- Open Access
Heterogeneous material distribution, an important reason for generation of strain-localized mylonite and frictional slip zones in the Hidaka metamorphic belt, Hokkaido, Japan
Earth, Planets and Space volume 56, pages1225–1232(2004)
Lithological heterogeneity of low P/T metamorphic rocks in southern area of Hidaka metamorphic belt (HMB) was formed through historical development of HMB while these rocks had been laid in ductile lower crust. Many strain-localized mylonite zones (<100 m in thickness) are preferentially developed within S-type tonalite and pelitic gneiss, which are characterized by a large modal amount of phyllosilicates (biotite+muscovite+chlorite) and quartz, compared to other lithofacies in HMB. Mylonitic foliations are more conspicuous with close to the center of the shear zone associated with increase in amounts of phyllosilicate minerals, indicating fluidenhanced weakening mechanisms were operated in plastic shear zones. Pseudotachylyte veins are observed exclusively in these mylonite zones, which were generated during exhumation stage of HMB. We conclude the seismic slip zones in southern HMB had been initiated in the ductile lower crust by concentration of localized plastic shear zones within the phyllosilicate- and quartz-rich lithofacies, which were heterogeneously formed by old metamorphic and magmatic events. Then these zones were further weakened by fluid-enhanced plastic deformation, and finally seismic slips occurred at the bottom of seismogenic upper crust, during exhumation of HMB.
Bos, B. and C. J. Spires, Experimental investigation into the microstructural and mechanical evolution of phyllosilicate-bearing fault rock under conditions favoring pressure solution, Jour. Struct. Geol., 23(8), 1187–1202, 2001.
Bos, B. and C. J. Spires, Frictional viscous flow of phyllosilicate bearing fault rock; Microphysical model and implications for strength profile, Jour. Geophys. Res., 107, 10.1029/2001 JB000301, 2002.
Fitz Gerald, J. D. and H. Stünitz, Deformation of granotoids at low metamorphic grade I: Reactions and grain size reduction, Tectonophysics, 221, 269–297, 1993.
Hippertt, J. F., Breakdown of feldspar, volume gain and lateral mass transfer during mylonitization of granotoids in a low metamorphic grade shear zone, Jour. Struct. Geol., 20, 175–193, 1998.
Komatsu, M., T. Toyoshima, Y. Osanai, and M. Arai, Prograde and anatectic reactions in the deep arc crust exposed in the Hidaka metamorphic belt, Hokkaido, Japan, Lithos, 33, 31–49, 1994.
Logan, J. M. and K. A. Rauenzahn, Frictional dependence of gouge mixtures of quartz and montmorillonite on velocity, composition and fabric, Tectonophysics, 144, 87–108, 1987.
Lonka, H., K. Schulmann, and Z. Venera, Ductile deformation of tonalite in the Suomusjarvi shear zone, southwestern Finland, Jour. Struct. Geol., 20, 783–798, 1998.
Masuda, T. and A. Fujimura, Microstructural development of fine-grained quartz aggregates by syntectonic recrystallization, Tectonophysics, 72, 105–128, 1981.
Obara, T., Structural analysis and petrological study of the Hidaka metamorphic belt in the Horoman-gawa River area, Unpublished master thesis of Niigata University, 1997 (in Japanese with English abstract).
Osanai, Y., M. Komatsu, and M. Owada, Metamorphism and granite genesis in the Hidaka metamorphic Belt, Hokkaido Japan, Jour. Metamorphic Geol., 9, 111–124, 1991
Osanai, Y., M. Owada, and T. Kawasaki, Tertiary deep crustal ultrametamorphism in the Hidaka metamorphic belt, northern Japan, Jour. Metamorphic. Geol., 10, 401–414, 1992.
Osanai, Y., M. Owada, T. Shimura, T. Kawasaki, and B. J. Hensen, Crustal anatexis and related acidic magma genesis in the Hidaka metamorphic belt, Hokkaido, northern Japan, Mem. Geol. Soc. Japan, 47, 29–42, 1997 (in Japanese with English abstract).
Owada, M., Y. Osanai, and H. Kagami, Rb-Sr isochron ages for hornblende tonalite from the southeastern part of the Hidaka metamorphic belt, Hokkaido, Japan: Implication for timing of peak metamorphism, Mem. Geol. Soc. Japan, 47, 21–27, 1997 (in Japanese with English abstract).
Passchier, C. W. and R. A. J. Trouw, Microtectonics, Springer-Berlag, Berlin/Heidelberg, 289 p., 1996.
Shimada, K., H. Tanaka, T. Toyoshima, T. Obara, and T. Niizato, Occurrence of mylonite zones and pseudotachylyte veins around the base of the upper crust: an example from the southern Hidaka Metamorphic Belt, Samani area, Hokkaido, Japan, Earth Planets Space, 56, this issue, 1219–1225, 2004.
Shimura, T., M. Komatsu, S. Tsutai, M. Owada, and Y. Takahashi, Thermal and chemical interaction between granitic magmas and wall rocks in the Hidaka metamorphic belt, northern Japan, Mem. Geol. Soc. Japan, 47, 1–12, 1997 (in Japanese with English abstract).
Sholtz, C. H., The brittle-plastic transition and the depth of seismogenic faulting, Geol. Runds., 77, 319–328, 1988.
Stünitz, H. and J. D. Fitz Gerald, Deformation of granotoids at low metamorphic grade II: Granular flow in albite-rich mylonites, Tectonophysics, 221, 299–324, 1993.
Toyoshima, T., Pseudotachylyte from the main zone of the Hidaka metamorphic belt, Hokkaido, northern Japan, Jour. Metamor. Geol., 8, 507–523, 1990.
Toyoshima, T., Tectonic evolution of the Hidaka metamorphic belt and its implication in late Cretaceous—middle Tertiary tectonics of Hokkaido, Japan, Jour. Fac. Sci., Niigata Univ., Ser. E, 8, 1–107, 1991.
Toyoshima, T., M. Komatsu, and T. Shimura, Tectonic evolution of lower crustal rocks in an exposed magmatic arc section in the Hidaka metamorphic belt, Hokkaido, northern Japan, The Island Arc, 3, 182–198, 1994.
Toyoshima, T., T. Obara, T. Niizato, H. Tanaka, K. Shimada, M. Komatsu, and Y. Wada, Pseudotachylytes and related fault rocks from the Hidaka metamorphic belt, Hokkaido, northern Japan, Earth Planets Space, 56, this issue, xxx–xxx, 2004.
About this article
Cite this article
Tanaka, H., Shimada, K., Toyoshima, T. et al. Heterogeneous material distribution, an important reason for generation of strain-localized mylonite and frictional slip zones in the Hidaka metamorphic belt, Hokkaido, Japan. Earth Planet Sp 56, 1225–1232 (2004). https://doi.org/10.1186/BF03353344
- Hidaka metaorphic belt
- rupture generation mechanism