Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
F. J. Cooper; J. P. Platt; W. M. Behr (2017)
Publisher: Copernicus Publications
Journal: Solid Earth
Languages: English
Types: Article
Subjects: Petrology, Q, QE500-639.5, Dynamic and structural geology, QE640-699, Science, QE1-996.5, Geology, Stratigraphy, QE420-499

High-strain mylonitic rocks in Cordilleran metamorphic core complexes reflect ductile deformation in the middle crust, but in many examples it is unclear how these mylonites relate to the brittle detachments that overlie them. Field observations, microstructural analyses, and thermobarometric data from the footwalls of three metamorphic core complexes in the Basin and Range Province, USA (the Whipple Mountains, California; the northern Snake Range, Nevada; and Ruby Mountains-East Humboldt Range, Nevada), suggest the presence of two distinct rheological transitions in the middle crust: (1) the brittle-ductile transition (BDT), which depends on thermal gradient and tectonic regime, and marks the switch from discrete brittle faulting and cataclasis to continuous, but still localized, ductile shear, and (2) the localized-distributed transition, or LDT, a deeper, dominantly temperature-dependent transition, which marks the switch from localized ductile shear to distributed ductile flow. In this model, brittle normal faults in the upper crust persist as ductile shear zones below the BDT in the middle crust, and sole into the subhorizontal LDT at greater depths.

In metamorphic core complexes, the presence of these two distinct rheological transitions results in the development of two zones of ductile deformation: a relatively narrow zone of high-stress mylonite that is spatially and genetically related to the brittle detachment, underlain by a broader zone of high-strain, relatively low-stress rock that formed in the middle crust below the LDT, and in some cases before the detachment was initiated. The two zones show distinct microstructural assemblages, reflecting different conditions of temperature and stress during deformation, and contain superposed sequences of microstructures reflecting progressive exhumation, cooling, and strain localization. The LDT is not always exhumed, or it may be obscured by later deformation, but in the Whipple Mountains, it can be directly observed where high-strain mylonites captured from the middle crust depart from the brittle detachment along a mylonitic front.

  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • 6 Anderson, J. L. and Rowley, M.: Synkinematic intrusion of peraluminous and associated metaluminous granitic magmas, Whipple Mountains, California, Canadian Mineralogist, 19 pp., 1981.
    • Anderson, J. L., Barth, A. P., and Young, E. D.: Mid-crustal Cretaceous roots of Cordilleran Metamorphic Core Complexes, Geology, 16, 366-369, 1988.
    • Axen, G. J. and Selverstone, J.: Stress state and fluid-pressure level along the Whipple detachment fault, California, Geology, 22, 835-838, 1994.
    • Bartley, J. M. and Wernicke, B. P.: The Snake Range decollement interpreted as a major extensional shear zone, Tectonics, 3, 647- 657, 1984.
    • Behr, W. M. and Platt, J. P.: A naturally constrained stress profile through the middle crust in an extensional terrane, Earth Planet. Sc. Lett., 303, 181-192, 2011.
    • Behr, W. M. and Platt, J. P.: Kinematic and thermal evolution during two-stage exhumation of a Mediterranean subduction complex, Tectonics, 31, TC4025, doi:10.1029/2012TC003121, 2012.
    • Behr, W. M. and Platt, J. P.: Rhelogical evolution of a Mediterranean subduction complex, J. Struct. Geol., 54, 136-155, doi:10.1016/j.jsg.2013.07.012, 2013.
    • Behr, W. M. and Platt, J. P.: Brittle faults are weak, yet the ductile middle crust is strong: Implications for lithospheric mechanics, Geophys. Res. Lett., 41, 8067-8075, 2014.
    • Behrmann, J. H.: Crystal plasticity and superplasticity in quartzite: a natural example, Tectonophysics, 115, 101-129, 1985.
    • Block, L. and Royden, L. H.: Core complex geometries and regional scale flow in the lower crust, Tectonics, 9, 557-567, 1990.
