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Glacial erosion creates diagnostic landscapes and vast amounts of sediment. However, knowledge about the rate at which glaciers erode and sculpt bedrock and the proportion of quarried (plucked) versus abraded material is limited. To address this, we quantify subglacial erosion rates and constrain the ratio of quarrying to abrasion during a recent, ∼ 200-year long overriding of a bedrock surface fronting, Sermeq Kujalleq (Jakobshavn Isbræ), Greenland, by combining 10 Be analyses, a digital terrain model, and field observations. Cosmogenic 10 Be measurements along a 1.2 m tall quarried bedrock step reveal a triangular wedge of quarried rock. Using individual 10 Be measurements from abraded surfaces across the study area, we derive an average abrasion rate of 0.13 ± 0.08 mm yr -1. By applying this analysis across a ∼ 1.33 km 2 study area, we estimate that the Greenland Ice Sheet quarried 378 ± 45 m 3 and abraded 322 ± 204 m 3 of material at this site. These values result in an average total erosion rate of 0.26 ± 0.16 mm yr -1 , with abrasion and quarrying contributing in roughly equal proportions within uncertainty. Additional cosmogenic 10 Be analysis and surface texture mapping indicate that many lee steps are relicts from the prior glaciation and were not re-quarried during the recent overriding event. These new observations of glacier erosion in a recently exposed landscape provide one of the first direct measurements of quarrying rates and indicate that quarrying accounts for roughly half of the total glacial erosion in representative continental shield lithologies. [ABSTRACT FROM AUTHOR]

The U–Th–Pb age (SIMS) of magmatic (T = 730–744°C) zircon from intermediate and felsic metavolcanics (1923–1926 Ma) of the supracrustal complex in the Kaskama block of the Inari terrane (northwestern part of the Kola–Norwegian region of the Fennoscandian Shield) were obtained for the first time. This makes it possible to attribute these metavolcanics to the Paleoproterozoic Kalevian suprahorizon. The source of primary metarhyodacite and metabasalt in the Kaskama block was the Paleoproterozoic continental lithosphere not younger than 2390–2384 Ma with an essential contribution of juvenile material (εNd(Т) = +1.2...+2.8). The ages of the spatially related tonalites of the Kuroaivi massif (1936 ± 7 Ma, εNd (T) = +0.1) and of the granitoid massifs of the Southern Pechenga zone (1950–1940 Ma) are older, within the errors of the U–Th–Pb age determinations, than the volcanosedimentary deposits of the Kaskama unit and the Vepsian of the South Pechenga zone. This stage of granite formation separates two geodynamic stages in the Kola–Norwegian region of the Fennoscandian Shield: the early continental rifting in the Yatulian–Ludikovian time and a stage similar to the suprasubductional formation setting of the continental lithosphere of the Inari terrane (1926–1850 Ma). [ABSTRACT FROM AUTHOR]

The voluminous Choke Shield basalts and flood basalts are distributed in the central Ethiopian Plateau. They are tholeiitic in composition and have OIB-like geochemical features. The ca. 23 Ma Choke Shield basalts have SiO2 (47.1 wt.%–59.6 wt.%,), MgO (1.01 wt.%–7.8 wt.%,), Na2O + K2O (2.7 wt.%–8.4 wt.%), and display right inclined REE patterns ((La/Yb)N = 21.4–24.2) with enrichment of Nb, Ta, Zr, Hf and Pb in the primitive mantle-normalized trace element diagrams. They show low initial 87Sr/86Sr ratios (0.703 47–0.703 77) and high εNd(t) values (+4.4 to +5.0). In comparison, the 24 Ma high-Ti (HT1) flood basalts have SiO2 (38.9 wt.%–50.8 wt.%), MgO (3.9 wt.%–11.4 wt.%), Na2O + K2O (1.6 wt.%–5.8 wt.%), and display right inclined REE patterns ((La/Yb)N = 24–130.3) with enrichment of Nb, Ta, Zr, Hf, and Pb. They also show low initial 87Sr/86Sr ratios (0.703 30–0.704 44) and high εNd(t) values (+2.2 to +5.3). Both types of basalts were contaminated by minor crustal materials and underwent fractional crystallization of clinopyroxene, plagioclase, olivine, and minor Fe-Ti oxide. The Choke Shield basalts were generated by 1%–5% melting of garnet-spinel to phlogopite-bearing spinel lherzolite in a shallow zone of the mantle plume, while the flood basalts were formed by <20% melting of amphibole-bearing garnet to garnet-spinel lherzolite in a deeper zone of the same mantle plume. The mantle source beneath the central Ethiopian Plateau was significantly heterogeneous during the Tertiary. It was characterized by EMI and EMII end-members that were formed by the metasomatism of the different components. [ABSTRACT FROM AUTHOR]

The resistance transfer coefficient of supports plays an important role in support selection in coal mines, which is the main factor in support crushing accidents. Based on the key layer theory, the formula for calculating the resistance transfer coefficient of supports under the load of a loose layer was deduced. The analysis of four working faces with thick loose layers and the corresponding mining pressure data were used to deduce the load transfer coefficients of the thick loose layers and ultimately illustrate the relationship between thick loose layers and different influencing factors. By using microseismic technology to monitor the process of roof failure in a thin bedrock working face with a thick loose layer during mining, the roof failure characteristics of a large-mining-height working face under the load of a thick loose layer were further verified. The results show that a thicker loose layer and thinner bedrock caused more of the load to transfer to the working face, the roof microseismic events were mainly concentrated in the range of 60 m to 75 m above the coal seam, and the most active events occurred during the square stage (the length of the working face's goaf is equal to its width). The height of the water-conducting fracture zone was analyzed by microseismic data and then verified with theoretical calculations. [ABSTRACT FROM AUTHOR]

Analysis of new detrital apatite fission-track (AFT) ages from modern river sands, published bedrock and detrital AFT ages, and bedrock apatite (U-Th)/He (AHe) ages from the Northern Apennines provides new insights into the spatial and temporal patterns of erosion rates through time across the orogen. The pattern of time-averaged erosion rates derived from AHe ages from the Ligurian side of the orogen illustrates slower erosion rates relative to AFT rates from the Ligurian side and relative to AHe rates from the Adriatic side. These results are corroborated by an analysis of paired AFT and AHe thermochronometer samples, which illustrate that erosion rates have generally increased through time on the Adriatic side but have decreased through time on the Ligurian side. Using an updated kinematic model of an asymmetric orogenic wedge, with imposed erosion rates on the Ligurian side that are a factor of 2 slower relative to the Adriatic side, we demonstrate that cooling ages and maximum burial depths are able to replicate the pattern of measured cooling ages across the orogen and estimates of burial depth from vitrinite reflectance data. These results suggest that horizontal motion is an important component of the overall rock motion in the wedge, and that the asymmetry of the orogen has existed for at least several million years. [ABSTRACT FROM AUTHOR]

