Psychosocial research and action with survivors of political violence in Latin America: methodological considerations and implications for practice.

Research with survivors of political violence in Latin America have shown that any analysis of the consequences of war or political repression should take into account the social and political realities in which the survivors are immersed. It has also shown that research must go hand in hand with action, intervention and psychosocial support for communities that confront violence. In this article, the authors review some of the basic principles that should guide research and action within the context of war or other political violence. We discuss the roles that the researcher needs to adopt in order to successfully develop work that will be of use to the social and scienti¢c community. In addition, we describe some of the methodological implications of psychosocial research and the importance of re£ective processes that could contrib- ute to community wellbeing. The theoretical descriptions are substantiated through examples of action research in Jujuy (Argentina) with for- mer political prisoners and relatives of detainees, or the disappeared, from the time of the last mili- tary dictatorship (1976^1983)

Volcanic signatures in time gravity variations during the volcanic unrest on El Hierro (Canary Islands)

Gravity changes occurring during the initial stage of the 2011–2012 El Hierro submarine eruption are interpreted in terms of the pre-eruptive signatures during the episode of unrest. Continuous gravity measurements were made at two sites on the island using the relative spring gravimeter LCR gPhone-054. On September 15, 2011, an observed gravity decrease of 45 μGal, associated with the southward migration of seismic epicenters, is consistent with a lateral magma migration occurred beneath the volcanic edifice, an apparently clear precursor of the eruption that took place 25 days later on October 10, 2011. High-frequency gravity signals also appeared on October 6–11, 2011, point to an interaction between a magmatic intrusion and the ocean floor was occurring. These important gravity changes, with amplitudes varying from 10 to −90 μGal, during the first three days following the onset of the eruption are consistent with the northward migration of the eruptive focus along an active eruptive fissure. An apparent correlation of gravity variations with body tide vertical strain was also noted, which could indicate that concurrent tidal triggering occurred during the initial stage of the eruption.Projects CGL2011-25494 and CGL2011-16144-E of the Spanish Ministry of Economy and Competitiveness and European Commission VULMAC-MAC/2.3/A7 (INTERREG) and VUELCO (FT7 Theme: ENV.2011.1.3.3-1; Grant 282759)Peer reviewe

Ocean loading effects from tidal tilt observations in Lanzarote Island

Comunicación presntada a la 3ª Asamblea Hispano-Portuguesa de Geodesia y Geofísica = 3ª Assembleia Luso-Espanhola de Geodesia e Geofisica, celebrada en Valencia entre el 4 y el 8 de febrero de 2002.Since 1995 two short base-length horizontal pendulums are continuously recording at the station Cueva de los Verdes (Geodynamics laboratory of Lanzarote). Both tilt-meters are modified from the classical Ostrovsky pendulums and are adapted to the local features of the station. The tilt-meters have a working range of measurements of +-20seconds of arc and can resolve up to one second of arc. Such technical properties allow determining the precise tilt response to Earth tides. The tidal tilt models obtained show an important influence from ocean tides. Thus, the estimated amplitude for the main harmonic constituents is of some 4-5 times larger than values measured at continental stations. In this work, the ocean loading and attraction effect, which are computed from global ocean tidal models supplemented with precise regional and local ones will be evaluated. Hence, tidal tilt observations can be corrected from this effect.Peer reviewe

Analysis of tidal strain observations in Lanzarote Island

Comunicación presntada a la 3ª Asamblea Hispano-Portuguesa de Geodesia y Geofísica = 3ª Assembleia Luso-Espanhola de Geodesia e Geofisica, celebrada en Valencia entre el 4 y el 8 de febrero de 2002.The strain response of the Earth to tidal forces is observed in the Geodynamics Laboratory of Lanzarote Island. The instruments, installed in a gallery inside the lava tunnel of Cueva de los Verdes, are kind of horizontal ceramic-tube extensometers. Their base fines comprise from 8 to 38 m length and are orientated in two orthogonal directions (45º.2 N Y 135°.2 N), which depend on the situation in the gallery. The reliability of this instruments, which measure the variation of distance between two fixed points with a resolution of 10 -10, allow us to dispose long term series of tidal strains since 1992. The data series are analysed in order to study the stability of the instruments. Also, with these data we can determine the tidal strain models, as well as the tidal deformation and the long-term variations of strains in this island. Due to the dependence of the local conditions of the station, which is located in an island, the oceanic influence will be investigated together with local atmospheric disturbing effects. These effects are carefully studied for this station, in order to allow the identification and, if possible, its separation from other signals of interest, given the volcanic feature of the island.Peer reviewe

APARECIDA, UM SANTUÁRIO QUE DÁ QUE PENSAR: ANÁLISE NO HORIZONTE DO REALISMO ZUBIRIANO

O Santuário de Aparecida é até hoje o maior santuário mariano do mundo. Como espaço sagrado tem um diferencial que o torna paradigma e espelho do Concílio Vaticano II. Neste artigo vamos desenvolver uma análise do Santuário, que poderia ser no pensamento do filósofo contemporâneo Xavier Zubiri, uma realidade que dá que pensar. Significa que busca na marcha da razão a realidade-fundamento de Aparecida, na dimensão artística da arte litúrgica sacra de Claudio Pastro, que recobre toda a parte interna. Se é assim, todo romeiro que por aí passa volta para casa envolvido no Mistério Pascal, em uma busca inquirente de realidade em profundidade. É no detalhe do painel dos homens da evangelização do Brasil, que demonstraremos como o Santuário de Aparecida dá que pensar

