scholarly journals Simple Topographic Parameter Reveals the Along-Trench Distribution of Frictional Properties on a Shallow Plate Boundary Fault

2021 ◽  
Author(s):  
Hiroaki Koge ◽  
Juichiro Ashi ◽  
Jin-Oh Park ◽  
Ayumu Miyakawa ◽  
Suguru Yabe
Keyword(s):  
Spatial Distribution ◽  
Friction Coefficient ◽  
Subduction Zones ◽  
Slope Angle ◽  
Plate Boundary ◽  
Boundary Fault ◽  
Frictional Properties ◽  
Topographic Parameter ◽  
Dip Angle ◽  
Taper Model

Abstract The critical taper model of a sedimentary wedge best describes the first-order mechanics of a subduction zone wedge. The tapered wedge geometry, which is conventionally defined by two parameters, the slope angle and the basal dip angle, is responsible for the strength of a megathrust. By applying this theoretical model to subduction zones, fault frictional properties and earthquake occurrences can be compared among subduction zones, and within a single subduction zone, the spatial distribution or temporal change of fault strength can be investigated. The slope angle can be accurately estimated from bathymetry data, but the basal dip angle must be inferred from the subsurface structure, and it requires highly accurate depth-converted seismic reflection profiles. Thus, application of the critical taper model is often limited by a lack of a sufficient number of highly accurate profiles, and the spatial distribution of frictional coefficients must be inferred from relatively few data, generally less than a dozen points. To improve this situation, we revisited the theoretical formula of the critical taper model. We found that the effect of the décollement dip angle β on the critical taper model of a sedimentary wedge is negligible when the pore fluid pressure ratio is high or internal friction is small, conditions which are met in many subduction zones. Therefore, this finding allows frictional variation to be approximated by using only the slope angle variation obtained from the bathymetry. We applied this approximation to the Japan Trench as an example of this approximation, and were able to estimate the friction coefficient distribution on the shallow plate boundary fault from 71 data points. We found that the area where the friction coefficient was smaller than the mean corresponded to the segment where a large coseismic shallow rupture occurred during the 2011 Tohoku-oki earthquake (Mw 9.0). This result shows that by approximating tapered wedge geometry using a simple topographic parameter that can be obtained from existing global bathymetry, we can quickly estimate the distribution of frictional properties on a plate boundary fault along a trench and related seismic activity.

scholarly journals The spatial-temporal total friction coefficient of the fault viewed from the seismo-electromagnetic theory

2019 ◽  
Author(s):  
Patricio Venegas-Aravena ◽  
Enrique G. Cordaro ◽  
David Laroze
Keyword(s):  
Spatial Distribution ◽  
Friction Coefficient ◽  
Stress Drop ◽  
Electromagnetic Theory ◽  
Frictional Properties ◽  
Stress Changes ◽  
Plastic Rock ◽  
Dip Angle ◽  
Lithospheric Stress

Abstract. Recently, it has been shown theoretically how the lithospheric stress changes could be linked with magnetic anomalies, frequencies, spatial distribution and the magnetic-moment magnitude relation using the electrification of microfractures in the semi brittle-plastic rock regimen [Venegas-Aravena et al. Nat. Hazards Earth Syst. Sci. 19, 1639–1651 (2019)]. However, this Seismo-electromagnetic Theory still has not shown any relation, approach or changes in the fault's properties in order to be linked with the beginning of seismic rupture process itself. In this work we show the first and simple theoretical approach to one of the key parameters for seismic ruptures as is the friction coefficient and the stress drop. We use sigmoidal stress changes in the non-elastic regimen within lithosphere described before to figure out the temporal changes in frictional properties of faults. We also use a long term friction coefficient approximation that can depend on the fault dip angle, four parameters that weight the first and second stress derivative, the spatial distribution of the non-constant stress changes and the stress drop. It is found that the friction coefficient is not constant in time and evolve previous and after the earthquake occurs regardless of the (non-zero) weight used. When we use a dip angle close to 30 degrees and the contribution of the second derivative is more significant than the first derivative, the friction coefficient increase previous the earthquake. Then, the earthquake occurs and the friction drop. Finally, the friction coefficient increases and decreases after the earthquake. When there is no contribution of stress changes in the semi brittle-plastic regimen, no changes are expected in the friction coefficient.

scholarly journals The spatial–temporal total friction coefficient of the fault viewed from the perspective of seismo-electromagnetic theory