Pre-tensioning of rockbolts is permitted to ensure better confinement between bedding rock slopes. The resulting shear adherence between layers is then increased, and a resistance against the rock block's movement is developed. This paper develops a simple analytical approach to better understand the performance of pre-tensioned grouted rockbolts in bedding rock slopes. The force method approach and the deformation compatibility principles are used to model the contribution of developed axial and shear bolt forces at the intersection between the bolt and the joint plane to evaluate the behavior of the rockbolt in the elastic state. The effects of the pre-tension, the joint roughness, bolt inclination with respect to the joint plane, and rock strength are investigated, and the influence of the bolt contribution to preventing rock layer sliding is discussed. Furthermore, a 3D numerical approach is used to study the bolt performance in a plastic state. The results show that when the bolt is completely perpendicular to the discontinuity, the lower bolt contribution is generated. The pre-tensioning and joint roughness caused an improvement in resistance at the joint due to the utilization of the bolt axial capacity. Besides, the pre-tensioned rockbolt will be more useful for high-strength rock slopes. [ABSTRACT FROM AUTHOR]

The Jeokjung-Chogye Basin (JCB) is the first impact crater discovered in the Korean peninsula. The geometric centre of the exterior crater rim is demarcated by an elevation high surrounding the JCB, exceeding 200 m. The diameter of the exterior ring is approximately 6500 m, and its centre is located about 1000 m southwest of the basin centre. Using terrestrial measured gravity field interpretations such as dip curvature and Z -derivative analysis of the residual anomaly field, we calculated the diameters of the peak ring and uplift ring to be about 4000 and 1500 m, respectively. The centre of the peak ring is located approximately 350 m to the west of the centre of the exterior ring; meanwhile, the centre of the uplift ring is located about 300 m to the east from the exterior ring's centre. Application of the Euler deconvolution method indicates that the depth discrepancy between the peak and uplift rings is approximately 200 m. This discrepancy indicates that the bedrock under the uplift ring has risen about 200 m following the meteorite impact. The offsets of the peak and the uplift ring's centres, relative to the diameter of the crater centre, allow us to conclude that the JCB was formed by steeply inclined impact (∼50–60° to the horizontal) from the eastern direction. [ABSTRACT FROM AUTHOR]

"Rock bed" mechanism and its formation were discussed in this article. Inspired by the bionic wear-resistant structure, the shape and parameters of an impact crusher chamber are optimized. Taking both crusher strength and crushing effect into consideration and using discrete element method, the parameters of the impact crusher chamber were properly optimized. By adjusting the major parameters and structures of the factors (rotor speed, angles of the first and second impact plates, shape of impact plate and blow bar material) influencing crushing effect, the orthogonal test with four three-level factors was conducted to find an optimal combination with the best crushing effect so as to optimize the impact crusher. [ABSTRACT FROM AUTHOR]

Roads are generally affected by slope failures, and these failures can increase when there are weathered materials and high rainfall. These circumstances occur in the sub-Andean zone of Ecuador. This is the region where the study area is located. The stability of a stratified rock slope, which is affecting a section of highway E45, was evaluated. The study slope is exposed to the road, but the upper part is covered by a soil-type material and dense vegetation that makes it challenging to study. We applied the Q-slope method and seismic tomography; these methods used together worked well, because they allowed to correlate and infer information about the quality of the rock mass, even in a fast and economical way. We also performed core drilling with core recovery in the crown of the slope and SPT test. The slope presented two well-differentiated zones; therefore, Q-slope values were calculated for each of these zones. The results show that the slope is unstable. The application of seismic tomography as an input parameter for calculating Q-slope was important because it allowed evaluating the stability where it is impossible to collect geomechanical information, correlate information taken at the foot of the slope, and define the depth of the bedrock. [ABSTRACT FROM AUTHOR]

Ground accelerations have been seen to exceed three accelerations of gravity (g). Can extreme motions further surpass this level as more earthquakes are experienced? Also, ground shaking of nearly same severity has been observed near earthquakes differing in magnitude by three units. Does this imply independence of extreme shaking on magnitude? Calculations based on the representation theorem of elasticity verify that maximum ground accelerations on bedrock even for the greatest magnitudes saturate at the level of approximately 3 g. Maximum ground velocities approach the values of 2 m/s. Also, the peak level of extreme shaking is nearly independent of magnitude. [ABSTRACT FROM AUTHOR]

Two specimens of lightfish Vinciguerria sp. were discovered in the rock beds of the middle to late Miocene Kurasi Formation at the south-western coast of the Sakhalin Island, Eastern Russia. A detailed study of their morphology shows that this form cannot be assigned to any known species, although it possesses some similarity with the Oligocene species †V. obscura. Considered together with other Miocene congeners this form demonstrates a high morphological diversity of the Neogene lightfishes. Some aspects of the evolution of the genus during the last 40 M.y. are discussed. [ABSTRACT FROM AUTHOR]

Study aims at selecting the suitable shear modulus reduction and damping curve for broad classification of soil, i.e., rock, gravel, sand, and clay. For this purpose, surface and bedrock ground motion recordings from KiK-Net downhole array for both deep and shallow soil sites have been used. Total stress one-dimensional non-linear site-response analysis has been carried out by varying the available curves for a corresponding soil type. Input parameters for few curves have been determined using parametric study. Linear mixed-effect models on residuals from predicted and recorded surface spectra have been used in suggesting the suitable curve for corresponding soil. [ABSTRACT FROM AUTHOR]

India ranks fifth in the global garment exports. The bedrock of this export industry are poorly paid, migrant women and men. Marked by high rate of exploitation and precarious employment, garment workers are often perceived as a dispossessed lot without any means to resist their exploitation. What possibilities remain within this narrative to make room for everyday politics and resistances? Looking at the individual and collective struggles of garment workers in two southern Indian states, this article highlights the everyday organizing strategies of women resisting their 'disposibility'. Specifically, the article draws attention to women's life stories to demonstrate what can be learnt from them about the conditions under which to imagine, and come to, build labour unions. The article contributes to the critical feminist scholarship on global factories by explicating the tension between the need to illuminate the extent of exploitation and the urgency of drawing attention to women's stories. [ABSTRACT FROM AUTHOR]

This study investigates the spatial and temporal pattern of rock exhumation inboard of the highly oblique Yakutat-North American plate boundary. We aim to quantify how far deformation is transferred inboard of the Fairweather transform plate boundary and across the Eastern Denali fault. We present new detrital apatite and zircon fission track data from 27 modern drainages collected on both sides of the Eastern Denali fault and from the Alsek and Tatshenshini River catchments that drain the mountainous region between the Fairweather fault and the Eastern Denali fault. By integrating our data with published bedrock and detrital geochronology and thermochronology, we show that exhumation reaches much farther inboard (>100 km) of the Fairweather fault than farther north in the St. Elias syntaxial region (<30 km). This suggests that the entire corridor between the Fairweather and Eastern Denali faults exhumed since mid-Miocene time. The Eastern Denali fault appears to be the backstop, and late Cenozoic exhumation northeast of the fault is very limited. [ABSTRACT FROM AUTHOR]

