deformation can occur over a broad temperature range, 300–1,000 °C. The ability of seawater to penetrate faults determines whether slip is accommodated at depth by seismic asperities or by aseismic creep in weak, hydrous shear zones. Our results suggest that seawater infiltration into ocean transform faults controls the extent of seismicity and spatiotemporal variations in the mode of slip.

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Fig. 1: Map and microstructures of OTF mylonites.
Fig. 2: Thermal models and hydrous mineralogy of OTFs.
Fig. 3: Strength–depth profiles for slow- and fast-slipping OTFs.
Fig. 4: Vertical and along-strike variations in seismicity on OTFs.

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Data availability

OTF mylonite and OBS deployment locations are provided in Supplementary Information Table 1. OTF mylonite compositional data is available at EarthChemLibrary48. The Gofar seismic data is available from the IRIS Data Management Center (https://www.fdsn.org/networks/detail/ZD_2007/). Source data are provided with this paper.

Code availability

The codes used to generate the thermal models, deformation mechanism maps and strength–depth profiles can be accessed at https://github.com/ahkohli/OTFs.

References

  1. Wiens, D. A. & Stein, S. Age dependence of oceanic intraplate seismicity and implications for lithospheric evolution. J. Geophys. Res. 88, 6455–6468 (1983).

    Article  Google Scholar 

  2. Chen, W.-P. & Molnar, P. Focal depths of intracontinental and intraplate earthquakes and their implications for the thermal and mechanical properties of the lithosphere. J. Geophys. Res. 88, 4183–4214 (1983).

    Article  Google Scholar 

  3. Abercrombie, R. E. & Ekström, G. Earthquake slip on oceanic transform faults. Nature 410, 74–77 (2001).

    Article  Google Scholar 

  4. Boettcher, M. S., Hirth, G. & Evans, B. Olivine friction at the base of oceanic seismogenic zones. J. Geophys. Res. 112, B01205 (2007).

    Google Scholar 

  5. McGuire, J. J. et al. Variations in earthquake rupture properties along the Gofar transform fault, East Pacific Rise. Nat. Geosci. 5, 336–341 (2012).

    Article  Google Scholar 

  6. Roland, E., Lizarralde, D., McGuire, J. J. & Collins, J. A. Seismic velocity constraints on the material properties that control earthquake behavior at the Quebrada–Discovery–Gofar transform faults, East Pacific Rise. J. Geophys. Res. 117, B11102 (2012).

    Google Scholar 

  7. Wolfson-Schwehr, M., Boettcher, M. S., McGuire, J. J. & Collins, J. A. The relationship between seismicity and fault structure on the Discovery transform fault, East Pacific Rise. Geochem. Geophys. Geosyst. 15, 3698–3712 (2014).

    Article  Google Scholar 

  8. Kuna, V. M., Nábělek, J. L. & Braunmiller, J. Mode of slip and crust–mantle interaction at oceanic transform faults. Nat. Geosci. 12, 138–142 (2019).

    Article  Google Scholar 

  9. Froment, B. et al. Imaging along-strike variations in mechanical properties of the Gofar transform fault, East Pacific Rise. J. Geophys. Res. 119, 7175–7194 (2014).

    Article  Google Scholar 

  10. Guo, H., Zhang, H. & Froment, B. Structural control on earthquake behaviors revealed by high-resolution Vp/Vs imaging along the Gofar transform fault, East Pacific Rise. Earth Planet. Sci. Lett. 499, 243–255 (2018).

    Article  Google Scholar 

  11. Liu, Y., McGuire, J. J. & Behn, M. D. Aseismic transient slip on the Gofar transform fault, East Pacific Rise. Proc. Natl Acad. Sci. USA 117, 10188–10194 (2020).

    Article  Google Scholar 

  12. Kohli, A. H. & Warren, J. M. Evidence for a deep hydrologic cycle on oceanic transform faults. J. Geophys. Res. 125, B017751 (2020).

    Article  Google Scholar 

  13. Prigent, C., Warren, J. M., Kohli, A. H. & Teyssier, C. Fracture-mediated deep seawater flow and mantle hydration on oceanic transform faults. Earth Planet. Sci. Lett. 532, 115988 (2020).

