Experimental demonstration of a semi-brittle origin for crustal strain transients

Abstract

Tectonic motions give rise to destructive earthquakes and transient slip events. These movements are often described by friction laws for stick–slip motion on brittle fault surfaces and gouge-filled zones1,2. Yet, many transient slip events, such as slow earthquakes and aseismic creep, occur in rocks that exhibit mixed brittle–ductile rheology, where these friction laws are not clearly applicable3,4. Here we describe the flow and evolution of fractures as observed in a semi-brittle rock analogue exposed to shear stress in laboratory experiments. We find that, depending on the strength of the rock-analogue material, and thus the magnitude of yield stress, the material exhibits either creep-like or stick–slip behaviour. At low yield stress, deformation occurs as constant creep along a main fracture, whereas at high yield stress, the material exhibits stick–slip behaviour. However, the deformation does not involve frictional behaviour; it is instead accommodated by the initiation and growth of a system of tensional and shear fractures. The opening and interplay of such fracture systems could generate tectonic tremor and slow slip. Our laboratory experiments thus support a frictionless alternative mechanism for the development of tectonic strain transients.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Sketch and corresponding photomicrographs illustrating the micromechanical deformation of thin layer of Carbopol (Ultrez 10, 2 wt%).
Figure 2: Force and displacement versus time of brittle, semi-brittle and viscous experiments.
Figure 3: Overview of brittle (top row) to ductile deformation (bottom row) with two styles of semi-brittle deformation (middle rows).

References

  1. 1

    Scholz, C. H. Earthquakes and friction laws. Nature 391, 37–42 (1998).

    Article  Google Scholar 

  2. 2

    Dieterich, J. H. Time-dependent friction and mechanics of stick-slip. Pure Appl. Geophys. 116, 790–806 (1978).

    Article  Google Scholar 

  3. 3

    Mancktelow, N. S. & Pennacchioni, G. The control of precursor brittle fracture and fluid-rock interaction on the development of single and paired ductile shear zones. J. Struct. Geol. 27, 645–661 (2005).

    Article  Google Scholar 

  4. 4

    Segall, P. & Simpson, C. Nucleation of ductile shear zones on dilatant fractures. Geology 14, 56–59 (1986).

    Article  Google Scholar 

  5. 5

    Pec, M., Stunitz, H. & Heilbronner, R. Semi-brittle deformation of granitoid gouges in shear experiments at elevated pressures and temperatures. J. Struct. Geol. 38, 200–221 (2012).

    Article  Google Scholar 

  6. 6

    Handy, M. R. The solid-state flow law of polymineralic rocks. J. Geophys. Res. 95, 8647–8661 (1990).

    Article  Google Scholar 

  7. 7

    Lavier, L. L., Bennett, R. A. & Duddu, R. Creep events at the brittle ductile transition. Geochem. Geophys. Geosyst. 14, 3334–3351 (2013).

    Article  Google Scholar 

  8. 8

    Fusseis, F. & Handy, M. R. Micromechanisms of shear zone propagation at the brittle-viscous transition. J. Struct. Geol. 30, 1242–1253 (2008).

    Article  Google Scholar 

  9. 9

    Hayman, N. W. & Lavier, L. L. The geologic record of deep episodic tremor and slip. Geology 42, 195–198 (2014).

    Article  Google Scholar 

  10. 10

    Reber, J. E., Hayman, N. W. & Lavier, L. L. Stick-slip and creep behavior in lubricated granular material: Insights into the brittle–ductile transition. Geophys. Res. Lett. 41, 3471–3477 (2014).

    Article  Google Scholar 

  11. 11

    Fagereng, A. & Harris, C. Interplay between fluid flow and fault-fracture mesh generation within underthrust sediments: Geochemical evidence from the Chrystalls Beach Complex, New Zealand. Tectonophysics 612, 147–157 (2014).

    Article  Google Scholar 

  12. 12

    Wech, A. G. & Creager, K. C. A continuum of stress, strength and slip in the Cascadia subduction zone. Nature Geosci. 4, 624–628 (2011).

    Article  Google Scholar 

  13. 13

    Dresen, G. & Evans, B. Brittle and semibrittle deformation of synthetic marbles composed of 2 phases. J. Geophys. Res. 98, 11921–11933 (1993).

    Article  Google Scholar 

  14. 14

    Technical Data Sheets for Carbopol (Lubrizol, 2014); https://www.lubrizol.com/PersonalCare/Products/Carbopol/Ultrez10.html

  15. 15

    Kim, J., Song, J., Lee, E. & Park, S. Rheological properties and microstructures of Carbopol gel network system. Colloid Polym. Sci. 281, 614–623 (2003).

    Article  Google Scholar 

  16. 16

    Piau, J. M. Carbopol gels: Elastoviscoplastic and slippery glasses made of individual swollen sponges: Meso- and macroscopic properties, constitutive equations and scaling laws. J. Non-Newton. Fluid Mech. 144, 1–29 (2007).

    Article  Google Scholar 

  17. 17

    Tiu, C., Guo, J. & Uhlherr, P. H. T. Yielding, behaviour of viscoplastic materials. J. Ind. Eng. Chem. 12, 653–662 (2006).

    Google Scholar 

  18. 18

    Divoux, T., Barentin, C. & Manneville, S. From stress-induced fluidization processes to Herschel–Bulkley behaviour in simple yield stress fluids. Soft Matter 7, 8409–8418 (2011).

