Article
Geosciences, Multidisciplinary
Chenglong Li, Tao Li, James Hollingsworth, Yingfeng Zhang, Li Qian, Xinjian Shan
Summary: The 2021 M-w 7.4 Maduo earthquake in the eastern Tibetan Plateau had a surface deformation zone characterized by multiple distinct surface rupture segments and segments with no surface ruptures. By analyzing satellite images, surface displacement and shear-strain fields were derived, revealing a rupture strain threshold ranging from 0.8% to 1.8%. This threshold, which decreases with the fault's structural maturity, is generally consistent with laboratory measurements of intact rocks and higher than the commonly-assumed strain threshold for inelastic deformation (0.5%).
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Lu Yao, Shengli Ma, Giulio Di Toro
Summary: This paper presents experimental evidence of thermal pressurization (TP) weakening of seismic faults and suggests that TP processes could be significantly promoted by wear-induced sealing during earthquakes, even for relatively permeable faults.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Geological
Jingqi Huang, Xiaohui Chen, Xu Zhao, Mi Zhao
Summary: This study aims to investigate the nonlinear response of tunnels under coseismic displacement induced by strike-slip fault. The numerical results show that the tunnel might suffer tensile damages under coseismic displacement, and the damage degree is influenced by the angle of the tunnel axis, epicentral distance, and earthquake magnitude.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2022)
Article
Mechanics
Thomasina V. V. Ball, Neil J. J. Balmforth
Summary: This paper investigates the dynamics of peeling of a viscous fluid spreading underneath a deformable surface skin or crust. The rate of advance is controlled by the peeling dynamics at the fluid front rather than bulk self-similar flow. The study focuses on a skin that deforms either viscously or plastically, where the thin plate of material is governed by the Herschel-Bulkley constitutive law. The research examines how such a skin controls viscous flow underneath, considering constant flux and different types of spreading currents.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Environmental Sciences
Jiuyuan Yang, Caijun Xu, Yangmao Wen
Summary: On January 23 and March 25, 2022, two right-lateral strike-slip earthquakes with magnitudes larger than 5.5 occurred near Hala Lake in northeastern Tibet. These two events are the largest since the 1927 Hala Lake earthquake. The lack of surface rupture makes it difficult to determine the seismogenic faults and coseismic rupture behaviors of the two events. However, studying these events can provide valuable insights into the seismic hazard of the region.
Article
Geosciences, Multidisciplinary
Priyom Roy, Tapas R. Martha, K. Vinod Kumar, Prakash Chauhan
Summary: On June 21, 2022, a magnitude 6.0 earthquake struck eastern Afghanistan, causing severe damage in the Khost and Paktika provinces. With the epicenter located southwest of Khost city, the earthquake resulted in over 1000 deaths and several thousand injuries. Deformation modelling and source characterization using satellite data provide valuable information for seismic hazard management.
Article
Geochemistry & Geophysics
Nannan Guo, Yanqiang Wu, Qingyun Zhang
Summary: Through investigating the M-S 6.9 Menyuan earthquake, physical models were constructed using InSAR and GNSS data to study the coseismic and pre-seismic deformation associated with the event. The results indicate that the earthquake mainly exhibited left-lateral strike-slip deformation in a 30 x 25 km region, with a maximum fault slip of 3.81 m.
