A5050465384- earthquake and tectonic studies
- High-pressure geophysics and materials
- Geological and Geochemical Analysis
- Seismic Imaging and Inversion Techniques
- Seismology and Earthquake Studies
- Geotechnical and Geomechanical Engineering
- Rock Mechanics and Modeling
- Earthquake Detection and Analysis
- Drilling and Well Engineering
- Seismic Waves and Analysis
- Landslides and related hazards
- Hydraulic Fracturing and Reservoir Analysis
- CO2 Sequestration and Geologic Interactions
- Granular flow and fluidized beds
- Hydrocarbon exploration and reservoir analysis
- Mineral Processing and Grinding
- Tunneling and Rock Mechanics
- Geological Modeling and Analysis
- Grouting, Rheology, and Soil Mechanics
- Geological and Geophysical Studies
- Geology and Paleoclimatology Research
- Botany and Geology in Latin America and Caribbean
- Methane Hydrates and Related Phenomena
- Anomaly Detection Techniques and Applications
- Geochemistry and Geologic Mapping
Utrecht University
2016-2025
University of Southern Denmark
2019
Istituto Nazionale di Geofisica e Vulcanologia
2009-2015
Pennsylvania State University
2008-2011
Previous rotary shear experiments, performed on a halite‐muscovite fault gouge analogue system have shown that the presence of phyllosilicates, under conditions favoring operation cataclasis and pressure solution in matrix phase, can major effects frictional behavior gouges. While 100% halite muscovite samples exhibit rate‐independent frictional/brittle behavior, strength mixtures containing 10–30% is both normal stress sliding velocity‐dependent. At high velocities (>1 μ m s −1 ), such...
[1] We report on laboratory experiments designed to investigate the influence of pore pressure oscillations effective permeability fractured rock. Berea sandstone samples were in situ under triaxial stresses tens megapascals, and deionized water was forced through incipient fracture conditions steady oscillating pressure. find that short-term induce long-term transient increases samples. The magnitude enhancements scales with amplitude oscillations, changes persist well after stress...
With the advent of high-velocity shear apparatus, several experimental studies have been performed in recent years, improving our understanding evolution fault strength during seismic slip.However, these experiments were conducted under relatively low normal stress (<20 MPa) and using small cylindrical samples where a large gradient slip velocity exists across sliding surface.Given above limitations, extrapolation results to natural conditions is not trivial.Here we present from an study on...
Abstract We report ring shear experiments on simulated calcite fault gouges performed at fixed temperatures ( T ) within the range from 20°C to 600°C. The were wet, using pore fluid pressures P f of 10 ≤ 60 MPa. One series employed a constant effective normal stress 50 MPa, while in second series, was sequentially stepped 30 100 In all experiments, sliding velocity v 0.03 µm/s. results showed stable, velocity‐strengthening behavior 20°C, but weakening 100°C 550°C (for steps <3 µm/s),...
Abstract Despite the fact that phyllosilicates are ubiquitous in mature fault and shear zones, little is known about strength of phyllosilicate-bearing rocks under brittle-ductile transitional conditions where cataclasis solution-transfer processes active. In this study we explored steady-state behaviour a simulated rock, consisting muscovite halite, using brine as pore fluid. Samples were deformed rotary apparatus solution transfer to dominate deformation halite. It was found these mixtures...
Mature fault zones appear to be weaker than predicted by both theory and experiment. One explanation involves the presence of weak minerals, such as talc. However, talc is only a minor constituent most thus question arises: what proportion mineral needed satisfy models? Existing studies gouges indicate that >30% phase necessary weaken faults ‐ not supported observations. Here we demonstrate weakening can accomplished little 4 wt% talc, provided forms critically‐aligned, through‐going...
[1] We examine the frictional behavior of a range lithified rocks used as analogs for fault rocks, cataclasites and ultracataclasites at seismogenic depths compare them with gouge powders commonly in experimental studies faults. At normal stresses ∼50 MPa, strength lithified, isotropic hard is generally higher than their powdered equivalents, whereas foliated phyllosilicate-rich are weaker gouge, depending on foliation intensity. Most samples exhibit velocity-strengthening behavior, which...
Despite the importance of hydromechanical effects in fault processes, not much is known about interplay chemical and mechanical part because conditions are difficult to simulate laboratory. We report results from an experimental study simulated gouge composed rock salt sheared under where pressure solution operate. At sliding velocities above 10 μ m/s high shear strains (>5), friction measurements show that layers weaken significantly ultimately slide unstably (i.e., stick‐slip)....
Abstract Rate‐and‐state friction (RSF) laws are extensively applied in fault mechanics but have a largely empirical basis reflecting only limited understanding of the underlying physical mechanisms. We recently proposed microphysical model describing frictional behavior granular gouge undergoing deformation terms flow accompanied by thermally activated creep and intergranular sliding at grain contacts. Numerical solutions reproduced typical experimental results well. Here we extend our to...
Research Article| August 01, 2013 Nanocrystalline slip zones in calcite fault gouge show intense crystallographic preferred orientation: Crystal plasticity at sub-seismic rates 18–150 °C Berend A. Verberne; Verberne * 1Department of Earth Sciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, Netherlands *E-mail: B.A.Verberne@uu.nl. Search for other works by this author on: GSW Google Scholar Johannes H.P. de Bresser; Bresser André R. Niemeijer; Niemeijer Christopher J. Spiers;...