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Hikaru Kawamura - One of the best experts on this subject based on the ideXlab platform.
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statistical properties of the one dimensional burridge knopoff model of earthquakes obeying the rate and state dependent Friction Law
Physical Review E, 2017Co-Authors: Hikaru Kawamura, Yushi Ueda, Shingo Kakui, Shouji Morimoto, Takumi YamamotoAbstract:Statistical properties of the one-dimensional spring-block (Burridge-Knopoff) model of earthquakes obeying the rate- and state-dependent Friction Law are studied by extensive computer simulations. The quantities computed include the magnitude distribution, the rupture-length distribution, the main shock recurrence-time distribution, the seismic-time correlations before and after the main shock, the mean slip amount, and the mean stress drop at the main shock, etc. Events of the model can be classified into two distinct categories. One tends to be unilateral with its epicenter located at the rim of the rupture zone of the preceding event, while the other tends to be bilateral with enhanced "characteristic" features resembling the so-called "asperity." For both types of events, the distribution of the rupture length L_{r} exhibits an exponential behavior at larger sizes, ≈exp[-L_{r}/L_{0}] with a characteristic "seismic correlation length" L_{0}. The mean slip as well as the mean stress drop tends to be rupture-length independent for larger events. The continuum limit of the model is examined, where the model is found to exhibit pronounced characteristic features. In the continuum limit, the characteristic rupture length L_{0} is estimated to be ∼100 [km]. This means that, even in a hypothetical homogenous infinite fault, events cannot be indefinitely large in the exponential sense, the upper limit being of order ∼10^{3} kilometers. Implications to real seismicity are discussed.
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Rate- and State-Dependent Friction Law and Statistical Properties of Earthquakes
Europhysics Letters (EPL), 2007Co-Authors: Akio Ohmura, Hikaru KawamuraAbstract:In order to clarify how the statistical properties of earthquakes depend on the constitutive Law characterizing the stick-slip dynamics, we make an extensive numerical simulation of the one-dimensional spring-block model with the rate- and state-dependent Friction Law. Both the magnitude distribution and the recurrence-time distribution are studied with varying the constitutive parameters characterizing the model. While a continuous spectrum of seismic events from smaller to larger magnitudes is obtained, earthquakes described by this model turn out to possess pronounced ``characteristic'' features.
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rate and state dependent Friction Law and statistical properties of earthquakes
EPL, 2007Co-Authors: Akio Ohmura, Hikaru KawamuraAbstract:In order to clarify how the statistical properties of earthquakes depend on the constitutive Law characterizing the stick-slip dynamics, we make an extensive numerical simulation of the one-dimensional spring-block model with a rate- and state-dependent Friction Law. Both the magnitude distribution and the recurrence-time distribution are studied with varying the constitutive parameters characterizing the model. While a continuous spectrum of seismic events from smaller to larger magnitudes is obtained, earthquakes described by this model turn out to possess pronounced "characteristic" features.
Naoyuki Kato - One of the best experts on this subject based on the ideXlab platform.
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Complex Earthquake Cycle Simulations Using a Two-Degree-of-Freedom Spring-Block Model with a Rate- and State-Friction Law
Pure and Applied Geophysics, 2013Co-Authors: Naoyuki KatoAbstract:Numerical simulations of complex earthquake cycles are conducted using a two-degree-of-freedom spring-block model with a rate- and state-Friction Law, which has been supported by laboratory experiments. The model consisted of two blocks coupled to each other and connected by elastic springs to a constant-velocity, moving driver. By widely and systematically varying the model parameters, various slip patterns were obtained, including the periodic recurrence of seismic and aseismic slip events, and several types of chaotic behaviour. The transition in the slip pattern from periodic to chaotic is examined using bifurcation diagrams. The model system exhibits typical period-doubling sequences for some parameter ranges, and attains chaotic motion. Simple relationships are found in iteration maps of the recurrence intervals of simulated earthquakes, suggesting that the simulated slip behaviour is deterministic chaos. Time evolutions of the cumulative slip distance in chaotic slip patterns are well approximated by a time-predictable model. In some cases, both seismic and aseismic slip events occur at a block, and aseismic slip events complicate the earthquake recurrence patterns.
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a composite rate and state dependent Law for rock Friction
Geophysical Research Letters, 2001Co-Authors: Naoyuki Kato, Terry E TullisAbstract:Existing constitutive Laws of rock Friction cannot describe both observed strengthening in the absence of slip and Frictional behavior around steady-state sliding. Combining existing rate- and state-dependent Friction Laws, we propose a new Friction Law, which expresses logarithmically time-dependent healing at sliding velocities smaller than a cut-off velocity V c and approaches the so-called slip Law at velocities larger than V c. Numerical simulations show that the new Friction Law adequately explains experimental results of velocity stepping tests and slide- hold-slide tests, which have widely been used to examine velocity-, time-, and displacement-dependent property of rock Friction. Because the new Friction Law has a simple form and appears appropriate for a wide range of conditions, it is useful for application to numerical modeling of seismic cycles.