PURE AND APPLIED GEOPHYSICS
(2022)
Article
Engineering, Aerospace
Qingyun Zhang, Yanqiang Wu, Nannan Guo, Changyun Chen
Summary: The Qinghai Maduo Ms7.4 earthquake is the only earthquake with a magnitude of > 7 that has occurred within the Bayan Har Block in the past 70 years. Using InSAR technology and field investigations, researchers obtained the fault slip distributions and found that the earthquake was predominantly left-lateral strike-slip with a seismic moment of similar to Mw7.5. Furthermore, the Maduo earthquake occurred in East Kunlun, characterized by the largest maximum shear strain rate.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Wei Feng, Zechao Bai, Jinwei Ren, Shuaitang Huang, Lin Zhu
Summary: A M-S 6.6 earthquake occurred in Jinghe County, Bortala Mongol Autonomous Prefecture of Xinjiang Uygur Autonomous Region on August 9, 2017. The seismic analysis revealed typical characteristics of thrust faulting, with main slip concentrated at a depth of 10-20 km. Aftershocks and maximum deformation area were both located on the west side of the mainshock, confirming a unilateral rupture feature.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geochemistry & Geophysics
Kefeng He, Caijun Xu, Yangmao Wen
Summary: This study investigates the coseismic and post-seismic deformations of the 2019 Ridgecrest earthquake sequence using space geodetic data. The results show a pronounced shallow slip deficit during the earthquake, with most of the post-seismic slip occurring at depths of 3-8 km. Viscosity modeling suggests a lower bound of approximately 8.0 x 10(17) Pa s for the upper mantle viscosity, and reveals lateral heterogeneous relaxation processes in the northeast and southwest ECSZ.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Mechanics
Mohit P. Dalwadi, Radu Cimpeanu, Hilary Ockendon, John Ockendon, Tom Mullin
Summary: Experiments have shown that a horizontal cylinder placed on a vertically moving belt coated with viscous fluid can levitate at a fixed height and rotate around its own axis at a specific belt velocity. By developing a model and utilizing a combination of asymptotic analysis and direct numerical simulation, researchers have successfully established a relationship between the belt speed and cylinder rotation rate, which has been validated against experimental results.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Geosciences, Multidisciplinary
Chunwei Sun, Sixiang Ling, Siyuan Zhao, Hong Wen, Sen Wang
Summary: This study investigates the seismic characteristics and fault distribution of the Xingwen and Changning earthquakes using surface deformation measurements and aftershock sequences. The findings suggest that water injection may have contributed to the occurrence of the earthquakes.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Multidisciplinary Sciences
Erin McEwan, Timothy Stahl, Andrew Howell, Rob Langridge, Matthew Wilson
Summary: Surface-rupturing earthquakes can cause sudden changes in rivers by displacing faults. Although there have been several documented cases of fault rupture-induced river avulsions (FIRAs), the factors influencing these phenomena have not been thoroughly studied. In this study, a case study from the 2016 Kaikoura earthquake in New Zealand was used to model the coseismic avulsion of a major braided river that experienced a -7m vertical and -4m horizontal offset. The results show that a simple two-dimensional hydrodynamic model can accurately reproduce the avulsion characteristics. This research highlights the importance of considering fault deformation in flood hazard models to properly assess the extent and severity of inundation following large earthquakes.
Article
Mechanics
A. J. Hutchinson, R. J. Gusinow, M. Grae Worster
Summary: We study a viscous gravity current confined to the space between two parallel plates. The flow is divided into an inner region in contact with both plates and an outer annular region along the lower plate. A theoretical model based on a dimensionless parameter is proposed to describe the flow dynamics. Experimental results match the major aspects of the model, but other physics are clearly involved, indicating that a single non-dimensional parameter is not sufficient to fully capture the flow behavior.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Geochemistry & Geophysics
G. Romagnoli, F. Pavano, G. Tortorici, S. Catalano
Summary: During the Mw 4.9 earthquake of December 26, 2018, an 8 km long arc-shaped coseismic fracture belt formed along the southeastern flank of Etna Volcano in Sicily, Italy. The seismic event triggered a series of structural deformations with different characteristics and movement directions along the northern and southern segments of the fracture belt. The study suggests that the 2018 seismic event was a result of the interaction between regional tectonics and volcanic processes, as shown by large scale geodetic data.