2020 ◽  
Vol 20 (5) ◽  
pp. 1485-1496
Author(s):  
Patricio Venegas-Aravena ◽  
Enrique G. Cordaro ◽  
David Laroze
Keyword(s):  
Spatial Distribution ◽  
Friction Coefficient ◽  
Stress Drop ◽  
Electromagnetic Theory ◽  
Earthquake Occurrence ◽  
Sigmoidal Functions ◽  
Stress Changes ◽  
Plastic Rock ◽  
Dip Angle ◽  
Lithospheric Stress

Abstract. Recently, it has been shown theoretically how the lithospheric stress changes could be linked with magnetic anomalies, frequencies, spatial distribution and the magnetic-moment magnitude relation using the electrification of microfractures in the semibrittle–plastic rock regime (Venegas-Aravena et al., 2019). However, this seismo-electromagnetic theory has not been connected with the fault's properties in order to be linked with the onset of the seismic rupture process itself. In this work we provide a simple theoretical approach to two of the key parameters for seismic ruptures which are the friction coefficient and the stress drop. We use sigmoidal functions to model the stress changes in the nonelastic regime within the lithosphere. We determine the temporal changes in frictional properties of faults. We also use a long-term friction coefficient approximation that depends on the fault dip angle and four additional parameters that weigh the first and second stress derivative, the spatial distribution of the nonconstant stress changes, and the stress drop. We found that the friction coefficient is not constant in time and evolves prior to and after the earthquake occurrence regardless of the (nonzero) weight used. When we use a dip angle close to 30∘ and the contribution of the second derivative is more significant than that of the first derivative, the friction coefficient increases prior to the earthquake. During the earthquake event the friction drops. Finally, the friction coefficient increases and decreases again after the earthquake occurrence. It is important to mention that, when there is no contribution of stress changes in the semibrittle–plastic regime, no changes are expected in the friction coefficient.

scholarly journals The fluid budget of a continental plate boundary fault: Quantification from the Alpine Fault, New Zealand

2016 ◽  
Vol 445 ◽  
pp. 125-135 ◽  
Author(s):  
Catriona D. Menzies ◽  
Damon A.H. Teagle ◽  
Samuel Niedermann ◽  
Simon C. Cox ◽  
Dave Craw ◽  
...  
Keyword(s):  
New Zealand ◽  
Plate Boundary ◽  
Boundary Fault ◽  
Continental Plate ◽  
Alpine Fault

scholarly journals Structure and lithology of the Japan Trench subduction plate boundary fault

Tectonics ◽  
2015 ◽  
Vol 34 (1) ◽  
pp. 53-69 ◽  
Author(s):  
James D. Kirkpatrick ◽  
Christie D. Rowe ◽  
Kohtaro Ujiie ◽  
J. Casey Moore ◽  
Christine Regalla ◽  
...  
Keyword(s):  
Plate Boundary ◽  
Japan Trench ◽  
Boundary Fault

scholarly journals Alteration and dehydration of subducting oceanic crust within subduction zones: implications for décollement step-down and plate-boundary seismogenesis

2017 ◽  
Vol 69 (1) ◽  
Author(s):  
Jun Kameda ◽  
Sayako Inoue ◽  
Wataru Tanikawa ◽  
Asuka Yamaguchi ◽  
Yohei Hamada ◽  
...  
Keyword(s):  
Oceanic Crust ◽  
Subduction Zones ◽  
Plate Boundary ◽  
Step Down

Coseismic slip propagation on the Tohoku plate boundary fault facilitated by slip-dependent weakening during slow fault slip

2017 ◽  
Vol 44 (17) ◽  
pp. 8749-8756 ◽  
Author(s):  
Yoshihiro Ito ◽  
Matt J. Ikari ◽  
Kohtaro Ujiie ◽  
Achim Kopf
Keyword(s):  
Plate Boundary ◽  
Fault Slip ◽  
Coseismic Slip ◽  
Boundary Fault

Icequake streaks linked to potential mega-scale glacial lineations beneath an Antarctic ice stream

Geology ◽  
2019 ◽  
Vol 48 (2) ◽  
pp. 99-102
Author(s):  
C. Grace Barcheck ◽  
Susan Y. Schwartz ◽  
Slawek Tulaczyk
Keyword(s):  
Mechanical Properties ◽  
Spatial Distribution ◽  
High Porosity ◽  
Back Projection ◽  
West Antarctica ◽  
S Wave ◽  
Frictional Properties ◽  
Ice Stream ◽  
Bed Materials ◽  
Bed Material