    • Brown, R. L. and Murray Journeay, J.: Tectonic denudation of the Shuswap metamorphic terrane of southeastern British Columbia, Geology, 15, 142-146, 1987.
    • Carpenter, B. M., Saffer, D. M., and Marone, C.: Frictional properties and sliding stability of the San Andreas fault from deep drill core, Geology, 40, 759-762, 2012.
    • Colgan, J. P., Howard, K. A., Fleck, R. J., and Wooden, J. L.: Rapid middle Miocene extension and unroofing of the southern Ruby Mountains, Nevada, Tectonics, 29, TC6022, doi:10.1029/2009TC002655, 2010.
    • Collettini, C., Niemeijer, A., Viti, C., and Marone, C.: Fault zone fabric and fault weakness, Nature, 462, 907-910, 2009.
    • Coney, P. J.: Structural analysis of the Snake Range “decollement”, East-Central Nevada, Geol. Soc. Am. Bull., 85, 973-978, 1974.
    • Coney, P. J.: Cordilleran metamorphic core complexes, an overview, Geol. Soc. Am. Mem., 153, 7-31, 1980.
    • Cooper, F. J., Platt, J. P., Anczkiewicz, R., and Whitehouse, M. J.: Footwall dip of a core complex detachment fault: thermobarometric constraints from the northern Snake Range (Basin and Range, USA), J. Metamorph. Geol., 28, 997-1020, doi:10.1111/j.1525-1314.2010.00907.x, 2010a.
    • Cooper, F. J., Platt, J. P., Platzman, E. S., Grove, M. J., and Seward, G.: Opposing shear senses in a subdetachment mylonite zone: Implications for core complex mechanics, Tectonics, 29, TC4019, doi:10.1029/2009TC002632, 2010b.
    • Crafford, A. E. J.: Geologic map of Nevada, US Geological Survey Data Series 249, 46 pp., 2007.
    • Davis, G. A.: Rapid upward transport of mid-crustal mylonitic gneisses in the footwall of a Miocene detachment fault, Whipple Mountains, southeastern California, Geol. Rundsch., 77, 191- 209, 1988.
    • Davis, G. A. and Lister, G. S.: Detachment faulting in continental extension, perspectives from the southwestern US Cordillera, Geol. S. Am. S., 218, 133-159, 1988.
    • Davis, G. A., Anderson, J. L., Frost, E. G., and Shackelford, T. J.: Mylonitization and detachment faulting in the WhippleBuckskin-Rawhide Mountains terrane, southeastern California and western Arizona, Geol. Soc. Am. Mem., 153, 79-129, 1980.
    • Davis, G. A., Lister, G. S., and Reynolds, S. J.: Structural evolution of the Whipple and South Mountain shear zones, southwestern United States, Geology, 14, 7-10, 1986.
    • DiToro, G., Hirose, T., Nielsen, S., Pennacchioni, G., and Shimamoto, T.: Natural and experimental evidence of melt lubrication of faults during earthquakes, Science, 311, 647-649, doi:10.1126/science.1121012, 2006.
    • Foster, D. A. and John, B. E.: Quantifying tectonic exhumation in an extensional orogen with thermochronology: examples from the southern Basin and Range Province, Geological Society of London Special Publication, 154, 343-364, doi:10.1144/GSL.SP.1999.154.01.16, 1999.
    • Gans, P. B. and Miller, E. L.: Style of mid-Tertiary extension in eastcentral Nevada, in: Geologic Excursions in the Overthrust Belt and Metamorphic Core Complexes of the Intermountain Region, edited by: Gurgel, K. D., Utah Geological and Mineral Survey Special Studies, Salt Lake City, Utah, 1983.
    • Gans, P. B., Miller, E. L., Huggins, C. C., and Lee, J.: Geologic map of the Little Horse Canyon Quadrangle, Nevada and Utah, Field Studies Map 20, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999a.
    • Gans, P. B., Miller, E. L., and Lee, J.: Geologic map of the Spring Mountain Quadrangle, Nevada and Utah, Field Studies Map 18, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999b.
