Graben formation and dike arrest during the 2009 Harrat Lunayyir dike intrusion in Saudi Arabia: Insights from InSAR, stress calculations and analog experiments

Detailed spatial and temporal accounts of propagating dikes from crustal deformation data, including their interplay with faulting, are rare, leaving many questions about how this interplay affects graben formation and the arrest of dikes unanswered. Here we use interferometric synthetic aperture radar (InSAR) observations, stress calculations, and analog experiments to investigate the interaction between an intruding dike and normal faulting during the 2009 Harrat Lunayyir dike intrusion in western Saudi Arabia. We generated five displacement maps from InSAR data to unravel the temporal evolution of deformation covering the majority of the intrusion. We find that the observed surface displacements can be modeled by a ~2 m thick dike with an upper tip ~2\u2009km below the surface on 16 May 2009, 4\u2009weeks after the onset of seismic unrest. In the following three days, the dike propagated to within ~1\u2009km of the surface with graben\u2010bounding normal faulting dominating the near\u2010field deformation. The volume of the dike doubled between mid\u2010May and mid\u2010June. We carried out analog experiments that indicate that the wedge\u2010shaped graben grew outward with the faulting style changing progressively from normal faulting to oblique. Coulomb failure stress change calculations show that the intruding dike caused two zones of shallow horizontal tension on both sides of the dike, producing two zones of fissuring and normal faulting at the surface. In return, the faulting provoked compression around the upper tip of the dike, holding back its vertical propagation

Available raw data collected in the Simbruini-Ernici Ridge and discussed in the paper: Shallow deformation in subduction zones: microstructural evidence for aseismic slip and low frequency tremor in molasse-type conglomerates from the Central Apennines accretionary wedge

This file contains uninterpreted geological data collected in the Simbruini-Ernici Ridge such as field photos, microphotos and SEM photos, along with coordinates of sampling localities and main structural data. Data are made available for supporting the paper: Shallow deformation in subduction zones: microstructural evidence for aseismic slip and low frequency tremor in molasse-type conglomerates from the Central Apennines accretionary wedg

Pupillary effects in habitual cannabis consumers quantified with pupillography

Driving under the influence of alcohol (DUIA) and drugs (DUID) is considered an elevated risk for traffic safety. When assessing a driver's fitness to drive, standardized and objective measurement methods are still required, in order to clarify the question whether an individual is under the influence of substances acting on the central nervous system (CNS). We exposed healthy test subjects (n=41) as well as persons who were under the influence of cannabis after repeated inhalation to multiple light stimuli using infrared technology and measured the pupillary light reflex (PLR). Toxicological tests of blood samples taken from every subject followed. The aims of this study were to assess the differences in pupillography response between cannabis consumers after a washout period and no cannabis consumers as well as the dose related effects on pupillography parameters of cannabis in cannabis consumers. All four pupillary parameters changed according to a weakened pupil function after acute administration of cannabis in all test subjects. Furthermore, it could be observed that habitual cannabis consumers showed an altered pupillary function just before the first dose was taken, suggesting that the long-term effects and addiction also have to be taken into account, when effects of the CNS are discussed. The results of the present study show that almost all pupil parameters could be reliable indicators for the detection of subjects under the acute effect of cannabis

Empirical Analysis of Global-Scale Natural Data and Analogue Seismotectonic Modelling Data to Unravel the Seismic Behaviour of the Subduction Megathrust

Subduction megathrusts host the Earth’s greatest earthquakes as the 1960 Valdivia (Mw9.5, Chile), the largest earthquake instrumentally recorded, and the recent 2004 Sumatra-Andaman (Mw9.2, Indonesia), 2010 Maule (Mw8.8, Chile), and 2011 Tohoku-Oki (Mw9.1,Japan) earthquakes triggering devastating tsunamis and representing a major hazard tosociety. Unravelling the spatio-temporal pattern of these events is thus a key for seismichazard assessment of subduction zones. This paper reviews the current state ofknowledge of two research areas–empirical analysis of global-scale natural data andexperimental data from an analogue seismotectonic modelling—devoted to study cause-effect relationships between subduction zone parameters and the megathrustseismogenic behavior. The combination of the two approaches overcomes theobservational bias and inherent sampling limitations of geological processes(i.e., shortness of instrumental and historical data, decreasing completeness andresolution with time into the past) and allows drawing appropriately from multipledisciplines with the aim of highlighting the geodynamic conditions that may favor theoccurrence of giant megathrust earthquakes