    Article  Google Scholar 

  14. Connolly, J. A. D. The geodynamic equation of state: what and how. Geochem. Geophys. Geosyst. 10, Q10014 (2009).

    Article  Google Scholar 

  15. Guillot, S., Schwartz, S., Reynard, B., Agard, P. & Prigent, C. Tectonic significance of serpentinites. Tectonophysics 646, 1–19 (2015).

    Article  Google Scholar 

  16. Fumagalli, P., Zanchetta, S. & Poli, S. Alkali in phlogopite and amphibole and their effects on phase relations in metasomatized peridotites: a high-pressure study. Contrib. Mineral. Petrol. 158, 723–737 (2009).

    Article  Google Scholar 

  17. Chernosky, J. V. Jr, Berman, R. G. J. & Jenkins, D. M. The stability of tremolite: new experimental data and a thermodynamic assessment. Am. Mineral. 83, 726–738 (1998).

    Article  Google Scholar 

  18. Hirth, G. & Kohlstedt, D. in Inside the Subduction Factory (ed. Eiler, J.) 83–105 (AGU, 2003).

  19. Hansen, L. N., Zimmerman, M. E. & Kohlstedt, D. L. Grain boundary sliding in San Carlos olivine: flow law parameters and crystallographic-preferred orientation. J. Geophys. Res. 116, B08201 (2011).

    Google Scholar 

  20. Ohuchi, T. et al. Dislocation-accommodated grain boundary sliding as the major deformation mechanism of olivine in the Earth’s upper mantle. Sci. Adv. 1, e1500360 (2015).

    Article  Google Scholar 

  21. Carter, N. L. & Avé Lallemant, H. G. High temperature flow of dunite and peridotite. Geol. Soc. Am. Bull. 81, 2181–2202 (1970).

    Article  Google Scholar 

  22. Karato, S.-I., Paterson, M. & Fitzgerald, D. Rheology of synthetic olivine aggregates: Influence of grain size and water. J. Geophys. Res. 91, 8151–8176 (1986).

    Article  Google Scholar 

  23. Chopra, P. N. & Paterson, M. S. The experimental deformation of dunite. Tectonophysics 78, 453–473 (1981).

    Article  Google Scholar 

  24. Hirth, G. & Kohlstedt, D. L. Water in the oceanic upper mantle: implications for rheology, melt extraction and the evolution of the lithosphere. Earth Planet. Sci. Lett. 144, 93–108 (1996).

    Article  Google Scholar 

  25. Fusseis, F., Regenauer-Lieb, K., Liu, J., Hough, R. M. & De Carlo, F. Creep cavitation can establish a dynamic granular fluid pump in ductile shear zones. Nature 459, 974–977 (2009).

    Article  Google Scholar 

  26. Précigout, J., Prigent, C., Palasse, L. & Pochon, A. Water pumping in mantle shear zones. Nat. Commun. 8, 15736 (2017).

    Article  Google Scholar 

  27. Getsinger, A. J. & Hirth, G. Amphibole fabric formation during diffusion creep and the rheology of shear zones. Geology 42, 535–538 (2014).

    Article  Google Scholar 

  28. Tommasi, A., Langone, A., Padrón-Navarta, J. A., Zanetti, A. & Vauchez, A. Hydrous melts weaken the mantle, crystallization of pargasite and phlogopite does not: insights from a petrostructural study of the Finero peridotites, southern Alps. Earth Planet. Sci. Lett. 477, 59–72 (2017).

    Article  Google Scholar 

  29. Hilairet, N. et al. High-pressure creep of serpentine, interseismic deformation, and initiation of subduction. Science 318, 1910–1913 (2007).

    Article  Google Scholar 

  30. Platt, J. P. & Behr, W. M. Grain size evolution in ductile shear zones: implications for strain localization and the strength of the lithosphere. J. Struct. Geol. 33, 537–550 (2011).

