Abstract
The shear strength of fault gouge plays an important role in the dynamic behavior of faults, ranging from small-scale displacements to severe earthquakes. The characteristics and interactions of constituent materials in fault gouge are the main determinants of shear strength. Assessing the shear strength of fault gouge by means of experiments, however, requires time-consuming procedures, including sampling, shear testing, and reliability checking; consequently, simple and indirect methods to assess shear strength in terms of the characteristics of fault gouge fragments have been investigated. This study focuses on the influence of the shape of fault gouge particles on the shear strength of gouge. We introduce a novel technique to obtain shape parameters of particles using Xray computed tomography (CT), and then show the effects of particle shape on the friction angle of the fault gouge. Samples collected from fault zones developed in various parent rock materials were tested in laboratory experiments to characterize their shear strengths. After shear testing, the particles in the fault gouge were collected, scanned by X-ray CT, and then analyzed for shape characterization. We successfully determined the shape parameters (sphericity, elongation, flatness, and slenderness) of the fault gouge fragments, and found that the parameters are well correlated with the friction angle of the gouge.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abe, S. and Mair, K., 2009, Effects of gouge fragment shape on fault friction: New 3D modelling results. Geophysical Research Letters, 36, L23302.
An, L.J. and Sammis, C.G., 1994, Particle size distribution of cataclastic fault materials from southern California A 3-D study. Pure and Applied Geophysics, 143, 203–227.
Anochie-Boateng, J.K., Komba, J.J., and Mvelase, G.M., 2013, Three-dimensional laser scanning technique to quantify aggregate and ballast shape properties. Construction and Building Materials, 43, 389–398.
Billi, A., Salvini, F., and Storti, F., 2003, The damage zone-fault core transition in carbonate rocks: implications for fault growth, structure and permeability. Journal of Structural Geology, 25, 1779–1794.
Blenkinsop, T.G., 1991, Cataclasis and processes of particle size reduction. Pageoph, 136, 59–86.
Chester, F.M. and Logan, J.M., 1986, Implications for mechanical properties of brittle faults from observations of the Punchbowl fault zone, California. Pure and Applied Geophysics, 124, 79–106.
Engelder, J.T., 1974, Cataclasis and the generation of fault gouge. Geological Society of America Bulletin, 85, 1515–1522.
Evans, J.P., Forster, C.B., and Goddard, J.V., 1997, Permeability of fault-related rocks, and implications for hydraulic structure of fault zones. Journal of Structural Geology, 19, 1393–1404.
Garboczi, E.J., 2011, Three dimensional shape analysis of JSC-1A simulated lunar regolith particles. Powder Technology, 207, 96–103.
Gundlach, B. and Blum, J., 2013, A new method to determine the grain size of planetary regolith. Icarus, 223, 479–492.
Haines, S.H., Kaproth, B., Marone, C., Saffer, D., and van der Pluijm, B., 2013, Shear zones in clay-rich fault gouge: A laboratory study of fabric development and evolution. Journal of Structural Geology, 51, 206–225.
Heilbronner, R. and Keulen, N., 2006, Grain size and grain shape analysis of fault rocks. Tectonophysics, 427, 199–216.
Hu, J. and Stroeven, P., 2006, Shape characterization of concrete aggregate. Image analysis and stereology, 25, 43–53.
Lehmann, G. and Legland, D., 2012, Efficient N-Dimensional surface estimation using Crofton formula and run-length encoding. Insight Journal, 1–11.
Liao, L., Meneghini, R., Nowell, H.K., and Liu, G., 2013, Scattering computations of snow aggregates from simple geometrical particle models. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 6, 1409–1417.
Lin, A., 1999, Roundness of clasts in pseudotachylytes and cataclastic rocks as an indicator of frictinal melting. Journal of Structural Geology, 21, 473–478.
Liu, Q., Button, E., and Klima, K., 2007, Investigation for probabilistic prediction of shear strength properties of clay-rich fault gouge in the Austrian Alps. Engineering Geology, 94, 103–121.
Lockner, D.A., Morrow, C., Moore, D., and Hickman, S., 2011, Low strength of deep San Andreas fault gouge from SAFOD core. Nature, 472, 82–85.
Mair, K. and Abe, S., 2008, 3D numerical simulations of fault gouge evolution during shear: Grain size reduction and strain localization. Earth and Planetary Science Letters, 274, 72–81.
Mair, K. and Abe, S., 2011, Breaking up: comminution mechanisms in sheared simulated fault gouge. Pure and Applied Geophysics, 168, 2277–2288.
Mora, P. and Place, D., 1998, Numerical simulation of earthquake faults with gouge: Toward a comprehensive explanation for the heat flow paradox. Journal of Geophysical Research, 103, 21067.
Morrow, C.A., Moore, D.E., and Lockner, D.A., 2000, The effect of mineral bond strength and adsorbed water on fault gouge frictional strength. Geophysical Research Letters, 27, 815–818.
Rong, G., Liu, G., Hou, D., and Zhou, C.B., 2013, Effect of particle shape on mechanical behaviors of rocks: a numerical study using clumped particle model. Scientific World Journal, 2013, 589215.
Roussillon, T., Piégay, H., Sivignon, I., Tougne, L., and Lavigne, F., 2009, Automatic computation of pebble roundness using digital imagery and discrete geometry. Computers & Geosciences, 35, 1992–2000.
Rutter, E.H., Maddock, R.H., Hall, S.H., and White, S.H., 1986, Comparative microstructures of natural and experimentally produced clay-bearing fault gouges. Pure and Applied Geophysics, 124, 3–30.
Sausgruber, T. and Brandner, R., 2001, The relevance of brittle fault zones in tunnel construction- Lower inn valley feeder line north of the Brenner base tunnel, Tyrol, Austria. Österreichische Geologische Gesellschaft-Band, 94, 157–172.
Storti, F., Billi, A., and Salvini, F., 2003, Particle size distributions in natural carbonate fault rocks. Earth and Planetary Science Letters, 206, 173–186.
Streit, J.E., 1997, Low frictional strength of upper crustal faults: A model. Journal of Geophysical Research, 10, 24619.
Sulem, J., Vardoulakis, I., Ouffroukh, H., Boulon, M., and Hans, J., 2004, Experimental characterization of the thermo-poro-mechanical properties of the Aegion Fault gouge. Comptes Rendus Geoscience, 336, 455–466.
Wadell, H., 1932, Volume, shape, and roundness of rock particles. Journal of Geology, 40, 443–451.
Wallace, R.E. and Morris, H.T., 1986, Characteristics of faults and shear zones in deep mines. Pure and Applied Geophysics, 124, 107–125.
Wu, F.T., Blatter, L., and Roberson, H., 1975, Clay gouges in the san andreas fault system and their possible implications. Pure and Applied Geophysics, 113, 87–95.
Zingg, S. and Anagnostou, G., 2012, Tunnel face stability in narrow water-bearing fault zones. ISRM International Symposium, Eurock 2012, Stockholm, 1–11.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kim, K.Y., Suh, H.S., Yun, T.S. et al. Effect of particle shape on the shear strength of fault gouge. Geosci J 20, 351–359 (2016). https://doi.org/10.1007/s12303-015-0051-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12303-015-0051-0