The fragility and sensitivity to climate change of alpine ecosystems make it difficult to maintain the stability of their plant communities. Thus, it is important to determine which plant propagules are stored in the soils in order to understand community recruitment potential, especially under different environmental conditions. Based on a soil seed germination and seedling cultivation experiment, we aimed to identify differences in the soil seed attributes between three typical habitat types in the alpine subnival ecosystems of the Himalaya‐Hengduan Mountains and hence to predict the community recruitment potential of each of these different communities. We found that the seed assemblages in the soils differed between habitats. The most abundant taxa were from the genera Saxifraga, Kobresia, Arenaria, Polygonum, Draba, and Viola, while the taxa with lowest abundance were Apiaceae, Campanulaceae, Circaea, Crassulaceae, and Gentiana. Different habitats exhibited variable soil seed richness, diversity, and density. However, the patterns differed between study sites. Specifically, at Baima (BM) and Shika (SK) snow mountains, soil seed richness, diversity, and density were generally highest in grassland, followed by rock bed and bare ground. In contrast, on Jiaozi (JZ) snow mountain, the rock bed supported the highest soil seed richness and density, followed by grassland and bare ground. These results suggest that the attributes of habitats and communities can both affect the accumulation of soil seeds. Bare ground supports the lowest seed diversity and density but also harbors the most empty niches. We, therefore, predict that, once the thermal conditions become suitable as a result of global warming, this habitat has the potential to see greater changes than grassland and rock bed in terms of community recruitment. [ABSTRACT FROM AUTHOR]

The turbulent plunging jet of a nearly incompressible fluid into a stagnant fluid is of great importance in many practical applications, especially for the engineering of hydropower. As an example, the dynamic load exerted by the impact of turbulent high-velocity jets into a pool must be estimated to evaluate the potential destabilization of a rock bed or dam's structure. Modelling plunging jets in the laboratory presents a challenge due to the complex two-phase environment, which requires models to be built at near-prototype scales. This paper deals with the application of a three-dimensional weakly compressible smoothed particle hydrodynamics (SPH) model to study a circular jet impinging into a water flat pool, at a near-prototype scale. To identify the level of reliability of the computed parameters, validation of the pool bottom pressures is carried out by comparison with existing experimental data. The self-similarity of the jet's centreline velocity is correctly reproduced and the computed maximum dynamic pressures near the stagnation point are reasonably accurate. The differences observed are mainly attributed to the non-consideration of the air phase. [ABSTRACT FROM AUTHOR]

With the aim of unveiling evidence of Late Quaternary faulting, a series of ground-penetrating radar (GPR) profiles were acquired across the southern portion of the Fosso della Valle–Campotenese normal fault (VCT), located at the Campotenese continental basin (Mt. Pollino region) in the southern Apennines active extensional belt (Italy). A set of 49 GPR profiles, traced nearly perpendicular to this normal fault, was acquired using 300 and 500 MHz antennas and carefully processed through a customized workflow. The data interpretation allowed us to reconstruct a pseudo-3D model depicting the boundary between the Mesozoic bedrock and the sedimentary fill of the basin, which were in close proximity to the fault. Once the GPR signature of faulting was reviewed and defined, we interpret near-surface alluvial and colluvial sediments dislocated by a set of conjugate (W- and E-dipping) discontinuities that penetrate inside the underlying Triassic dolostones. Close to the contact between the continental deposits and the bedrock, some buried scarps which offset wedge-shaped deposits are interpreted as coseismic ruptures, subsequently sealed by later deposits. Our pseudo-3D GPR dataset represented a good trade-off between a dense 3D-GPR volume and conventional 2D data, which normally requires a higher degree of subjectivity during the interpretation. We have thus reconstructed a reliable subsurface fault pattern, discriminating master faults and a series of secondary splays. This contribution better characterizes active Quaternary faults in an area which falls within the Pollino seismic gap and is considered prone to severe surface faulting. Our results encourage further research at the study site, whilst we also recommend our workflow for similar regions characterized by high seismic hazard and scarcity of near-surface geophysical data. [ABSTRACT FROM AUTHOR]

Canada and the US The United States and Canada have a long tradition of bilateral and binational security coordination, cooperation and collaboration. This is evident in a vast and growing number of transgovernmental networks that facilitate and enable policy alignment and parallelism in defence, border security, intelligence and counter-terrorism. The security community has mastered coordination and cooperation. The US–Canada relationship is based on reciprocity. Despite its common cultural bedrock though, the US–Canada security community's hallmark is policy parallelism. Forms of mature collaboration remain limited and are only found on occasion. Partnerships have proven more successful in functional areas than in principled ones. [ABSTRACT FROM AUTHOR]

The use of key beds in the cap rocks of the oil reservoirs is crucial. Lack of awareness of these key beds will have serious risks and damages. The Gachsaran oil field is located 220 km southwest of Ahwaz-Iran. The former caprock consists of six key beds (A, B, C, D, E, and F). At the time of writing this paper these key beds are being used during excavations and drilling to determine the site of casing points. What has made utilizing these key beds during excavations difficult however, is use of diamond drill bits which results in the shattering of excavated samples. As such, it has become challenging to learn more about these key beds through studying petrographic thin sections in microscopy. These key beds were observed during the investigation at the drill sites. Later, the excavated samples were studied in the Energy-Dispersive X-ray Spectroscopy (EDS) machine, using a semi-quantitative method to analyze the elemental differences in those key beds. In addition to the identification of various lithological and diagenetic properties of the caprock, this study leads to the introduction of four new key beds based on geochemical properties. Some of the most important differences within the formation include those between the caprock anhydrite and the non-caprock anhydrite, namely the presence of potassium and titanium and the absence of chlorine and sodium in the caprock section. The four new key beds introduced from this study using elemental differences were named as key beds-1, 2, 3, and 4. [ABSTRACT FROM AUTHOR]

Aim: Ground-penetrating radar (GPR) has been used for estimating root biomass, estimating pull-out resistance force of roots, and reconstructing root system architecture. Although GPR can estimate the diameter of a single root, it has not yet been verified whether it can successfully estimate the diameters of adjacent roots or whether rock fragments occurring in the soil matrix can be misidentified as roots. This study aimed to (1) evaluate the visual properties of GPR images of root bundles and rock fragments, and (2) clarify whether they have the potential to create non-negligible errors in GPR surveys. Methods: Root bundle samples buried in a sandy soil bed were scanned using 900 MHz and 1500 MHz antennas. Sole roots of Cryptomeria japonica and rock fragments in the bed were also scanned. Results: A bundle of root formed one hyperbola with an apex in the radar profile, like a sole root. However, the contrast of the hyperbolas was weak and GPR indices relating to diameter were reduced compared to those of the comparably sized sole root. Stones did not form clear images, but boulders were faintly visible with non-negligible GPR indices. Conclusions: For evaluation of root biomass, adjacent roots had the potential to lead to significant errors. Similarly, in reconstructions of root system architecture, adjacent roots might lead to incorrect modelling of root point connections, because of incorrect diameters. For pull-out resistance force, adjacent roots could lead to only underestimation, i.e., safe-side error. Misidentification of rock fragments as roots depends on their sizes. [ABSTRACT FROM AUTHOR]

