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The Guadalentin Depression is bordered by an active left-lateral strike-slip fracture system, which serves as the corresponding tectonic boundary. This depression is a significant elongated Plio-Quaternary basin located within the deformation corridor of the Eastern Betic Shear Zone (EBSZ), trending in a NE-SW direction. Stretching for about 100 km, the western margin of the basin is characterized by a prominent mountain front mainly controlled by the Alhama de Murcia fault. Along with other major faults such as the Carrascoy and the Palomares faults, and some secondary related minor fractures, the whole system may absorb part of the deformation related to the convergence between Iberia and North Africa (4-5 mm/yr). As a result, the system show a moderate seismic activity; however some large and damaging events have occurred in the area. Notably, the most recent significant earthquake was a 5.1 magnitude event in 2011, which occurred near the town of Lorca and was associated to the Alhama de Murcia fault. In addition, active tectonics and paleoseismological studies carried out in all the system have shown that faults have produce large earthquakes during the Holocene and late Quaternary. Even though, there is still a lack of knowledge about the deep structure of the faults. In order to address this shortcoming, we have acquired high-resolution seismic reflection transects, one across the Palomares Fault, three across the Alhama de Murcia fault, and one across the Carrascoy fault. The seismic data was acquired using a mini-Vib system, which provided sufficient energy to produce seismic sections reaching depths of over 2 km. The resulting high-resolution seismic reflection images are allowing to unveil the deep structure and geometry of the region, providing valuable insights into the upper Neogene deformation history. Additionally, these images have revealed fracture branches in the subsurface, contributing to a better understanding of the region's geological charact

[EN]: To produce seismic hazard assessments to the current state-of-the-art, it is essential to characterize the active faults in terms of geometry, interrelation and seismotectonic status. The Guadalentin Depression is the main basin within the Eastern Betic Shear Zone, which corresponds to a NE-SW tectonic corridor bounded by the Carrascoy, Alhama de Murcia and Palomares faults, from north to south. Although a number of active tectonics and paleoseismological studies have been carried out in these faults, almost nothing is known about their geometry at depth. To unveil the deep structure, geometry and upper Neogene deformation history of these faults we have carried out a high-resolution seismic reflection survey. The acquired seismic profiles will allow to improve our understanding of the deep geometry of the known active faults (up to 2 km depth), as well as to identify potential buried branches and will help to reduce the uncertainties in seismic hazard assessment., [ES]: Para producir evaluaciones del peligro sísmico actualizadas al estado del arte actual, es esencial caracterizar las fallas activas de una región en términos de geometría, interrelación y estado sismotectónico. La depresión del Guadalentín es la principal cuenca cuaternaria dentro de la Zona de Cizalla de las Béticas Orientales, la cual corresponde a un corredor tectónico con dirección NE-SW delimitado por las fallas de Carrascoy, Alhama de Murcia y Palomares, de norte a sur. Aunque varios estudios de tectónica activa y paleosismología se han centrado en estas fallas, su geometría en profundidad es bastante incierta. Para revelar la estructura profunda, la geometría y el historial de deformación desde el Neógeno superior de estas fallas, hemos llevado a cabo un estudio de sísmica de reflexión de alta resolución. Los perfiles sísmicos adquiridos permitirán mejorar nuestra comprensión de la geometría profunda de las fallas activas conocidas (hasta 2 km de profundidad), así como identificar posibles ramas ciegas, y ayudarán a reducir las incertidumbres en los cálculos de peligrosidad sísmica

The Algorithms for Lattice Fermions package provides a general code for the finite-temperature and projective auxiliary-field quantum Monte Carlo algorithm. The code is engineered to be able to simulate any model that can be written in terms of sums of single-body operators, of squares of single-body operators and single-body operators coupled to a bosonic field with given dynamics. The package includes five pre-defined model classes: SU(N) Kondo, SU(N) Hubbard, SU(N) t-V and SU(N) models with long range Coulomb repulsion on honeycomb, square and N-leg lattices, as well as $Z_2$ unconstrained lattice gauge theories coupled to fermionic and $Z_2$ matter. An implementation of the stochastic Maximum Entropy method is also provided. One can download the code from our Git instance at https://git.physik.uni-wuerzburg.de/ALF/ALF/-/tree/ALF-2.0 and sign in to file issues., Comment: 121 pages, 11 figures. v3: quick tutorial section added, typos corrected, etc. Submission to SciPost. arXiv admin note: text overlap with arXiv:1704.00131