    • Gaudemer, Y. and Tapponnier, P.: Ductile and brittle deformations in the northern Snake Range, Nevada, J. Struct. Geol., 9-2, 159- 180, 1987.
    • Gébelin, A., Mulch, A., Teyssier, C., Heizler, M., Vennemann, T., and Seaton, N. C. A.: Oligo-Miocene extensional tectonics and fluid flow across the Northern Snake Range detachment system, Nevada, Tectonics, 30, TC5010, doi:10.1029/2010TC002797, 2011.
    • Gébelin, A., Teyssier, C., Heizler, M., and Mulch, A.: Meteoric water circulation in a rolling-hinge detachment system (northern Snake Range core complex, Nevada), GSA Bulletin, 127, 149- 161, doi:10.1130/B31063.1, 2015.
    • Grasemann, B. and Dabrowski, M.: Winged inclusions: Pinch-andswell objects during high-strain simple shear, J. Struct. Geol., 70, 78-94, 2015.
    • Gross, C. E.: Tectonic significance of mylonites in the little Buckskin Mountains, west-central Arizona: Insights from quartz microstructural data, Vancouver, Canada, 2014.
    • Hacker, B. R., Yin, A., Christie, J. M., and Davis, G. A.: Stress magnitude, strain rate, and rheology of extended middle continental crust inferred from quartz grain sizes in the Whipple Mountains, California, Tectonics, 11, 36-46, 1992.
    • Haines, S. H. and van der Pluijm, B. A.: Clay quantification and Ar-Ar dating of synthetic and natural gouge: Application to the Miocene Sierra Mazatán detachment fault, Sonora, Mexico, J. Struct. Geol., 30, 525-538, 2008.
    • Haines, S. H. and van der Pluijm, B. A.: Patterns of mineral transformations in clay gouge, with examples from low-angle normal fault rocks in the western USA, J. Struct. Geol., 43, 2-32, 2012.
    • Hallett, B. W. and Spear, F. S.: The P-T History of Anatectic Pelites of the Northern East Humboldt Range, Nevada: Evidence for Tectonic Loading, Decompression, and Anatexis, J. Petrol., 55, 3-36, doi:10.1093/petrology/egt057, 2014.
    • Handy, M. R.: Flow laws for rocks containing two non-linear viscous phases: a phenomenological approach, J. Struct. Geol., 16, 287-301, 1994.
    • Henry, C. D., McGrew, A. J., Colgan, J. P., Snoke, A. W., and Brueseke, M. E.: Timing, distribution, amount, and style of Cenozoic extension in the northern Great Basin, Geologic Field Trips to the Basin and Range, Rocky Mountains, Snake River Plain, and Terranes of the US Cordillera, Geological Society of America Field Guide, 21, 27-66, 2011.
    • Hirth, G. and Beeler, N. M.: The role of fluid pressure on frictional behavior at the base of the seismogenic zone, Geology, 43, 223- 226, doi:10.1130/G36361.1, 2015.
    • Hirth, G. and Kohlstedt, D.: Rheology of the Upper Mantle and the Mantle Wedge: A View from the Experimentalists, Inside the Subduction Factory, 83-105, doi:10.1029/138GM06, 2003.
    • Hirth, G. and Tullis, J.: Dislocation creep regimes in quartz aggregates, J. Struct. Geol., 14, 145-160, 1992.
    • Hirth, G., Teyssier, C., and Dunlap, W. J.: An evaluation of quartzite flow laws based on comparisons between experimentally and naturally deformed rocks, Int. J. Earth Sci., 90, 77-87, 2001.
    • Holdsworth, R. E., Van Diggelen, E. W. E., Spiers, C. J., De Bresser, J. H. P., Walker, R. J., and Bowen, L.: Fault rocks from the SAFOD core samples: Implications for weakening at shallow depths along the San Andreas Fault, California, J. Struct. Geol., 33, 132-144, doi:10.1016/j.jsg.2010.11.010, 2011.