Ground-penetrating radar (GPR) is widely used for determining mountain glacier thickness. However, this method provides thickness data only along the acquisition lines, and therefore interpolation has to be made between them. Depending on the interpolation strategy, calculated ice volumes can differ and can lack an accurate error estimation. Furthermore, glacial basal topography is often characterized by complex geomorphological features, which can be hard to reproduce using classical interpolation methods, especially when the field data are sparse or when the morphological features are too complex. This study investigates the applicability of multiple-point statistics (MPS) simulations to interpolate glacier bedrock topography using GPR measurements. In 2018, a dense GPR data set was acquired on the Tsanfleuron Glacier (Switzerland). These data were used as the source for a bedrock interpolation. The results obtained with the direct-sampling MPS method are compared against those obtained with kriging and sequential Gaussian simulations (SGSs) on both a synthetic data set – with known reference volume and bedrock topography – and the real data underlying the Tsanfleuron Glacier. Using the MPS modeled bedrock, the ice volume for the Scex Rouge and Tsanfleuron glaciers is estimated to be 113.9 ± 1.6 million cubic meters. The direct-sampling approach, unlike the SGS and kriging, allowed not only an accurate volume estimation but also the generation of a set of realistic bedrock simulations. The complex karstic geomorphological features are reproduced and can be used to significantly improve for example the precision of subglacial flow estimation. [ABSTRACT FROM AUTHOR]

A multi-layer perceptron (MLP) technique is used to train on the response spectra for various strike angles, dip angles, and rake angles. Fixing the magnitude and depth of the earthquakes, the 3-component ground motion is simulated with the help of SPECFEM3D. The residuals of spectral acceleration as a function of time period, for low-rise to high-rise structures, are found to be free of any trend. The hidden layers in the MLP learn the interdependency of focal mechanism parameters on the response spectrum. The resultant model was checked for attenuation characteristics with respect to distance. Furthermore, the trained MLP also showed a shift in spectral peak due to radiation damping, as expected. This MLP architecture presented in this work can be broadly extended to predict the response spectrum, at bedrock level, for any focal mechanism parameters, i.e., strike, dip, and rake, depending on the velocity model of that region. [ABSTRACT FROM AUTHOR]

Kant rejects the ontological argument on the grounds that the ontological argument inescapably must assume that existence is a "determination" or "real predicate," which it is not. Most understand Kant's argument for this claim to be premised upon his distinctive proto-Fregean theory of existence. But this leaves Kant dialectically vulnerable: the defender of the ontological argument can easily reject this as question-begging. I show that Kant relies upon two distinct arguments, both of which contend that the claim that existence is a determination is inconsistent with bedrock ontological set pieces assumed by rationalist defenders of the ontological argument. [ABSTRACT FROM AUTHOR]

We integrated new and existing bedrock and detrital zircon dates from the Zealandia Cordillera to explore the tempo of Phanerozoic arc magmatism along the paleo-Pacific margin of southeast Gondwana. We found that episodic magmatism was dominated by two high-magma-addition-rate (MAR) events spaced ~250 m.y. apart in the Devonian (370-368 Ma) and the Early Cretaceous (129-105 Ma). The intervening interval between high-MAR events was characterized by prolonged, low-MAR activity in a geographically stable location for more than 100 m.y. We found that the two high-MAR events in Zealandia have distinct chemistries (S-type for the Devonian and I-type for the Cretaceous) and are unlikely to have been related by a repeating, cyclical process. Like other well-studied arc systems worldwide, the Zealandia Cordillera high-MAR events were associated with upper-plate deformation; however, the magmatic events were triggered by enhanced asthenospheric mantle melting in two distinct arc-tectonic settings--a retreating slab and an advancing slab, respectively. Our results demonstrate that dynamic changes in the subducting slab were primary controls in triggering mantle flare-up events in the Phanerozoic Zealandia Cordillera. [ABSTRACT FROM AUTHOR]

Essential fish habitats (EFHs) are critical for fish life‐history events, including spawning, breeding, feeding or growth. This study provides evidence of EFHs for the critically endangered flapper skate (Dipturus intermedius) in the waters around the Orkney Isles, Scotland, based on citizen‐science observation data. The habitats of potential egg‐laying sites were parametrised as >20 m depth, with boulders or exposed bedrock, in moderate current flow (0.3–2.8 knots) with low sedimentation. This information provides a significant contribution to the understanding of EFHs for flapper skate. [ABSTRACT FROM AUTHOR]

Based on Biot's theory, the boundary element method, and spectral representation method, an effective simulation method for multiple-station spatially correlated ground motions on both bedrock and surface is developed, incorporating the spectral density function, coherence function, and site transfer function that consider both the wave scattering effect and the medium saturation. The accuracy and feasibility of the present method are validated by a typical numerical example. Our results indicate that the local site conditions and the saturation property of the medium significantly affect the multipoint spatially correlated earthquake ground motions, especially in the long-period range. It is necessary to use spatially varying ground motions with the rational consideration of local site effects and medium saturation as input during the seismic analysis of large-span structures. [ABSTRACT FROM AUTHOR]

From the perspective of a practitioner who was deeply engaged in the negotiations, this article describes how the Israeli-Palestinian Mutual Recognition Agreement was conceived and negotiated. It explains the process of convincing Israeli and Palestinian leaders to accept mutual recognition, overcoming their initial objections. While not nearly as publicized as the 1993 Declaration of Principles agreed at Oslo, this Agreement became the bedrock for all the Oslo Accords, and set the stage for subsequent negotiations. [ABSTRACT FROM AUTHOR]

When interacting with other people, we assume that they have their reasons for what they do and believe, and experience recognizable feelings and emotions. When people act from weakness of will or are otherwise irrational, what they do can still be comprehensible to us, since we know what it is like to fall for temptation and act against one's better judgment. Still, when someone's experiences, feelings and way of thinking is vastly different from our own, understanding them becomes increasingly difficult. Delusions and psychosis are often seen as marking the end of intelligibility. In this article, I argue first for the importance of seeing other people as intelligible as long as this is at all possible. Second, I argue, based on both previous literature and my own lived experience, that more psychotic phenomena than previously thought can be rendered at least somewhat intelligible. Besides bizarre experiences like illusions, hallucinations, and intense feelings of significance, I also explain what it is like to lose one's bedrock, and how this loss impacts which beliefs one has reason to reject. Finally, I give an inside account of some disturbances of reason, and show that there are important similarities between certain psychotic reasoning problems and common non-pathological phenomena. [ABSTRACT FROM AUTHOR]