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a model for possible crustal deformation prior to a coming large interplate earthquake in the tokai district central japan
Bulletin of the Seismological Society of America, 1999Co-Authors: Naoyuki Kato, Tomowo HirasawaAbstract:We perform numerical simulations of a seismic cycle by applying a laboratory-derived Friction Law to evaluate possible crustal deformations prior to the hypothesized Tokai earthquake, which is expected to occur in the near future along the Suruga trough, central Japan. The Frictional force obeying a rate- and state-dependent Friction Law is assumed to act on the plate interface in a 2D model of the subduction zone. We test two versions of the Friction Law: the so-called slowness version and the slip version. We select model parameters on the basis of historical documents about past large earthquakes in the Tokai district and the present coupling state of the plate interface beneath the Tokai district estimated by GPS observations. Simulation results for both the slowness and the slip version are as follows: (1) The coupling region of the plate interface becomes narrower with time in the interseismic period. (2) The inland crust contracts at a nearly constant rate for most of the interseismic period. The contraction rate decreases or a change from contraction to extension takes place before the occurrence of a large interplate earthquake. (3) Significant abnormal crustal deformation precedes the earthquake, and maximum amplitudes about one day before the earthquake exceed the noise levels in the case of clear weather of borehole strainmeters installed in the Tokai district. (4) The spatiotemporal variation of aseismic sliding on the plate interface perturbs the regional stress field around the source volume of the coming earthquake, leading possibly to precursory seismic quiescence in the overriding plate and a change in focal mechanisms of small earthquakes in the subducting slab. The most significant difference in the results between the slowness version and the slip version of the Friction Law is that amplitudes of preslip and crustal deformation just before earthquakes are several times larger for the slowness version than for the slip version. Although some ambiguity remains in the present model mainly because of the incompleteness of the Friction Law and the deficiency of observational data constraining model parameters, the physical model can be improved through the comparison of predicted crustal deformation with observations. Continuous and concentrated observations of crustal deformation and seismic activity are thus important in the Tokai district to understand quantitatively the sliding process preceding a large interplate earthquake there.
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nonuniform and unsteady sliding of a plate boundary in a great earthquake cycle a numerical simulation using a laboratory derived Friction Law
Pure and Applied Geophysics, 1999Co-Authors: Naoyuki Kato, Tomowo HirasawaAbstract:—A numerical study is conducted to simulate complicated sliding behavior and earthquake activity on a subducting plate boundary. A 2-D model of a uniform elastic half-space with a semi-infinite thrust fault is set up, and the Frictional stress prescribed by a rate- and state-dependent Friction Law is assumed to act on the plate boundary fault. Spatial nonuniformity of Friction parameters representing rate-dependence of Friction and of slip-dependence of Friction are introduced in the model to obtain complicated sliding behavior in the numerical simulation. Analogs of great earthquakes that break the entire seismogenic plate boundary repeatedly occur at a constant time interval. Smaller events of seismic or aseismic sliding occur during a great earthquake cycle. Regions of rate-strengthening of Friction and of a large characteristic distance in slip-dependence of Friction behave as barriers or asperities. Rupture propagation is often arrested in such a region and a great earthquake occurs later when the region is broken. The variety of earthquake activity observed in many regions along real plate boundaries may be explained by similar nonuniformity in Friction parameters. Conversely, the Friction parameters on plate boundaries might be estimated from comparison of theoretical simulations with observations of earthquake activity. Simulation results indicate that spatiotemporal variation in stress due to aseismic sliding may play an important part in generating earthquakes.
Akio Ohmura - One of the best experts on this subject based on the ideXlab platform.
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Rate- and State-Dependent Friction Law and Statistical Properties of Earthquakes
Europhysics Letters (EPL), 2007Co-Authors: Akio Ohmura, Hikaru KawamuraAbstract:In order to clarify how the statistical properties of earthquakes depend on the constitutive Law characterizing the stick-slip dynamics, we make an extensive numerical simulation of the one-dimensional spring-block model with the rate- and state-dependent Friction Law. Both the magnitude distribution and the recurrence-time distribution are studied with varying the constitutive parameters characterizing the model. While a continuous spectrum of seismic events from smaller to larger magnitudes is obtained, earthquakes described by this model turn out to possess pronounced ``characteristic'' features.
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rate and state dependent Friction Law and statistical properties of earthquakes
EPL, 2007Co-Authors: Akio Ohmura, Hikaru KawamuraAbstract:In order to clarify how the statistical properties of earthquakes depend on the constitutive Law characterizing the stick-slip dynamics, we make an extensive numerical simulation of the one-dimensional spring-block model with a rate- and state-dependent Friction Law. Both the magnitude distribution and the recurrence-time distribution are studied with varying the constitutive parameters characterizing the model. While a continuous spectrum of seismic events from smaller to larger magnitudes is obtained, earthquakes described by this model turn out to possess pronounced "characteristic" features.
Tetsuya Kusakabe - One of the best experts on this subject based on the ideXlab platform.