Article
Materials Science, Ceramics
Linfeng Ding, Karan Doss, Yongjian Yang, Kuo-Hao Lee, Michal Bockowski, Sylvie Demouchy, Manuel Thieme, Benedikt Ziebarth, Qingwei Wang, Morten M. Smedskjaer, John C. Mauro
Summary: The study investigates the effect of pressure history on the relaxation behavior of borosilicate glasses, finding that high-pressure treatment affects the glass relaxation properties. Additionally, a new relaxation model is proposed and verified for volume recovery data under different compression methods, showing the pressure and temperature dependence of volume relaxation.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Geosciences, Multidisciplinary
Jiten Pattnaik, Sylvie Demouchy, Sujoy Ghosh
Summary: This study reports the first hydrogen concentrations in mantle minerals from the Eastern Dharwar craton in India, with olivine, pyroxenes, and garnet showing different levels of water content. The variable hydrogen concentrations in garnet may be influenced by nano-scale inclusions. The reconstructed hydrogen bulk concentrations in Dharwar peridotites are lower than those estimated for the lithospheric mantle, suggesting a possible relationship to proto-kimberlite melts with low water activity.
PRECAMBRIAN RESEARCH
(2021)
Article
Multidisciplinary Sciences
Vahid Samae, Patrick Cordier, Sylvie Demouchy, Caroline Bollinger, Julien Gasc, Sanae Koizumi, Alexandre Mussi, Dominique Schryvers, Hosni Idrissi
Summary: The mechanical properties of olivine-rich rocks are crucial for understanding the mechanical coupling between Earth's lithosphere and asthenosphere. Additional deformation mechanisms are required in olivine due to the lack of slip systems, with current lack of consensus on the mechanisms of grain-boundary sliding in olivine. This proposed mechanism of grain-boundary mobility triggering plastic processes in olivine-rich rocks could be significant in high-stress deep Earth conditions.
Article
Geochemistry & Geophysics
Sylvie Demouchy, Olivier Alard
Summary: Our study investigates the coupling of various elements in olivines from different geological settings, revealing the diverse behavior of hydrogen and other trace elements. The concentrations of hydrogen, minor, trace, and ultra-trace elements in olivines are influenced by the petrological origins, with hydrogen showing peculiar characteristics. The presence of hydrogen is inversely correlated with certain impurities, indicating competitive behavior for vacancies, but also shows positive correlation with Ti, suggesting complex mechanisms at play in olivine.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2021)
Article
Multidisciplinary Sciences
Cristiano Collettini, Telemaco Tesei, Fabio Trippetta, Marco M. Scuderi, Eliza Richardson, Chris Marone, Giacomo Pozzi, Cecilia Viti
Summary: Experimental studies on rock deformation have shown that solid samples with well-developed foliation exhibit lower friction compared to powdered equivalents, with sliding along phyllosilicate-rich foliation surfaces being the primary reason for reduced friction. Additionally, micro-and nano-structural analyses reveal that high friction in powdered rocks is due to fracturing, grain rotation, translation, and associated dilation, highlighting the importance of foliation in influencing the frictional properties of faults.
JOVE-JOURNAL OF VISUALIZED EXPERIMENTS
(2021)
Article
Geochemistry & Geophysics
G. Volpe, G. Pozzi, E. Carminati, M. R. Barchi, M. M. Scuderi, E. Tinti, L. Aldega, C. Marone, C. Collettini
Summary: Crustal seismicity usually occurs within the seismogenic layer, which is typically below 10 km depth, and its lower boundary is influenced by the properties of the sedimentary cover and rock. Studies in the central-northern Apennines have shown that seismic sequences primarily occur within the sedimentary cover, indicating the significant role of the basement in dictating the depth of the seismogenic zone.