Transnational Access to Research Facilities: an EPOS service to promote multi-domain Solid Earth Sciences in Europe

Transnational access (TNA) allows cross-border, short-term and frequently free-of-charge access to world-class research facilities, to foster collaborations and exchanges of experience. Specifically, TNA aims to encourage open science and innovation and to increase the efficient and effective use of scientific infrastructure. Within EPOS, the European Plate Observing System, the Volcano Observatories and Multi-scale Laboratories communities have offered TNA to their high-quality research facilities through national and European funding. This experience has allowed the definition, design, and testing of procedures and activities needed to provide transnational access inn the EPOS context. In this paper, the EPOS community describes the main objectives for the provision of transnational access in the EPOS framework, based on previous experiences. It includes practical procedures for managing transnational access from a legal, governance, and financial perspective, and proposes logistical and technical solutions to effectively execute transnational access activities. In addition, it provides an outlook on the inclusion of new thematic communities within the TNA framework, and addresses the challenges of providing market-driven access to industry.publishedVersio

Simulating land use changes, sediment yields, and pesticide use in the Upper Paraguay River Basin: Implications for conservation of the Pantanal wetland

As a consequence of accelerated and excessive use of pesticides in tropical regions, wilderness areas are under threat; this includes the Pantanal wetlands in the Upper Paraguay River Basin (UPRB). Using a Land Cover Land Use Change (LCLUC) modelling approach, we estimated the expected pesticide load in the Pantanal and the surrounding highlands region for 2050 under three potential scenarios: i) business as usual (BAU), ii) acceleration of anthropogenic changes (ACC), and iii) use of buffer zones around protected areas (BPA). The quantity of pesticides used in the UPRB is predicted to vary depending on the scenario, from an overall increase by as much as 7.4% in the UPRB in the BAU scenario (increasing by 38.5% in the floodplain and 6.6% in the highlands), to an increase of 11.2% in the UPRB (over current use) under the AAC scenario (increasing by 53.8% in the floodplain and 7.5% in the highlands). Much higher usage of pesticides is predicted in sub-basins with greater agricultural areas within major hydrographic basins. Changing the current trajectory of land management in the UPRB is a complex challenge. It will require a substantial shift from current practices, and will involve the implementation of a number of strategies, ranging from the development of new technologies to achieve changes in land use policies, to increasing dialogue between farmers, ranchers, the scientific community, and local or traditional communities through participatory learning processes and outreach

Aseismic transient driving the swarm-like seismic sequence in the Pollino range, Southern Italy

Tectonic earthquake swarms challenge our understanding of earthquake processes since it is difficult to link observations to the underlying physical mechanisms and to assess the hazard they pose. Transient forcing is thought to initiate and drive the spatio-temporal release of energy during swarms. The nature of the transient forcing may vary across sequences and range from aseismic creeping or transient slip to diffusion of pore pressure pulses to fluid redistribution and migration within the seismogenic crust. Distinguishing between such forcing mechanisms may be critical to reduce epistemic uncertainties in the assessment of hazard due to seismic swarms, because it can provide information on the frequency–magnitude distribution of the earthquakes (often deviating from the assumed Gutenberg–Richter relation) and on the expected source parameters influencing the ground motion (for example the stress drop). Here we study the ongoing Pollino range (Southern Italy) seismic swarm, a long-lasting seismic sequence with more than five thousand events recorded and located since October 2010. The two largest shocks (magnitude Mw = 4.2 and Mw = 5.1) are among the largest earthquakes ever recorded in an area which represents a seismic gap in the Italian historical earthquake catalogue. We investigate the geometrical, mechanical and statistical characteristics of the largest earthquakes and of the entire swarm. We calculate the focal mechanisms of the Ml > 3 events in the sequence and the transfer of Coulomb stress on nearby known faults and analyse the statistics of the earthquake catalogue. We find that only 25 per cent of the earthquakes in the sequence can be explained as aftershocks, and the remaining 75 per cent may be attributed to a transient forcing. The b-values change in time throughout the sequence, with low b-values correlated with the period of highest rate of activity and with the occurrence of the largest shock. In the light of recent studies on the palaeoseismic and historical activity in the Pollino area, we identify two scenarios consistent with the observations and our analysis: This and past seismic swarms may have been ‘passive’ features, with small fault patches failing on largely locked faults, or may have been accompanied by an ‘active’, largely aseismic, release of a large portion of the accumulated tectonic strain. Those scenarios have very different implications for the seismic hazard of the area