    • Holyoke, C. W. and Kronenberg, A. K.: Accurate differential stress measurement using the molten salt cell and solid salt assemblies in the Griggs apparatus with applications to strength, piezometers and rheology, Tectonophysics, 494, 17-31, 2010.
    • Hose, R. K., Blake, M. C., and Smith, R. M.: Geology and mineral resources of White Pine County, Nevada, Nevada Bureau of Mines and Geology, Reno, Nevada, 1976.
    • John, B. E. and Mukasa, S. B.: Footwall rocks to the Mid-Tertiary Chemehuevi Detachment Fault: A window into the middle crust in the Southern Cordillera, J. Geophys. Res.-Sol. Ea., 95, 463- 485, doi:10.1029/JB095iB01p00463, 1990.
    • Lee, J.: Rapid uplift and rotation of mylonitic rocks from beneath a detachment fault: Insights from potassium feldspar 40Ar = 39Ar thermochronoloy, northern Snake Range, Nevada, Tectonics, 14, 54-77, 1995.
    • Lee, J. and Sutter, J. F.: Incremental 40Ar = 39Ar thermochronology of mylonitic rocks from the northern Snake Range, Nevada, Tectonics, 10, 77-100, 1991.
    • Lee, J., Miller, E. L., and Sutter, J. F.: Ductile strain and metamorphism in an extensional tectonic setting: A case study from the northern Snake Range, Nevada, USA, in: Continental Extensional Tectonics, edited by: Coward, M. P., Geological Society Special Publication, 1987.
    • Lee, J., Gans, P. B., and Miller, E. L.: Geologic map of the Mormon Jack Pass Quadrangle, Nevada, Field Studies Map 17, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999a.
    • Lee, J., Gans, P. B., and Miller, E. L.: Geologic map of the Third Butte East Quadrangle, Nevada, Field Studies Map 16, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999b.
    • Lee, J., Miller, E. L., Gans, P. B., and Huggins, C. C.: Geologic map of the Mount Moriah Quadrangle, Nevada, Field Studies Map 19, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999c.
    • Lewis, C. J., Wernicke, B. P., Selverstone, J., and Bartley, J. M.: Deep burial of the footwall of the northern Snake Range decollement, Nevada, Geol. Soc. Am. Bull., 111, 39-51, 1999.
    • Lister, G. S. and Snoke, A. W.: S-C Mylonites, J. Struct. Geol., 6, 617-638, 1984.
    • Lockner, D. A., Morrow, C., Moore, D., and Hickman, S.: Low strength of deep San Andreas fault gouge from SAFOD core, Nature, 472, 82-85, 2011.
    • Lovera, O. M., Heizler, M. T., and Harrison, T. M.: Argon diffusion domains in K-feldspar II: Kinetic properties of MH-10, Contrib. Mineral. Petr., 113, 381-393, 1993.
    • Lush, A. P., McGrew, A. J., Snoke, A. W., and Wright, J. E.: Allochthonous Archean basement in the northern East Humboldt Range, Nevada, Geology, 16, 349-353, 1988.
    • Luther, A., Axen, G., and Selverstone, J.: Particle-size distributions of low-angle normal fault breccias: Implications for slip mechanisms on weak faults, J. Struct. Geol., 55, 50-61, doi:10.1016/j.jsg.2013.07.009, 2013.
    • MacCready, T., Snoke, A. W., Wright, J. E., and Howard, K. A.: Mid-crustal flow during Tertiary extension in the Ruby Mountains core complex, Nevada, Geol. Soc. Am. Bull., 109, 1576- 1594, 1997.
    • McGrew, A. J. and Snee, L. W.: 40Ar = 39Ar thermochronologic constraints on the tectonothermal evolution of the northern East Humboldt Range metamorphic core complex, Nevada, Tectonophysics, 238, 425-450, 1994.
    • McGrew, A. J., Peters, M. T., and Wright, J. E.: Thermobarometric constraints on the tectonothermal evolution of the East Humboldt Range metamorphic core complex, Nevada, Geol. Soc. Am. Bull., 112, 45-60, 2000.