Verification core holes are important tools in ascertaining the properties of the bed rock at the bottom of drilled shafts. However, it is unknown whether verification core holes fill during concrete placement; if they fill, the mechanical properties of the filling are unknown. The diameters of the core holes are in the 15–30 cm range, and core holes are at least 1.5 m long; empty core holes or core holes filled with weak and deformable materials may significantly decrease the capacity of drill shafts. The paper describes the experiments performed to answer these two questions by using 15- and 30-cm verification core hole models, and drilled shaft depths between 9- and 30-m depth. The smallest slump allowed by the Texas Department of Transportation (TxDOT) was used: 15 and 18 cm in dry and wet conditions, respectively. In dry conditions, verification core holes completely filled with concrete, whose compressive strength exceeded the TxDOT specifications. The compressive strength of the concrete obtained in the 30-cm core holes was higher than the concrete strength in the 15-cm core holes by 60% to 150%. In wet conditions, unless the tremie or pump pipe was inserted into the bottom of the core hole, the bottom half of the verification core filled with uncemented gravel–sand mixture (angle of internal friction, φ=52°), while the upper half of the verification core filled with weakly cemented material whose P-wave velocity was found to be 610 m/s. [ABSTRACT FROM AUTHOR]

Ophiopholis aculeata is a ubiquitous brittle star (Echinodermata: Ophiuroidea) known to occur from the upper subtidal to the bathyal zone. Individuals from shallow inshore habitats (rhodolith beds and rock fields) and deeper offshore locations in eastern Canada were studied to assess the population structure, habitat selection, diet, and feeding strategies of this species through use of stable isotope analyses, gut contents, and laboratory experiments. Potential drivers of habitat selection such as depth, light conditions, body size, sex, intraspecific competition, and presence of predators were examined. This study highlighted variable population size structures and abundances as well as diversified food sources and feeding strategies (i.e., suspension and deposit feeding, scavenging, predation on live organisms, and even cannibalism) as a function of native depth and habitat. It also revealed that studies on the feeding biology of brittle stars must carefully consider sex and life stage as driving factors. [ABSTRACT FROM AUTHOR]

Two early Famennian natural assemblages of conodont elements were found in a marly shale bed within a limestone and shale sequence representing the Palmatolepis triangularis conodont zone at the Kowala quarry in the Holy Cross Mountains, Poland. The most complete of these assemblages, identified as Ctenopolygnathus brevilamina, contained nine skeletally preserved elements and four imprints on the rock bedding plane. A peculiar aspect of the apparatus was the disposition of S4 elements with respect to other S-array elements. Moreover, the denticles of S4 elements were unusually robust and slightly twisted towards the caudal side, which may have resulted from a mode of food processing different from those of other conodonts known from natural assemblages. Moreover, the location of S0 was not consistent with the hypothetical arrangements of similar apparatuses proposed by previous authors. The second assemblage, representing an unidentified palmatolepidid, contained scattered two fragmentary elements and four imprints. [ABSTRACT FROM AUTHOR]

Bedding slope is one of the most common forms of landslides, and determining the shear strength parameters of the sliding surface is essential for the slope stability analysis and engineering design. Due to the different values of shear strength parameters of different sliding surfaces and the existence of the interlayer shear effect during sliding, it is difficult to determine the shear strength parameters of the bedding slope with the multi-layer sliding surface, especially when the multi-layer sliding mass slides at different speeds at the same time. Therefore, the back analysis method combined with the upper-bound limit analysis method with reliability theory is proposed to back-analyze the shear strength parameters of the multi-layer sliding surface simultaneously. By analyzing three practical landslides in detail, the feasibility and applicability of the proposed method are validated. This method enables one to incorporate the effects of uncertainty and randomness of the parameters, and consider the interlayer shear effect, thus obtaining the most likely shear strength parameter combination and providing a reference for the strength parameter back analysis of bedding slopes based on the reliability theory. [ABSTRACT FROM AUTHOR]

Analysis of new detrital apatite fission-track (AFT) ages from modern river sands, published bedrock and detrital AFT ages, and bedrock apatite (U-Th)/He (AHe) ages from the Northern Apennines provide new insights into the spatial and temporal pattern of erosion rates through time across the orogen. The pattern of time-averaged erosion rates derived from AHe ages from the Ligurian side of the orogen illustrates slower erosion rates relative to AFT rates from the Ligurian side and relative to AHe rates from the Adriatic side. These results are corroborated by an analysis of paired AFT and AHe thermochronometer samples, which illustrate that erosion rates have generally increased through time on the Adriatic side, but decreased through time on the Ligurian side. Using an updated kinematic model of an asymmetric orogenic wedge, with imposed erosion rates on the Ligurian side that are a factor of two slower relative to the Adriatic side, we demonstrate that cooling ages and maximum burial depths are able to replicate the pattern of measured cooling ages across the orogen and estimates of burial depth from vitrinite reflectance data. These results suggest that horizontal motion is an important component of the overall rock motion in the wedge, and that the asymmetry of the orogen has existed for at least several million years. [ABSTRACT FROM AUTHOR]

Oxia Planum is a Noachian plain on Mars. It was chosen as the final landing site for in situ studies by ExoMars 2022 rover. The main scientific objectives of the mission are to understand the mineralogy and aqueous evolution of ancient Mars with relevance to habitability. Oxia is covered by vast deposits of Fe,Mg-phyllosilicates, but the exact nature of these deposits is not yet fully understood. We performed a survey of potential terrestrial analog rocks, and here we show combined mineralogical characterization of these rocks with their near-infrared spectral analysis. Samples from two terrestrial sites were studied: (1) vermiculitized chlorite-schists from Otago, New Zealand, which underwent an alteration process without significant oxidation; and (2) basaltic tuffs from Granby, Massachusetts, USA, with Fe-rich clays filling amygdales of supposedly hydrothermal origin. Both analogues are incorporated into the newly built Planetary Terrestrial Analogue Library (PTAL) collection. Oxia bedrock clay-rich deposits are spectrally matched best by a well-crystallized trioctahedral vermiculite/saponite mixture from the basaltic tuff, although the contribution of saponite must be minor. Otago vermiculite is a good analogue to Oxia vermiculite in terms of overall mineralogy and Fe content. However, spectral inconsistencies related to the Al content in the Otago clays indicate that illitization of vermiculite, which results from postalteration oxidation, did not occur at Oxia. This implies limited water/rock interactions and reducing conditions during deposition of sediments now constituting the bedrock at Oxia. Whereas the spectral match does not conclusively imply the mineralogy, trioctahedral vermiculite should be considered a likely mineral component of the bedrock unit at Oxia Planum. Vermiculite has great potential to store organic matter, and the postdeposition geological context of Oxia Planum derived from understanding of environmental conditions in analog sites is promising for organic matter preservation. [ABSTRACT FROM AUTHOR]