Emotional intelligence training intervention among trainee teachers: a quasi-experimental study

Background: Emotional intelligence (EI) has often been linked to improvements in professional performance. Indeed, generic competencies related to EI have been included in university curricula. However, learning EI involves significant time and effort on the part of students, and this may hinder the acquisition of specific content for each degree. In this study, an intervention to develop EI in higher education students is described and evaluated. Methods: The intervention consisted of eight group sessions performed in a regular course aiming to increase EI. The sessions included strategies and training on perceiving and understanding one’s own emotions and others’ emotions, identifying and understanding the impact one’s own feelings in adopting decisions, expressing one’s own emotions and the stress experienced, and managing both one’s own emotions and emotions of others. Participants were 192 students studying for a Master of Primary Education degree. A quasi-experimental nonequivalent control group pretest-posttest design was adopted. The effectiveness of the intervention was evaluated using multi-level analyses. Results: The results showed a significant improvement in the EI of students in the experimental group compared with the control group. Conclusions: This research demonstrates that it is possible to develop EI in higher education students, without hindering the acquisition of specific content competencies and, therefore, without interfering with their academic performance and without overburdening students with work outside the classroom. Trial registration: The experiment has been registered in the Initial Deposit of the Spanish Center for Sociological Research (CIS). 7/6/2015. http://www.cis.es/cis/opencms/ES/index.html.This research was supported by the Spanish Ministry of Economy and Competitiveness under Grant number EDU2015-64562-R

Coupling at plate boundaries : insights from laboratory experiments

The aim of this Thesis is to study the role of interplate frictional properties on boundary shaping and seismicity associated with subduction zones. This is achieved by means of a multidisciplinary approach, combining two different scales of analogue models, rheometry and worldwide statistics of subduction-related thrust-type earthquakes. Concerning the key problem of long-term frictional resistance to subduction, I relate the peculiar shape observed along Andes at present-day and associated topography to lateral variation in mechanical coupling. Frictional processes acting along the subduction thrust fault play also an important role also on shorter timescale with effect on seismicity. The strategy of the adopted approach is to formulate the simplest setup allowing systematically the separation between different effects. The Andean belt is the result of a favorable combination of plate kinematic parameters. While the Nazca plate, driven by negative buoyancy, undergoes weakened continental South America, mechanical coupling between converging plates is resisting to this motion. The development of trench curvature, shortening of the overriding plate, and topography could be related to lateral variation of the degree of mechanical coupling between converging plates. Here I use laboratory models of subduction in order to qualitatively test this hypothesis (Chapter 3). Most of the global seismic energy is released by discontinuous shear of the frictional interface between the subducting and the overriding plate. First-order importance in controlling the seismic variability of subduction zones is recently attributed to interface roughness (including amount of sediments) and subduction velocity. Here I present a set of spring block-like models, which is known to mimic the seismic behavior, with the aim to explore the role played by the contact roughness, sliding velocity and normal load in friction dynamics (Chapter 5). The experimental setup consists of a viscoelastic gelatin slider - analog of the Earth's crust - moving on sandpaper, a small scale rough interface representative of the interplate contact. These experimental results, combined with worldwide seismic observables, offer the possibility of reconciling within a single model where contact interface is evolving during plate subduction the occurrence of creepingvelocity strengthening and seismic-velocity weakening regions along the subduction thrust plane. This work is supported by a preliminary systematic study of both rheological and physical properties of a wide range of gelatins (Chapter 4) which helped in selecting the right material (pig skin 2.5 wt.% at 10 °C) for a suitable experimental set-up to downscale model for subduction interplate seismicity. I use both tribological and rheological background to built a realistic (wedge shaped) analogue model of subduction thrust-type earthquakes and rupture dynamics including rate- and state- friction and viscoelastic deformation (Chapter 6)