    • McKenzie, D. and Jackson, J. A.: Conditions for flow in the continental crust, Tectonics, 21, TC1055, doi:10.1029/2002TC001394, 2002.
    • McKenzie, D., Nimmo, F., Jackson, J. A., Gans, P. B., and Miller, E. L.: Characteristics and consequences of flow in the lower crust, J. Geophys. Res., 105, 11029-11046, 2000.
    • Miller, E. L. and Gans, P. B.: Cretaceous crustal structure and metamorphism in the hinterland of the Sevier thrust belt, western US Cordillera, Geology, 17, 59-62, 1989.
    • Miller, E. L. and Gans, P. B.: Geologic map of the Cove Quadrangle, Nevada, Field Studies Map 22, Nevada Bureau of Mines and Geology, Reno, Nevada, 1999.
    • Miller, E. L., Gans, P. B., and Garing, J.: The Snake Range decollement: an exhumed mid-Tertiary ductile-brittle transition, Tectonics, 2-3, 239-263, 1983.
    • Miller, E. L., Dumitru, T. A., Brown, R. W., and Gans, P. B.: Rapid Miocene slip on the Snake Range-Deep Creek Range fault system, east-central Nevada, Geol. Soc. Am. Bull., 111, 886-905, 1999.
    • Misch, P. H.: Regional structural reconnaissance in centralnortheast Nevada and some adjacent areas: Observations and interpretations, International Association of Petroleum Geologists 11th Annual Field Conference Guidebook, International Association of Petroleum Geologists, 17-42, 1960.
    • Misch, P. and Hazzard, J. C.: Stratigraphy and metamorphism of Late Precambrian rocks in central northeastern Nevada and adjacent Utah, Am. Assoc. Petr. Geol. B., 46, 289-343, 1962.
    • Parrish, R. R., Carr, S. D., and Parkinson, D. L.: Eocene extensional tectonics and geochronology of the southern Omineca Belt, British Columbia and Washington, Tectonics, 7, 181-212, 1988.
    • Paterson, M. S.: The thermodynamics of water in quartz, Phys. Chem. Miner., 13, 245-255, 1986.
    • Paterson, M. S. and Luan, F. C.: Quartzite rheology under geological conditions, Geological Society London Special Publications, 54, 299-307, 1990.
    • Platt, J. P. and Behr, W. M.: Deep structure of lithospheric fault zones, Geophys. Res. Lett., 38, L24308, doi:10.1029/2011GL049719, 2011a.
    • Platt, J. P. and Behr, W. M.: Grainsize evolution in ductile shear zones: Implications for strain localization and the strength of the lithosphere, J. Struct. Geol., 33, 537-550, doi:10.1016/j.jsg.2011.01.018, 2011b.
    • Platt, J. P., Behr, W. M., and Cooper, F. J.: Metamorphic Core Complexes: Windows into the Mechanics and Rheology of the Crust, J. Geol. Soc., TC1055, doi:10.1144/jgs2014-036, 2015.
    • Post, A. and Tullis, J.: The rate of water penetration in experimentally deformed quartzite: implications for hydrolytic weakening, Tectonophysics, 295, 117-137, 1998.
    • Post, A. D., Tullis, J., and Yund, R. A.: Effects of chemical environment on dislocation creep of quartzite, J. Geophys. Res., 101, 22143-22155, 1996.
    • Rey, P. F., Teyssier, C., Kruckenberg, S. C., and Whitney, D. L.: Viscous collision in channel explains double domes in metamorphic core complexes, Geology, 39, 387-390, 2011.
    • Rybacki, E., Gottschalk, M., Wirth, R., and Dresen, G.: Influence of water fugacity and activation volume on the flow properties of fine-grained anorthite aggregates, J. Geophys. Res.-Sol. Ea., 111, B03203, doi:10.1029/2005JB003663, 2006.