Qinghai-Tibet Plateau is one of the most seismically active aeras of China and rock mass structures or geological structure are also complex here. Earthquake-induced geological disasters are occurred frequently in this region. Among them, plane failure is often generated on bedding rock slope especially in destructive area of the Wenchuan earthquake which caused numerous casualties and serious economic loss. To reveal failure mechanism of bedding rock slope, this paper studied the seismic response and investigated progressive failure characteristics of the bedding rock slope through a large-scale shaking table test. A bedding rock slope of 45° contained an unfilled joint set with spacing of 0.1 m that dipped at an angle of 34° out of the surface, was conducted in a rigid model box, with a length of 3.47 m, width of 0.68 m, and height of 1.2 m, respectively. A series of tests results show that acceleration amplification factor in horizontal direction (AAF-X) increases with the increase of the slope elevation and acceleration amplification factor in vertical direction (AAF-Z) amplifies at lower part of the slope. When the shaking intensities are over 0.2 g, the slope crest and its vicinity start to show nonlinear dynamic response. Existence of bedding planes let the isoline morphology of AAF-X redistribute and dominate the seismic amplification at the crest. The progressive failure progress of the model under earthquake can be divided into four stages. This novel experiment offers some important insights to mechanism of bedding plane landslides triggered by earthquakes, evaluation stability of slopes under earthquake, and disaster prevention and mitigation. [ABSTRACT FROM AUTHOR]

The Lesser Himalaya exposed in the Kishtwar Window (KW) of the Kashmir Himalaya exhibits rapid rock uplift and exhumation (∼3 mm yr-1) at least since the late Miocene. However, it has remained unclear if it is still actively deforming. Here, we combine new field, morphometric and structural analyses with dating of geomorphic markers to discuss the spatial pattern of deformation across the window. We found two steep stream segments, one at the core and the other along the western margin of the KW, which strongly suggest ongoing differential uplift and may possibly be linked to either crustal ramps on the Main Himalayan Thrust (MHT) or active surface-breaking faults. High bedrock incision rates (>3 mm yr-1) on Holocene–Pleistocene timescales are deduced from dated strath terraces along the deeply incised Chenab River valley. In contrast, farther downstream on the hanging wall of the MCT, fluvial bedrock incision rates are lower (<0.8 mm yr-1) and are in the range of long-term exhumation rates. Bedrock incision rates largely correlate with previously published thermochronologic data. In summary, our study highlights a structural and tectonic control on landscape evolution over millennial timescales in the Himalaya. [ABSTRACT FROM AUTHOR]

It is commonly accepted that multi-scale structures are subject to spatially variable seismic motions. This spatial variability of seismic motions is described by different intensities at different locations due to the coherency loss effect, wave passage effect and local site conditions. For multi-scale structures, the estimation of seismic excitations must consider these factors. Often, the influence of the spatial variability of seismic motion on the dynamic response of structures is performed by neglecting the site effect. In several cases, it has been observed that the high intensities of seismic motion are caused by the site amplification besides coherency loss and wave passage effects. This study aims to analyze the impact of local site conditions on seismic motions. For this purpose, a method of simulation of spatially variable seismic motions is performed. The seismic signals on the bedrock are defined by considering a target power spectral density and a coherency loss model. According to the seismic wave propagation theory, the projection of these seismic motions on the surface is realized. The results of this study show that neglecting the local site conditions induces an undervaluation of spatially variable seismic excitations. [ABSTRACT FROM AUTHOR]

One of the most important chemical reactions affecting the durability of concrete is the alkali silica reaction (ASR). There are plenty of cherts in many of the quarries in Gümüşhane province. These cherts are used as concrete component together with fine and coarse aggregates obtained by separating from the bedrock by drilling and blasting method. In this study; The cherts (Akçakale, Gümüşhane ve Besyo) taken from 3 different regions of our province of Gümüşhane were brought to the concrete laboratory in our Gümüşhane University. Later, 3 different cherts and reference concrete mixtures taken from different regions were prepared and concrete samples were prepared according to ASTM C 1260 accelerated mortar bar standard. ASR measurements of the mortar samples belonging to the chert mixtures of each region at the end of 3, 7, 14 and 28 days were performed. The results are; it has shown that all samples produced with cherts have a higher length change value than the reference sample, and the length change values increase depending on the curing period. It is observed that 14-day lengthening results exceed the lengthening limit for 0.1 % hazardous aggregates specified in ASTM C 1260 and 28-day lengthening results exceeding the lengthening values of more than 0.2 %. As a result; It was understood that Akçakale, Gümüşhane and Besyo cherts were harmful to ASR considering the curing times of 14 and 28 days. [ABSTRACT FROM AUTHOR]

Large-scale landsliding is an extremely important geological process in shaping landscapes in the Tibetan Plateau. In this research, an ancient river-damming landslide with an estimated debris volume of 4.9 × 107 m3, located in the upper Jinsha River, SE Tibetan Plateau, was studied. The landslide once formed a dam over 60 m high and blocked the river. Lacustrine sediments, composed of silty clay with particle sizes of 0.002–0.25 mm, are intermittently distributed along both banks, extending about 6.5 km upstream. The OSL dating indicates that the lacustrine sediments have an age of 2.6 ± 0.2 ka. Detailed field investigation and theoretical analysis was performed to investigate the characteristics, potential cause and mechanism of the landslide. The results suggest that the landslide was most likely triggered by buckling of planar rock slabs under gravity. It may start as a translational sliding along the weak interlayer composed of mica schist at the upper part of the slope and then formed buckles by curving amphibolite rock beds near the slope toe. The hillslope has still been affected by gravitational deformations, with geomorphology characterized by tension cracks, buckle folds, and small landslide scars distributed on the slope surface, suggesting that the evolution of the river valley caused by buckling deformation has not achieved equilibrium. [ABSTRACT FROM AUTHOR]