Abstract Icequakes radiating from an ice-stream base provide insights into otherwise difficult to observe sub-kilometer-scale basal heterogeneity. We detect basal icequakes beneath an ∼3-km-wide seismic sensor network installed on the Whillans Ice Plain (WIP) in West Antarctica, and we use S-wave back-projection to detect and locate thousands of basal icequakes occurring over 14 and 21 days in January 2014 and 2015, respectively. We find flow-parallel streaks of basal icequakes beneath the WIP, which we conjecture are related to the presence of mega-scale glacial lineations (MSGLs) indicated by ice-penetrating radar, with at least one streak originating in a local trough adjacent to a MSGL. Patterned basal seismicity can be caused by systematic spatial variation in basal pore pressure, bed-material frictional properties, or both. We interpret these flow-parallel icequake streaks as being due to frictionally heterogeneous bed materials in the presence of a streamlined ice-stream bed: bedform ridges correspond to aseismic, high-porosity deforming till, and some troughs to ephemeral exposures of deeper, seismogenic material such as lodged till or older sediments or rocks. Our results are consistent with MSGL formation by either erosion in troughs to expose deeper seismogenic material, or deposition of aseismic high-porosity till in bedform highs. Our results also suggest that evolving subglacial geomorphology can impact basal traction by reorganizing the spatial distribution of basal materials with varying mechanical properties.

scholarly journals Frictional Properties and Seismogenic Potential of Caprock Shales

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6275
Author(s):  
Bahman Bohloli ◽  
Magnus Soldal ◽  
Halvard Smith ◽  
Elin Skurtveit ◽  
Jung Chan Choi ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
North Sea ◽  
Co2 Storage ◽  
Test Procedure ◽  
Shear Velocity ◽  
Frictional Properties ◽  
The North ◽  
Slip Event ◽  
The North Sea ◽  
Direct Shear Apparatus

Fractures and faults are critical elements affecting the geomechanical integrity of CO2 storage sites. In particular, the slip of fractures and faults may affect reservoir integrity and increase potential for breach, may be monitored via the resulting seismicity. This paper presents an experimental study on shale samples from Draupne and Rurikfjellet formations from the North Sea and Svalbard, Norway, using a laboratory test procedure simulating the slip of fractures and faults under realistic stress conditions for North Sea CO2 storage sites. The motivation of the study is to investigate whether the slip along the fractures within these shales may cause detectable seismic events, based on a slip stability criterion. Using a direct shear apparatus, frictional properties of the fractures were measured during shearing, as a function of the shear velocity and applied stress normal to the fracture. We calculated the friction coefficient of the fractures during the different stages of the shear tests and analysed its dependency on shear velocity. Information on velocity-dependent friction coefficient and its evolution with increasing slip were then used to assess whether slip was stable (velocity-strengthening) or unstable (velocity-weakening). Results showed that friction coefficient for both Draupne and Rurikfjellet shales increased when the shear velocity was increased from 10 to 50 µm/s, indicating a velocity-strengthening behaviour. Such a behaviour implies that slip on fractures and faults within these formations may be less prone to producing detectable seismicity during a slip event. These results will have implications for the type of techniques to be used for monitoring reservoir and caprock integrity, for instance, for CO2 storage sites.

scholarly journals Anisotropy of Graphene Nanoflake Diamond Interface Frictional Properties

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1425 ◽  
Author(s):  
Ji Zhang ◽  
Ehsan Osloub ◽  
Fatima Siddiqui ◽  
Weixiang Zhang ◽  
Tarek Ragab ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Friction Force ◽  
Md Simulations ◽  
Equilibrium Distance ◽  
Sliding Angle ◽  
Stick Slip ◽  
Single Crystalline ◽  
Frictional Properties ◽  
Diamond Substrate ◽  
Graphene Nanoflake

Using molecular dynamics (MD) simulations, the frictional properties of the interface between graphene nanoflake and single crystalline diamond substrate have been investigated. The equilibrium distance between the graphene nanoflake and the diamond substrate has been evaluated at different temperatures. This study considered the effects of temperature and relative sliding angle between graphene and diamond. The equilibrium distance between graphene and the diamond substrate was between 3.34 Å at 0 K and 3.42 Å at 600 K, and it was close to the interlayer distance of graphite which was 3.35 Å. The friction force between graphene nanoflakes and the diamond substrate exhibited periodic stick-slip motion which is similar to the friction force within a graphene–Au interface. The friction coefficient of the graphene–single crystalline diamond interface was between 0.0042 and 0.0244, depending on the sliding direction and the temperature. Generally, the friction coefficient was lowest when a graphene flake was sliding along its armchair direction and the highest when it was sliding along its zigzag direction. The friction coefficient increased by up to 20% when the temperature rose from 300 K to 600 K, hence a contribution from temperature cannot be neglected. The findings in this study validate the super-lubricity between graphene and diamond and will shed light on understanding the mechanical behavior of graphene nanodevices when using single crystalline diamond as the substrate.

Sign in / Sign up

Export Citation Format

Share Document