Characterization of volcanic structures using ground penetrating radar and additional inverse modelling: Multidisciplinary geophysical investigation in the Timanfaya National Park (Spain)

—A ground penetrating radar survey is presented over a recent lava flow at the volcanic area of Timanfaya National Park (Canary Island, Spain). The purpose was to locate lava tubes into the lava flow through the combination of field and simulated data. Different modelling strategies were used for the analysis and knowledge of the signal behaviour. Finite-difference time-domain algorithm was considered for simulations, and the pattern of reflections generated from previously known volcanic structures were characterized. After the characterization of the radar-wave response, the interpretation achieved was applied over the field data acquired at other non-studied area in which different lava tubes were recognized.Authors thanks to the financial support of the National Parks Network of the Spanish Ministry of Environment and Rural and Marine Affairs (320/2011 – project “Caracterización estructural del Parque Nacional de Timanfaya mediante uso combinado de técnicas y métodos geodésicos y geofísicos”. The staff of National Park of Timanfaya is also acknowledged, as well as the Applied Geotechnologies research group from the University of Vigo for providing the RAMAC/GPR equipment. Additionally, this study is a contribution to the EU funded COST Action TU-1208.Peer reviewe

Three‐Dimensional Magnetic Models of La Gomera (Canary Islands): Insights Into the Early Evolution of an Ocean Island Volcano

An aeromagnetic data set from the island of La Gomera was studied through two inverse modeling approaches that produced complementary views of the inner structure of this volcanic island: (1) a variable magnetization model that identified the main lateral magnetization contrasts and (2) a constant magnetization model that imaged the main magnetic source by assuming that it was a uniformly magnetized body. The modeling reveals intense magnetizations beneath the northern part of La Gomera, which occupy an important portion of the northern submarine edifice, correspond well with outcrops of the submarine volcano (Basal Complex), and confirm that most of the magnetic signal revealed by aeromagnetic mapping in the Canary Islands is due to the intense magnetizations of the intrusive complexes (plutonic bodies and dike complexes) emplaced during the initial stages of growth of the volcanic edifices. The consistency of our models with the results of a previous gravimetric study suggests that these intrusive complexes are denser and more magnetic than the surrounding rocks. The location of the main magnetic source reinforces the interpretation, first suggested by geological evidence, that the submarine and early subaerial growth of La Gomera started to the north of the present island. The elongated shape of these intrusive complexes with a nearly E-W strike agrees with the orientation of analogous structures on Tenerife and Gran Canaria, suggesting that the initial formation of the central islands of the Canary Archipelago was controlled by a set of regional fractures in a strike-slip tectonic framework.Spanish Ministry of Science, Innovation and Universities (Project CGL2015-63799-P) and by the Junta de Castilla y León and the European Regional Development Fund (ERD) (Project BU235P18)

Imaging Thermal Anomalies in Hot Dry Rock Geothermal Systems from Near-Surface Geophysical Modelling

Convective hydrothermal systems have been extensively studied using electrical and electromagnetic methods given the strong correlation between low conductivity anomalies associated with hydrothermal brines and high temperature areas. However, studies addressing the application of similar geophysical methods to hot dry rock geothermal systems are very limited in the literature. The Timanfaya volcanic area, located on Lanzarote Island (Canary Islands), comprises one of these hot dry rock systems, where ground temperatures ranging from 250 to 605 ◦C have been recorded in pyroclastic deposits at shallow (<70m) depths. With the aim of characterizing the geophysical signature of the high ground temperature areas, three different geophysical techniques (ground penetrating radar, electromagnetic induction and magnetic prospecting) were applied in a well-known geothermal area located inside Timanfaya National Park. The area with the highest ground temperatures was correlated with the location that exhibited strong ground penetrating radar reflections, high resistivity values and low magnetic anomalies. Moreover, the high ground temperature imaging results depicted a shallow, bowl-shaped body that narrowed and deepened vertically to a depth greater than 45 m. The ground penetrating radar survey was repeated three years later and exhibited subtle variations of the signal reflection patterns, or signatures, suggesting a certain temporal variation of the ground temperature. By identifying similar areas with the same geophysical signature, up to four additional geothermal areas were revealed. We conclude that the combined use of ground penetrating radar, electromagnetic induction and magnetic methods constitutes a valuable tool to locate and study both the geometry at depth and seasonal variability of geothermal areas associated with hot dry rock systems

Imaging the volcanic structures beneath Gran Canaria Island using new gravity data

From a new gravity data set that covers homogeneously the whole surface of Gran Canaria (Canary Islands, Spain) and marine gravity data in the nearest offshore, we have obtained a Bouguer anomaly gravity map of the island which improves the previous ones. Using these gravity anomalies, we have applied a gravity inversion approach to investigate the structures beneath the surface of Gran Canaria Island and derive a 3D gravity sources model. The geometry of structures with anomalous density values is constrained up to a depth of approximately 20,000 m below the sea level. The interpretation of the density model identified structures related to the different volcanic stages of Gran Canaria. Several deep-rooted high-density structures represent the intrusive bodies emplaced in the early formation of Gran Canaria and the magma plumbing system of the Miocene volcanic edifices. A low-density body in the center of the island may be associated with the syenitic core of the felsic central volcanic edifice (Tejeda Caldera). Shallow low-density structures identified fractures which acted as feeder dikes of monogenetic volcanoes during the rejuvenated stage. Finally, the NW-SE rift, which is the most important volcano-tectonic structure of Gran Canaria, has a characteristic gravimetric signature and represents a long-lived extensional fracture zone that has controlled the volcanic activity at least since the Miocene