EARTH AND PLANETARY SCIENCE LETTERS
(2022)
Article
Geochemistry & Geophysics
Giacomo Pozzi, Marco M. Scuderi, Elisa Tinti, Manuela Nazzari, Cristiano Collettini
Summary: Fault stability is closely related to the frictional and healing properties of fault rocks and associated fabrics. The reactivation and slip behavior of dolomite-anhydrite analog faults are controlled by fault fabrics. The study reveals that changes in normal stress can result in different fault behaviors, such as large stress drops and high slip velocities, or low stress drops and slow stick-slip events. The integration of microstructural and mechanical data suggests that frictional and chemically assisted healing processes play a relevant role in developing large instabilities in natural faults. Additionally, fault rock heterogeneity modulates the slip velocity function and the dynamics of repeating stick-slip cycles.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Materials Science, Multidisciplinary
Hosni Idrissi, Armand Beche, Nicolas Gauquelin, Ihtasham Ul-Haq, Caroline Bollinger, Sylvie Demouchy, Johan Verbeeck, Thomas Pardoen, Dominique Schryvers, Patrick Cordier
Summary: Intragranular amorphization shear lamellae are observed in deformed olivine aggregates, and their formation and propagation are associated with crystal defects and rotational nanodomains. Hence, stress-induced amorphization in olivine is a result of a direct crystal-to-amorphous transformation caused by shear instability, rather than mechanical destabilization.
Article
Geochemistry & Geophysics
Nico Bigaroni, Marco Maria Scuderi, Frederic Cappa, Yves Guglielmi, Christophe Nussbaum, Luca Aldega, Giacomo Pozzi, Cristiano Collettini
Summary: The Opalinus Clay is an important potential sealing horizon for radioactive waste repositories and carbon storage. Laboratory experiments show that relative humidity, grain size, and normal stress affect the frictional properties and stability of fault analogues. Increasing humidity decreases the friction coefficient and increases the stability parameter, while increasing normal stress leads to a transition from localized to distributed deformation.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2023)
Article
Geosciences, Multidisciplinary
G. Volpe, G. Pozzi, C. Collettini
Summary: A systematic characterization of mineralogy, fabric, and frictional properties of natural gouges was performed to distinguish between different fabric types. The Y-B-P-R fabric is typically found in frictionally strong, granular-rich faults, while the S-C-C ' fabric is observed in phyllosilicate-rich faults.
JOURNAL OF STRUCTURAL GEOLOGY
(2022)
Article
Geology
G. Volpe, G. Pozzi, M. E. Locchi, E. Tinti, M. M. Scuderi, C. Marone, C. Collettini
Summary: In this study, an interdisciplinary approach was used to examine the influence of rheological heterogeneities on earthquake activity. The research integrated geophysical, geological, and laboratory data and found that the basement rocks exhibited a heterogeneous structure with strong lenses surrounded by a weak matrix. Laboratory experiments showed that the matrix experienced aseismic creep while the lenses exhibited dynamic instabilities. The post-main shock loading rate increase promoted accelerated creep in the matrix, leading to seismic instabilities in the lenses in the form of clustered seismicity.
Article
Geochemistry & Geophysics
G. Volpe, G. Pozzi, C. Collettini, E. Spagnuolo, P. Achtziger-Zupanc, A. Zappone, L. Aldega, M. A. Meier, D. Giardini, M. Cocco
Summary: Fluid induced fault reactivation experiments were conducted at BedrettoLab to characterize frictional properties and permeability of a selected fault zone. Field investigation and X-ray powder diffraction analysis were used to characterize fault zone microstructures and fault gouge mineralogy. Frictional and permeability characterization were performed using BRAVA in the laboratory, and the experimental results were integrated with field investigations to identify the seismogenic potential and hydraulic stimulation feasibility of the selected fault.
Article
Mineralogy
Sylvie Demouchy, Manuel Thieme, Fabrice Barou, Benoit Beausir, Vincent Taupin, Patrick Cordier
Summary: In this study, the geometrically necessary dislocation density (rho(c)(alpha)) and disclination density (rho(theta)) in fine-grained polycrystalline olivine were quantified under various deformation conditions. The spatial distribution of both GND and disclination densities were obtained using ATEX software. The results showed that sub-grain boundaries were defined by areas with the highest GND densities, and most olivine sub-grain boundaries had a mixed character. Disclinations were found along grain boundaries, sub-grain boundaries, and at sub-grain boundary tips.
EUROPEAN JOURNAL OF MINERALOGY
(2023)