... to understand the impacts. Eight autoclave experiments reacting Marcellus and Eagle Ford Shale samples with synthetic brines and a friction reducer were conducted for more than 21 days. To better determine mineral dissolution and precipitation at the rock–water interface, the shale samples were ion milled...

...B. Proctor; D.A. Lockner AbstractSolidified frictional melts, or pseudotachylytes, are observed in exhumed faults from across the seismogenic zone. These unique fault rocks, and many experimental studies, suggest that frictional melting can be an important process during earthquakes. However...

...Thomas M. Mitchell; Virginia Toy; Giulio Di Toro; Jörg Renner; Richard H. Sibson AbstractDuring earthquakes, melt produced by frictional heating can accumulate on slip surfaces and dramatically weaken faults by melt lubrication. Once seismic slip slows and arrests, the melt cools and solidifies...

... of the Sudbury breccia: (1) in situ frictional or shock melting of target rocks, (2) cataclasis of the target rocks, and/or (3) injection of allochthonous impact melt from the Sudbury Igneous Complex into the brecciated crater floor. This study reports new mineralogical and geochemical data for samples...

... that the intermediate principal stress is equal to the mean stress and then average the results for hydrostatic pore pressure and dry conditions. The details of the estimate are in the Appendix . The effective normal stress is 122 MPa resulting in an initial stress of τ 0 =104  MPa for a Byerlee friction of 0.85...

... is that the shear modulus of the rock self‐organizes so that the rock barely fails in friction with typical imposed dynamic strains. The predicted value of stiffness divided by depth is then independent of depth for constant rock density and constant coefficient of friction with the water table at the surface...

...Francesco Fidolini; Massimiliano Ghinassi Abstract: Sediment transport and deposition at river-dominated river mouths are controlled by: i) outflow inertia, ii) turbulent bed friction, or iii) outflow buoyancy. In mouth-bar-type deltas, which typically form in shallow-water settings, friction...

...Norman H. Sleep; Nori Nakata AbstractStrong Rayleigh waves are expected to bring the shallow subsurface into frictional failure. They may nonlinearly interact with high‐frequency S waves. The widely applied Drucker and Prager (1952) rheology predicts that horizontal compression half‐cycle...

... Friction coefficient 0.85 0.73 0.85 Cohesion (MPa) 10–20 1.4 × 10 −4 1.4–2.8 × 10 −5 Non-dimensional shear strength ratio, ρlg/τ 0 0.38–0.76 0.1 0.1–0.3 Strike-slip fault systems commonly show an anastomosing array of contemporaneous faults including rhomb-shaped pull-apart...

... in a relatively strong crust (basement) and filled with weak syn-rift sediments (cover). We investigate the relative influence of the internal friction (µ) of the basin-bounding normal fault, tectonic burial (h) under an overlying nappe and the geothermal gradient. We use...

...Naoyuki Kato AbstractNumerical simulations of complex earthquake cycles are conducted using a model with two patches (asperities) on a fault, where friction obeys a rate‐and‐state‐dependent law. The patches are represented by regions of steady‐state velocity‐weakening friction and are in contact...

... are made of glass, resulting in a model with a relatively high basal friction. Side walls are not lubricated during experimental runs, as the model apparatus is sufficiently wide to obtain results in the centre of the apparatus which are free from edge effects. An empirical rule...

... hypocentral area. This unusual phenomenon may have provided a second breath to the rupture that enhanced its final size. Here, we propose that rupture reactivation may have been governed by a slip‐weakening friction model with two sequential strength drops, the second one being activated at large slip...

...Eric C. Ferré; En-Chao Yeh; Yu-Min Chou; Ruo Lin Kuo; Hao-Tsu Chu; Caitlyn S. Korren AbstractStriations along fault planes, such as slickensides, generally indicate slip direction. These linear structures typically form through friction between two solids. Here we describe brushlines, a new class...

..., to illuminate the fine‐scale details of the seismicity distribution near Cholame and the relation to the distribution of LFEs. The depth of the boundary between earthquakes and LFE hypocenters changes along strike and roughly follows the 350°C isotherm, suggesting frictional behavior may be, in part, thermally...

... (décollements). The increase of temperature with depth along clay-rich faults promotes the so-called smectite-illite transition, which may influence the fault strength, fluid distribution, and possibly the onset of seismicity. Here we report on the frictional properties of intact fault rocks retrieved from two...

... that is incorporated into the slip zone that was drilled during the Japan Trench Fast Drilling Project (JFAST) Expedition 343 in the Japan Trench, located ∼820 m below seafloor. This study investigates the potential for abundant smectite to preserve a record of coseismic frictional heating associated with the Tohoku...

...-angle normal faults cutting carbonates in the Southern Apennines of Italy show that slip was promoted by two weakening mechanisms producing a reduction of the friction coefficient: (1) high pore fluid pressures; (2) dynamic weakening related to thermal decomposition indicated by decarbonation...

... and the quality of the resulting conductive reservoir area are primarily functions of the natural fracture network characteristics (e.g., spacing, height, length, number of fracture sets, orientation, and frictional properties); in situ stress state (e.g., stress anisotropy and magnitude); stimulation design...