Seismic hazard in terms of peak ground acceleration (PGA) and spectral acceleration (SA) for the seismically active Indo-Gangetic Basin (IGB) has been computed using both a fault model and spatially smoothed-grid seismicity model. Seismicity parameters, viz. minimum magnitude, the maximum regional magnitude M max , mean seismic activity rate λ , the slope of the frequency–magnitude Gutenberg–Richter relationship, and the β-value ( b l n (10) ), have been estimated spatially. The layered seismogenic source framework based on hypocentral depth distribution, i.e. 0–25, 25–70, and 70–180 km, for the smoothed-grid seismicity model has also been employed. The lowest λ 4 and λ 5 values for the IGB are 0.05 to 0.02 and 0.015 to 0.005, respectively, in the southern part of the IGB for hypocentral depth variation of 0–25 km. The IGB has a significant variation of seismicity in the entire stretch with noteworthy clustering in the northern side, which gradually decreases towards the south, and the spatial variability of the b-value and M max are 0.65–1.15 and 5.0–8.4 M w , respectively. A ground-motion prediction equation has been selected and weighted by carrying out the efficacy test considering the past earthquakes. The disaggregation process is used for determining the spatial contribution of different magnitudes and distances for the whole IGB. Sensitivity analysis is used for examining the effect of various parameters. The PGA for the IGB varies from 0.06 to 0.54 g for 2% and 0.03 to 0.32 g for a 10% probability of exceedance in 50 years at bedrock condition. The developed average uniform hazard spectra in this study match well with the spectra derived from recorded ground motion. Based on the disaggregation process, dominant magnitude and distance are in the range of 4.7 to 6.0 M w and 15 to 75 km, respectively, in the case of PGA and change to 5.5–7.2 M w and 45 to 150 km in the case of 0.5 s and 5.8–7.5 M w and 70 to 250 km in the case of 2.0 s. Sensitivity analysis suggested that increase in maximum magnitude and distance has an impact on hazard level over a longer period. This is the first time a detailed hazard analysis has been presented for the IGB. [ABSTRACT FROM AUTHOR]

The methods of deriving FeO and TiO2 contents from the Clementine spacecraft data were discussed, and an approach was developed to derive the content from the measurements using the Moon Mineralogy Mapper (M3) instrument on Chandrayaan‐1. The density of lunar bedrock was then modeled on the basis of the derived FeO and TiO2 abundances. The FeO and TiO2 abundances derived from the M3 data were compared with the previous results of the Clementine data and were in good agreement. The FeO abundance data also agreed well with the Lunar Prospector data, which were used as an independent source. The previous Clementine and newly M3 derived abundances were compared with the laboratory measured FeO and TiO2 contents in the Apollo and Luna returned samples. The Clementine derived FeO content was systematically 1%–2% lower than the laboratory measurements in all the returned samples. The M3 derived content agreed well with the returned Apollo samples and was within ±2.8% of the laboratory measurements. The Clementine derived TiO2 abundance was systematically 0.1%–4% higher than the laboratory measurements of the returned samples. The M3 derived TiO2 agreed well (±0.6%) with the laboratory measurements of the returned samples, except for samples with high TiO2 content. However, these results should be carefully interpreted because the error range requires verification. No error analysis was provided with the previous Clementine derived contents. [ABSTRACT FROM AUTHOR]

• Design innovative dates syrup extraction method using solar electro-thermal energy. • Design a hydraulic compression system for squeezing dates to extract syrup (dibs). • The electro-thermal systems are used for heating and circulating dates syrup extraction medium. • The hydraulic compression is used for squeezing dates instead of using traditional weights. • Dates syrup extraction process was catalyzed using a solar water bath and solar air bath. • The extracted dates syrup quality and quantity from different methods were evaluated. The traditional method (TM) of dates syrup (dibs) extraction takes long extraction period and has poor productivity. The TM depends on putting heavyweights above the heap of dates at room temperature, and wait until dibs extraction. This study aims to design two innovative solar electro-thermal energy systems with hydraulic pressure to extract dates syrup. The electro-thermal systems were used to heat and circulate dates dibs extraction medium, while hydraulic pressure (6 ± 1 and 7 ± 1 bar) was used to squeeze dates instead of traditional weights. Solar water bath (SWB) and solar air bath with rocks storage bed (SABWRSB) were used to catalyst the extraction process. The syrup dibs quality and quantity from different methods were evaluated. For innovative methods, the dates temperature inside the extraction tank was about 49–54 °C. The efficiency of the SWB and SABWRSB for syrup extraction was 48.87% and 13.16%, respectively. Using SWB saved time about 38%, and increased the productivity by 28.75% and 36.66% at a pressure of 6 ± 1 and 7 ± 1 bar, respectively, compared to TM. Heating with SWB increased the productivity by 3.6% and 5.68% compared to SABWRSB at 6 ± 1 and 7 ± 1 bar, respectively. The SWB is recommended for providing the appropriate environment for the dates dibs extraction. [ABSTRACT FROM AUTHOR]

When mining under bedding rock slopes, bedding landslides are prone to occur. This paper takes the mining-induced bedding rock landslide as the research area. Using a similar simulation experiment method, the effects of underground adverse slope mining disturbance on deformation, failure, and landslide of bedding rock slope were analyzed. The results show that under the influence of underground mining, the physical models exhibited a cantilever-fracture failure mode. Moreover, the deformation, failure, and landslide of the model were basically the same as the prototype landslide, which was a bedding rock landslide of initial traction type and later pushing type. On this basis, the phenomenon and the coefficient of weakening were defined. The stability of mining-influenced bedding rock slopes was studied by the limit equilibrium method. The outcomes indicate that the fractured block was stable after mining. The fractured block B first slid and came into contact with the fractured block A. The interacting pressure caused the fractured block B to push the fractured block A, and the fractured block A locked the fractured block B. Under the sliding extrusion of the fractured block B, the weakening coefficient of the fractured block A quickly weakened until the fractured block A slid. The fractured block B subsequently slipped after losing the resistance slide of the fractured block A. This successive slip process between the fractured blocks A and B obtained through the stability analysis is consistent with similar simulation experiments. [ABSTRACT FROM AUTHOR]

The potential for widespread landslides is generally increased when extraordinary wet periods occur during times of elevated subsurface hydrologic conditions. A series of storms in early 2018 in Pittsburgh, Pennsylvania, overlapped with a period of increased shallow soil moisture and rising bedrock groundwater levels resulting from seasonally diminished evapotranspiration and induced widespread landslides in the region. Most of the landslides were shallow slope failures in colluvium, landslide deposits, and/or fill. However, deep-seated landslide activity also occurred and corresponded with record cumulative precipitation from late February to April and bedrock groundwater levels rising to an annual high. Landslides blocked or damaged roads, adversely affected multiple houses, disrupted electrical service, crushed vehicles, and resulted in considerable economic losses. The initial landslides occurred during or immediately after a rare period of three successive days of heavy rain that began on February 14. Subsequent landslides between late February and April were induced by multiday storms with smaller rainfall totals. As shallow soil moisture at a monitoring site rose above a volumetric water content of 32%, the mean rainfall intensities necessary to induce slope failure in colluvium and other surficial deposits decreased. Deep-seated landslide movement occurred in the region mostly when the groundwater level in a bedrock observation well was shallower than 1.7 m. The availability of hydrologic and landslide movement monitoring data during this extraordinary series of storms highlighted the evolution of the landslide hazard with changing moisture conditions and yielded insights into potential hydrologic criteria for anticipating future widespread landslides in the region. [ABSTRACT FROM AUTHOR]