    • Schleicher, A. M., van der Pluijm, B. A., and Warr, L. N.: Chloritesmectite clay minerals and fault behavior: New evidence from the San Andreas Fault Observatory at Depth (SAFOD) core, Lithosphere, 4, 209-220, 2012.
    • Scott, R. J. and Lister, G. S.: Detachment faults: Evidence for a low-angle origin, Geology, 20, 833-836, 1992.
    • Selverstone, J., Axen, G. J., and Luther, A. L.: Fault localization controlled by fluid infiltration into mylonites: formation and strength of low-angle normal faults in the midcrustal brittle-plastic transition, J. Geophys. Res., 117, B06210, doi:10.1029/2012JB009171, 2012.
    • Sibson, R. H.: Continental fault structure and the shallow earthquake source, J. Geol. Soc., 140, 741-768, 1983.
    • Singleton, J. S. and Mosher, S.: Mylonitization in the lower plate of the Buckskin-Rawhide detachment fault, west-central Arizona: Implications for the geometric evolution of metamorphic core complexes, J. Struct. Geol., 39, 180-198, doi:10.1016/j.jsg.2012.02.013, 2012.
    • Spencer, J. E. and Reynolds, S. J.: Tectonics of Mid-Tertiary extension along a transect through west central Arizona, Tectonics, 10, 1204-1221, 1991.
    • Stipp, M. and Tullis, J.: The recrystallized grain size piezometer for quartz, Geophys. Res. Lett., 30, 3-1-3-5, doi:10.1029/2003GL018444, 2003.
    • Stipp, M., Stünitz, H., Heilbronner, R., and Schmid, S. M.: Dynamic recrystallization of quartz: correlation between natural and experimental conditions, Geological Society of London Special Publication, 200, 171-190, 2002.
    • Sullivan, W. A. and Snoke, A. W.: Comparative anatomy of corecomplex development in the northeastern Great Basin, USA, Rocky Mountain Geology, 42, 1-29, 2007.
    • Wang, C.-Y., Okaya, D. A., Ruppert, C., Davis, G. A., Guo, T.-S., Zhong, Z., and Wenk, H. R.: Seismic reflectivity of the Whipple Mountain shear zone in Southern California, J. Geophys. Res., 94, 2989-3005, 1989.
    • Wernicke, B.: Cenozoic extensional tectonics of the US Cordillera, in: The Cordilleran Orogen: Conterminous US, edited by: Burchfiel, B. C., Lipman, P. W., and Zoback, M. L., Geological Society of America, Boulder, Colorado, 1992.
    • Wernicke, B. and Getty, S. R.: Intracrustal subduction and gravity currents in the deep crust: Sm-Nd, Ar-Ar, and thermobarometric constraints from the Skagit Gneiss Complex, Washington, Geol. Soc. Am. Bull., 109, 1149-1166, 1997.
    • Whitney, D. L., Teyssier, C., Rey, P. F., and Buck, W. R.: Continental and oceanic core complexes, Geol. Soc. Am. Bull., 125, 273-298, doi:10.1130/B30754.1, 2013.
    • Wong, M. S.: Evidence for Miocene reactivation of a late Cretaceous to early Tertiary shear zone in the Harcuvar and BuckskinRawhide metamorphic core complexes, Arizona, Denver, USA, 2013.
    • Wong, M. S. and Gans, P. B.: Geologic, structural, and thermochronologic constraints on the tectonic evolution of the Sierra Mazatán core complex, Sonora, Mexico: New insights into metamorphic core complex formation, Tectonics, 27, TC4013, doi:10.1029/2007TC002173, 2008.
    • Wright, J., Anderson, J., and Davis, G.: Timing of plutonism, mylonitization, and decompression in a metamorphic core complex, Geological Society of America Abstracts with Programs, 18, 201 pp., 1986.
    • Wust, S. L.: Regional correlation of extension directions in Cordilleran metamorphic core complexes, Geology, 14, 828- 830, 1986.
  • No related research data.
  • No similar publications.

Share - Bookmark

Funded by projects

Cite this article