    Article  Google Scholar 

  31. Reinen, L. A., Weeks, J. D. & Tullis, T. E. The frictional behavior of lizardite and antigorite serpentinites: experiments, constitutive models, and implications for natural faults. Pure Appl. Geophys. 143, 317–358 (1994).

    Article  Google Scholar 

  32. Moore, D. E., Lockner, D. A., Ma, S., Summers, R. & Byerlee, J. D. Strengths of serpentinite gouges at elevated temperatures. J. Geophys. Res. 102, 14787–14801 (1997).

    Article  Google Scholar 

  33. Moore, D. E. & Lockner, D. A. Frictional strengths of talc–serpentine and talc–quartz mixtures. J. Geophys. Res. 116, B01403 (2011).

    Google Scholar 

  34. Cannat, M., Bideau, D. & Hébert, R. Plastic deformation and magmatic impregnation in serpentinized ultramafic rocks from the Garrett transform fault (East Pacific Rise). Earth Planet. Sci. Lett. 101, 216–232 (1990).

    Article  Google Scholar 

  35. Constantin, M. Gabbroic intrusions and magmatic metasomatism in harzburgites from the Garrett transform fault: Implications for the nature of the mantle-crust transition at fast-spreading ridges. Contrib. Mineral. Petrol. 136, 111–130 (1999).

    Article  Google Scholar 

  36. Aderhold, K. & Abercrombie, R. E. The 2015 Mw 7.1 earthquake on the Charlie–Gibbs transform fault: repeating earthquakes and multimodal slip on a slow oceanic transform. Geophys. Res. Lett. 43, 6119–6128 (2016).

    Article  Google Scholar 

  37. Wolfson-Schwehr, M. & Boettcher, M. S. in Transform Plate Boundaries and Fracture Zones (ed. Duarte, J. C.) 21–59 (Elsevier, 2019).

  38. Moyer, P. A., Boettcher, M. S., McGuire, J. J. & Collins, J. A. Spatial and temporal variations in earthquake stress drop on Gofar Transform Fault, East Pacific Rise: implications for fault strength. J. Geophys. Res. 123, 7722–7740 (2018).

    Article  Google Scholar 

  39. Byerlee, J. Friction of rocks. Pure Appl. Geophys. 116, 615–626 (1978).

    Article  Google Scholar 

  40. Stein, C. A. & Stein, S. A model for the global variation in oceanic depth and heat flow with lithospheric age. Nature 359, 123–128 (1992).

    Article  Google Scholar 

  41. Behn, M. D., Boettcher, M. S. & Hirth, G. Thermal structure of oceanic transform faults. Geology 35, 307–310 (2007).

    Article  Google Scholar 

  42. Dalton, C. A., Langmuir, C. H. & Gale, A. Geophysical and geochemical evidence for deep temperature variations beneath mid-ocean ridges. Science 344, 80–83 (2014).

    Article  Google Scholar 

  43. Hartnady, C. J. H. & le Roex, A. P. Southern Ocean hotspot tracks and the Cenozoic absolute motion of the African, Antarctic, and South American plates. Earth Planet. Sci. Lett. 75, 245–257 (1985).

    Article  Google Scholar 

  44. Roland, E., Behn, M. D. & Hirth, G. Thermal-mechanical behavior of oceanic transform faults: implications for the spatial distribution of seismicity. Geochem. Geophys. Geosyst. 11, Q07001 (2010).

    Article  Google Scholar 

  45. Tasaka, M., Hiraga, T. & Zimmerman, M. E. Influence of mineral fraction on the rheological properties of forsterite + enstatite during grain-size-sensitive creep: 2. Deformation experiments.J. Geophys. Res. 118, 3991–4012 (2013).

    Article  Google Scholar 

  46. Sibson, R. H. Frictional constraints on thrust, wrench and normal faults. Nature 249, 542–544 (1974).

    Article  Google Scholar 

  47. Beeler, N. M., Hirth, G., Thomas, A. & Bürgmann, R. Effective stress, friction, and deep crustal faulting. J. Geophys. Res. 121, 1040–1059 (2015).