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earthquake cycle simulation with a revised rate and state dependent Friction Law
Tectonophysics, 2013Co-Authors: Nobuki Kame, Satoshi Fujita, Masao Nakatani, Tetsuya KusakabeAbstract:Abstract Rate- and state-dependent Friction Law (RSF) has been recently revised by Nagata et al. (2012) ; the value of direct effect parameter has been revised to be five times greater, and a newly noticed weakening effect by shear stress has been incorporated. Using this revised RSF that seems to have eventually resolved all the known discrepancies from laboratory observations, we re-investigated the mechanics of stick-slip cycles. Using a spring-slider model, we analyzed the long-term stability and derived the critical stiffness. We then simulated stick-slip cycles with both the original and revised RSFs. Two significant differences have been recognized. 1) With the revised RSF, the state turns to decrease as early as at one-third of the recurrence interval, when the fault is still firmly locked. This contrasts to the result with the original RSF where the turning point comes much later as the slip becomes fast enough for the slip-weakening term to beat the healing term. 2) State reduction in the short-term preslip period, defined as the period since the slip velocity exceeds the load-point velocity, is three times larger for the revised RSF. The former is a direct manifestation of the stress-weakening effect, and the latter is attributed to the larger slip-weakening rate in the revised RSF. On the other hand, stress or slip velocity history did not differ very much. It is suggested that monitoring for precursory weakening of the interface, as has been successfully done by an acoustic method in the laboratory, is advantageous over the monitoring for preslip by geodetic methods, especially when we consider the revised RSF.
Julien Scheibert - One of the best experts on this subject based on the ideXlab platform.
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MEMS-based contact stress field measurements at a rough elastomeric layer: local test of Amontons’ Friction Law in static and steady sliding regimes
EDP Sciences, 2010Co-Authors: Julien Scheibert, Alexis Prevost, Joel Frelat, Eytan Katzav, Adda M Bedia, Georges DebrégeasAbstract:We present the results of recent Friction experiments in which a MEMS-based sensing device is used to measure both the normal and tangential stress fields at the base of a rough elastomer film in Frictional contact with smooth, rigid, glass indentors. We consider successively multicontacts under (i) static normal loading by a spherical indentor and (ii) Frictional steady sliding conditions against a cylindrical indentor, for an increasing normal load. In both cases, the measured fields are compared to elastic calculations assuming (i) a smooth interface and (ii) Amontons’ Friction Law. In the static case, significant deviations are observed which decrease with increasing load and which vanish when a lubricant is used. In the steady sliding case, Amontons’ Law reproduces rather satisfactorily the experiments provided that the normal/tangential coupling at the contact interface is taken into account. We discuss the origin of the difference between the Amontons fields and the measured ones, in particular the effect of the finite normal and tangential compliances of the multicontact interface
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mems based contact stress field measurements at a rough elastomeric layer local test of amontons Friction Law in static and steady sliding regimes
14th International Conference on Experimental Mechanics (ICEM14), 2010Co-Authors: Julien Scheibert, Alexis Prevost, Joel Frelat, Eytan Katzav, Adda M Bedia, Georges DebrégeasAbstract:We present the results of recent Friction experiments in which a MEMS-based sensing device is used to measure both the normal and tangential stress fields at the base of a rough elastomer film in Frictional contact with smooth, rigid, glass indentors. We con- sider successively multicontacts under (i) static normal loading by a spherical indentor and (ii) Frictional steady sliding conditions against a cylindrical indentor, for an increas- ing normal load. In both cases, the measured fields are compared to elastic calculations assuming (i) a smooth interface and (ii) Amontons' Friction Law. In the static case, signifi- cant deviations are observed which decrease with increasing load and which vanish when a lubricant is used. In the steady sliding case, Amontons' Law reproduces rather satisfacto- rily the experiments provided that the normal/tangential coupling at the contact interface is taken into account. We discuss the origin of the difference between the Amontons fields and the measured ones, in particular the effect of the finite normal and tangential compli- ances of the multicontact interface.
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mems based contact stress field measurements at a rough elastomeric layer local test of amontons Friction Law in static and steady sliding regimes
14th International Conference on Experimental Mechanics (ICEM14), 2010Co-Authors: Julien Scheibert, Alexis Prevost, Joel Frelat, Eytan Katzav, Adda M Bedia, Georges DebrégeasAbstract:We present the results of recent Friction experiments in which a MEMS-based sensing device is used to measure both the normal and tangential stress fields at the base of a rough elastomer film in Frictional contact with smooth, rigid, glass indentors. We con- sider successively multicontacts under (i) static normal loading by a spherical indentor and (ii) Frictional steady sliding conditions against a cylindrical indentor, for an increas- ing normal load. In both cases, the measured fields are compared to elastic calculations assuming (i) a smooth interface and (ii) Amontons' Friction Law. In the static case, signifi- cant deviations are observed which decrease with increasing load and which vanish when a lubricant is used. In the steady sliding case, Amontons' Law reproduces rather satisfacto- rily the experiments provided that the normal/tangential coupling at the contact interface is taken into account. We discuss the origin of the difference between the Amontons fields and the measured ones, in particular the effect of the finite normal and tangential compli- ances of the multicontact interface.