The measurement of site amplification of microtremors is an important tool for evaluating seismic hazard at local and regional level. The H/V spectral ratio (HVSR) method is applied to estimate the amplification of ground motion at resonance frequency. The fundamental resonance frequency is estimated at 8 different sites in study region and shows the maximum vulnerability of the site to the earthquakes. This frequency ranges between a minimum of 2.8 Hz to a maximum of 9.3 Hz. The thickness of the sediments below the surface of recording sites is calculated using the empirical relationship that comes out to be in a particular range of 9.5 m–33.1 m above the bed rock. The sedimentary thickness and the resonance frequency clearly matched with geological setting of the study area. The observation shows a slow reduction in the thickness of the sediments and increase in the resonance frequency from South-western part to North-eastern part of the study region. The results show that most of the sites are highly vulnerable to seismic risks with high amplification of seismic waves in the area. Thus, current study provides a deep insight in to the seismic hazard of the Sikkim region with a clear emphasis on the site amplification and the sedimentary cover for the region. [ABSTRACT FROM AUTHOR]

Spatial and temporal coincidence among rapid Pliocene‐Holocene bedrock exhumation, development of a topographic bight, abundant monsoonal precipitation, accumulation of anomalously thick proximal foreland basin deposits, and development of an opposite‐polarity salient‐reentrant couple on the two most frontal major thrust faults in the Himalayan orogenic wedge of central Nepal provide a basis for a model that links these diverse phenomena and could be operating in other parts of the frontal Himalaya. Rapid bedrock erosion is documented by a concentration of young (<5 Ma) low‐temperature thermochronologic ages in the Narayani River catchment basin. Where the river exits the Lesser Himalayan Zone, the Main Boundary thrust has a 15‐km‐amplitude reentrant. Directly south of the reentrant lies the ∼50 km wide Chitwan wedge‐top basin, which is confined by a large salient on the Main Frontal thrust. Rapid erosion and sediment flux out of the Narayani catchment basin, possibly due to anomalously intense monsoonal precipitation in this topographically depressed region of central Nepal, causes greater flexural subsidence and surface aggradation in the foreland, both of which increase initial wedge taper and render this region more susceptible to anomalous forward propagation of the thrust front. Analysis of the modern and post‐early Miocene taper history of the thrust belt suggests that rapid erosion hindered forward propagation of the contemporaneous Main Boundary thrust, but simultaneously produced conditions in the foreland that eventually elevated initial taper to a critical/supercritical value promoting forelandward propagation of the Main Frontal thrust. This analysis has implications for large damaging earthquakes in the Himalaya. Plain Language Summary: The geological history of faulting in the Himalaya is controlled by the distribution of mass in the mountain range and the tectonic forces acting in the ongoing collision between India and Asia. Accordingly, erosion by large rivers, which redistributes mass from the mountain range into the Ganges River basin south of the mountains, may control the locations, shapes, and seismic histories of major Himalayan faults. We show a strong correlation among rapid erosion in central Nepal, extreme precipitation, anomalous sediment deposition in the basin to the south, and peculiarities in the shapes and movement histories of the two largest faults along the southern flank of the range. Our findings have implications for the history of large earthquakes along the front of the Himalaya. In particular, spatial correlations among large erosional basins in the Himalaya, thick sediment accumulations to the south, and abrupt deflections in the shapes of major faults point to enhanced seismic potential along the mountain front. Key Points: A Miocene‐Pliocene erosional bight was rapidly excavated in central Nepal, stalling forward propagation of the Main Boundary thrustSediment from the bight subsequently deposited in the foreland raised initial taper to criticality promoting long‐distance thrust propagationCoincident erosional hotspots, salient‐reentrant couples, and thick foreland sediments suggest future frontal seismic activity [ABSTRACT FROM AUTHOR]

Earthquakes are one of the most significant external factors that induce the failure of anti-dip bedding rock slopes (ABRSs). The pseudo-static method is currently (and is likely to remain in the near future) the most effective and popular method used to evaluate the stability and design of such slopes under the action of earthquakes. In this work, based on the limit equilibrium method and genetic algorithm, a new method considering the inertial force of earthquakes is proposed to assess the stability of ABRSs. Results previously obtained from centrifuge tests and reported in the literature were used to investigate the veracity of the proposed method. A parametric study was then performed to investigate the effects of earthquakes and the mechanical properties of the rock layers on the failure mechanism of an ABRS. The results show that ABRSs are more likely to undergo a complex combination of shearing and flexural toppling failure under the combined action of gravity and earthquake. The direction of the earthquake-induced inertial force, tensile strength of the rock layers, and shear strength of the joints significantly affect the stability of ABRSs. On the other hand, these factors have little influence on the shape of the failure surface. The failure surface is stepped (with steps of different heights) rather than a plane. The failure surface and corresponding safety factor of an ABRS can be readily found using the proposed method, and the failure mode of each rock layer can be obtained. The method proposed in this work provides a convenient theoretical tool for the design of ABRSs in regions prone to seismic activity. [ABSTRACT FROM AUTHOR]

Dendritic, i.e., tree-like, river networks are ubiquitous features on Earth's landscapes; however, how and why river networks organize themselves into this form are incompletely understood. A branching pattern has been argued to be an optimal state. Therefore, we should expect models of river evolution to drastically reorganize (suboptimal) purely nondendritic networks into (more optimal) dendritic networks. To date, current physically based models of river basin evolution are incapable of achieving this result without substantial allogenic forcing. Here, we present a model that does indeed accomplish massive drainage reorganization. The key feature in our model is basin-wide lateral incision of bedrock channels. The addition of this submodel allows for channels to laterally migrate, which generates river capture events and drainage migration. An important factor in the model that dictates the rate and frequency of drainage network reorganization is the ratio of two parameters, the lateral and vertical rock erodibility constants. In addition, our model is unique from others because its simulations approach a dynamic steady state. At a dynamic steady state, drainage networks persistently reorganize instead of approaching a stable configuration. Our model results suggest that lateral bedrock incision processes can drive major drainage reorganization and explain apparent long-lived transience in landscapes on Earth. [ABSTRACT FROM AUTHOR]

Topography effects on the vertical vibration responses of pile group are revealed though numerical analysis and model tests. First, a series of model tests with different topography of ground and bedrock are conducted. The results indicate that displacement amplitude of the pile head in sloping ground topography is larger than in horizontal ground. Differential displacement at various positions of the pile cap is observed in non-horizontal topography. Afterwards, a numerical algorithm is employed to further explore the essential response characteristics in group piles of different topography configurations, which has been verified by the test results. The lengths of the exposed and frictional segment, together with the thickness of the subsoil layer, are the dominant factors which cause non-axisymmetric vibration at the pile cap. [ABSTRACT FROM AUTHOR]