    Article  Google Scholar 

  19. 19

    Daniels, K. E. & Hayman, N. W. Force chains in seismogenic faults visualized with photoelastic granular shear experiments. J. Geophys. Res. 113, B11411 (2008).

    Article  Google Scholar 

  20. 20

    Herrmann, H. J., Hovi, J.-P. & Luding, S. Physics of Dry Granular Media (Springer, 1997).

    Google Scholar 

  21. 21

    Beach, A. Geometry of en-echelon vein arrays. Tectonophysics 28, 245–263 (1975).

    Article  Google Scholar 

  22. 22

    Ramsay, J. G. & Huber, M. I. The Techniques of Modern Structural Geology Vol. 2 (Academic Press, 1987).

    Google Scholar 

  23. 23

    Grasemann, B. & Stuwe, K. The development of flanking folds during simple shear and their use as kinematic indicators. J. Struct. Geol. 23, 715–724 (2001).

    Article  Google Scholar 

  24. 24

    Griffith, W. A., Sanz, P. F. & Pollard, D. D. Influence of outcrop scale fractures on the effective stiffness of fault damage zone rocks. Pure Appl. Geophys. 166, 1595–1627 (2009).

    Article  Google Scholar 

  25. 25

    Rybacki, E., Wirth, R. & Dresen, G. Superplasticity and ductile fracture of synthetic feldspar deformed to large strain. J. Geophys. Res. 115, B08209 (2010).

    Article  Google Scholar 

  26. 26

    Cox, S. J. D. & Scholz, C. H. On the formation and growth of faults—An experimental-study. J. Struct. Geol. 10, 413–430 (1988).

    Article  Google Scholar 

  27. 27

    Pollard, D. D., Segall, P. & Delaney, P. T. Formation and interpretation of dilatant echelon cracks. Geol. Soc. Am. Bull. 93, 1291–1303 (1982).

    Article  Google Scholar 

  28. 28

    Ide, S., Beroza, G. C., Shelly, D. R. & Uchide, T. A scaling law for slow earthquakes. Nature 447, 76–79 (2007).

    Article  Google Scholar 

  29. 29

    Abad, I., Mata, M. P., Nieto, F. & Velilla, N. The phyllosilicates in diagenetic-metamorphic rocks of the South Portuguese Zone, southwestern Portugal. Can. Mineral. 39, 1571–1589 (2001).

    Article  Google Scholar 

  30. 30

    Carreras, J. Zooming on Northern Cap de Creus shear zones. J. Struct. Geol. 23, 1457–1486 (2001).

    Article  Google Scholar 

  31. 31

    Benmouffok-Benbelkacem, G., Caton, F., Baravian, C. & Skali-Lami, S. Non-linear viscoelasticity and temporal behavior of typical yield stress fluids: Carbopol, Xanthan and Ketchup. Rheol. Acta 49, 305–314 (2010).

    Article  Google Scholar 

  32. 32

    Odonne, F. & Vialon, P. Analog models of folds above a wrench fault. Tectonophysics 99, 31–46 (1983).

    Article  Google Scholar 

  33. 33

    Di Giuseppe, E. et al. Characterization of Carbopol hydrogel rheology for experimental tectonics and geodynamics. Tectonophysics 642, 29–45 (2014).

    Article  Google Scholar 

  34. 34

    Schrank, C. E., Boutelier, D. A. & Cruden, A. R. The analogue shear zone: From rheology to associated geometry. J. Struct. Geol. 30, 177–193 (2008).

    Article  Google Scholar 

  35. 35

    Coussot, P., Tocquer, L., Lanos, C. & Ovarlez, G. Macroscopic vs. local rheology of yield stress fluids. J. Non-Newton. Fluid Mech. 158, 85–90 (2009).

    Article  Google Scholar 

  36. 36

    Weijermars, R. Finite strain of laminar flows can be visualized in SGM36-Polymer. Naturwissenschaften 73, 33–34 (1986).

    Article  Google Scholar 

  37. 37

    Weijermars, R. Flow behaviour and physical chemistry of bouncing putties and related polymers in view of tectonic laboratory applications. Tectonophysics 124, 325–358 (1986).

    Article  Google Scholar 

Download references

Acknowledgements

Financial support for the project came from UTIG and Petrobras. This is UTIG paper number 2850.

Author information

Affiliations

Authors

Contributions

J.E.R. performed the experiments and contributed to the data interpretation and preparation of the manuscript. L.L.L. provided the theoretical motivation for the experiments and contributed to the data interpretation and preparation of the manuscript. N.W.H. contributed to the data interpretation and preparation of the manuscript.

Corresponding author

Correspondence to Jacqueline E. Reber.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 1109 kb)

41561_2015_BFngeo2496_MOESM291_ESM.wmv

Supplementary Information (WMV 3805 kb)

Supplementary Information

Supplementary Information (WMV 3805 kb)

41561_2015_BFngeo2496_MOESM292_ESM.wmv

Supplementary Information (WMV 8607 kb)

Supplementary Information

Supplementary Information (WMV 8607 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Reber, J., Lavier, L. & Hayman, N. Experimental demonstration of a semi-brittle origin for crustal strain transients. Nature Geosci 8, 712–715 (2015). https://doi.org/10.1038/ngeo2496

Download citation

Further reading