    Article  Google Scholar 

  48. Kohli, A. H. & Warren, J. M. X-ray diffraction data on peridotite mylonites from the Shaka Transform Fault, Southwest Indian Ridge, Version 1.0 (Interdisciplinary Earth Data Alliance, accessed 13 August 2019); https://doi.org/10.1594/IEDA/111356

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Acknowledgements

We thank C. Teyssier, S. Birner, K. Kumamoto, L. Hansen, M. Boettcher, M. Behn, J. McGuire and G. Hirth for helpful discussions. This work was supported by a NSF Graduate Research Fellowship to A.K. and NSF grants EAR-1347696, EAR-1619880 and OCE-1832868 to J.M.W.

Author information

Authors and Affiliations

  1. Department of Geophysics, Stanford University, Stanford, CA, USA

    Arjun Kohli

  2. Center for Coastal and Ocean Mapping, University of New Hampshire, Durham, NH, USA

    Monica Wolfson-Schwehr

  3. Institut de Physique du Globe de Paris, Université de Paris, CNRS, Paris, France

    Cécile Prigent

  4. Department of Earth Sciences, University of Delaware, Newark, DE, USA

    Jessica M. Warren

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Contributions

A.K., C.P. and J.M.W. performed analyses of the mylonite samples. M.W.-S. built the thermal models. C.P. conducted the geochemical measurements. A.K. performed the rheology calculations. All the authors discussed the results and contributed to writing the manuscript.

Corresponding authors

Correspondence to Arjun Kohli or Jessica M. Warren.

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The authors declare no competing interests.

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Peer review information Nature Geosciences thanks the anonymous reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Stefan Lachowycz.

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Extended data

Extended Data Fig. 1 Deformation mechanism maps for Shaka transform fault.

Maps were generated using the flow law parameters in Extended Data Table 2. a, Protolith. b, HT mylonite. c, MT mylonite. d, LT mylonite.

Extended Data Fig. 2 Deformation mechanism maps for Gofar transform fault.

Maps were generated using the flow law parameters in Extended Data Table 2. a, Protolith. b, HT mylonite. c, MT mylonite. d, LT mylonite.

Extended Data Fig. 3 Composite deformation mechanism maps for (a) Shaka and (b) Gofar transform faults.

The total strain rate is the arithmetic sum of the strain rates from each deformation mechanism (that is, Ol total in Extended Data Figs. 1, 2). The ranges for each curve represent uncertainty in the pressure-temperature estimates for deformation.

Extended Data Fig. 4 Modified friction-effective stress relationship for olivine and serpentine.

Modified friction-effective stress relationship for (a) olivine and (b) serpentine calculated using the Shaka geotherm (Fig. 2a) and hydrostatic pore fluid pressure (λ=0.4). The pore fluid factor, α, decreases from 1 at the surface to 0 at the brittle-ductile transition as the normal stress on asperity contacts nears the yield strength.

Extended Data Table 1 Material properties and boundary conditions for fault thermal models (Fig. 2a,b)
Full size table
Extended Data Table 2 Flow laws and constitutive parameters used in deformation mechanism maps (Extended Data Figs. 1, 2) and strength-depth profiles (Fig. 3). *The value of A has been adjusted from the original references to account for revised estimates of the water content in the experimental samples. GBS - Grain boundary sliding; LTP - Low temperature plasticity
Full size table

Supplementary information

Supplementary Information

Supplementary Fig. 1, discussion and Tables 1–4.

Source data

Source Data Fig. 1a

Oceanic transform fault locations, lengths, and slip rates.

Source Data Fig. 1e

Mineral chlorine concentrations in SWIR mylonites.

Source Data Fig. 2c

Calcium in orthopyroxene thermometry data.

Source Data Fig. 3b

Earthquake times, locations, and magnitudes from the 2008 Gofar OBS deployment.

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Kohli, A., Wolfson-Schwehr, M., Prigent, C. et al. Oceanic transform fault seismicity and slip mode influenced by seawater infiltration. Nat. Geosci. 14, 606–611 (2021). https://doi.org/10.1038/s41561-021-00778-1

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