Hydraulic fracturing is a proven technique for improving both hydrocarbon productivity and water and gas injection. The Colombian foothills exhibit a special configuration of factors that increase the difficulty both during the injection and production processes, as well as in the hydraulic fracturing process due to high tectonism, structural complexity, low permeability and high depth of the reservoirs of interest.The wells located in the Colombian foothills, operated in the past by BP & Equion and currently by Ecopetrol, have been fractured in the majority to obtain economically profitable production rates. During the history of fracturing, structural complexity, high depths, high fracture gradients and high reservoir pressures have led to the usage of high strength / high density proppants such as bauxite whose physical and chemical properties complied with the technical requirements of the wells. Although this material has good properties of resistance upon closure stresses, high concentrations were normally required which, in addition to its high density, implied the use of highly viscous transport fluids requiring higher concentrations of polymer in the fluid and therefore higher levels of damage induced to formation by both, fluids and solids generated due to the ´crushing´ effect of the proppant. In recent years, it has been documented that the Pauto and Floreña formations are very sensitive to external fluids due to their low permeabilities. Based on this, this project was planned for the application of a new mixture of fluids with low polymer concentration and new proppants with better conductivity and lower density, which were tested at the laboratory level prior to field applications. This fracturing campaign was the first of its kind using fluids with the lowest concentrations in the history of the fields and is considered a benchmark for Latin America, due to its excellent results financially and production wise., El fracturamiento hidráulico de pozos es una técnica comprobada de mejora tanto de la productividad de hidrocarburos como de la inyectividad de agua y gas. El piedemonte llanero colombiano presenta una especial configuración de factores que dificultan tanto el proceso de inyección como el de producción, así como el proceso de fracturamiento hidráulico debido al alto tectonismo, la complejidad estructural, la baja permeabilidad y la profundidad de los yacimientos de interés. Los pozos ubicados en el Piedemonte Colombiano y que fueron operados por BP, Equion y actualmente por Ecopetrol han sido fracturados en su gran mayoría para obtener tasas de producción económicamente rentables. Durante la historia de fracturamiento debido a la complejidad estructural, profundidad, los altos gradientes de fractura y las altas presiones de yacimiento; el propante utilizado fue del tipo sintético de mineral de bauxita cuyas propiedades físicas y químicas se ajustaban a los requerimientos técnicos de los pozos. Aunque este material presenta buenas propiedades de resistencia al esfuerzo de cierre, en general fueron requeridas altas concentraciones que, sumadas a la alta densidad del material, implicaron el uso de fluidos de acarreo altamente viscosos necesitando mayores concentraciones de polímero en el fluido y por ende mayores niveles de daño inducido a la formación tanto por fluidos como por sólidos generados debido al efecto de trituramiento ó ´crushing´. Durante los últimos años se ha detectado que las formaciones de Pauto y Floreña son muy sensibles a fluidos externos y debido a las bajas permeabilidades. En función de esto, el presente proyecto fue planeado para la aplicación de una nueva mezcla de fluidos de baja concentración polimérica y nuevos propantes de mejores propiedades de conductividad y densidad, que fueron probados a nivel de laboratorio previo a las aplicaciones en campo. Esta campaña de fracturamiento fue la primera en su tipo usando fluidos con las más bajas c

The Algorithms for Lattice Fermions package provides a general code for the finite-temperature and projective auxiliary-field quantum Monte Carlo algorithm. The code is engineered to be able to simulate any model that can be written in terms of sums of single-body operators, of squares of single-body operators and single-body operators coupled to a bosonic field with given dynamics. The package includes five pre-defined model classes: SU(N) Kondo, SU(N) Hubbard, SU(N) t-V and SU(N) models with long range Coulomb repulsion on honeycomb, square and N-leg lattices, as well as $Z_2$ unconstrained lattice gauge theories coupled to fermionic and $Z_2$ matter. An implementation of the stochastic Maximum Entropy method is also provided. One can download the code from our Git instance at https://git.physik.uni-wuerzburg.de/ALF/ALF/-/tree/ALF-2.4 and sign in to file issues., Comment: 126 pages, 12 figures. v7: update do ALF 2.4. Submission to SciPost. This article supersedes arXiv:1704.00131

Hydraulic fracturing is a proven technique for improving both hydrocarbon productivity and water and gas injection. The Colombian foothills exhibit a special configuration of factors that increase the difficulty both during the injection and production processes, as well as in the hydraulic fracturing process due to high tectonism, structural complexity, low permeability and high depth of the reservoirs of interest.The wells located in the Colombian foothills, operated in the past by BP & Equion and currently by Ecopetrol, have been fractured in the majority to obtain economically profitable production rates. During the history of fracturing, structural complexity, high depths, high fracture gradients and high reservoir pressures have led to the usage of high strength / high density proppants such as bauxite whose physical and chemical properties complied with the technical requirements of the wells. Although this material has good properties of resistance upon closure stresses, high concentrations were normally required which, in addition to its high density, implied the use of highly viscous transport fluids requiring higher concentrations of polymer in the fluid and therefore higher levels of damage induced to formation by both, fluids and solids generated due to the ´crushing´ effect of the proppant. In recent years, it has been documented that the Pauto and Floreña formations are very sensitive to external fluids due to their low permeabilities. Based on this, this project was planned for the application of a new mixture of fluids with low polymer concentration and new proppants with better conductivity and lower density, which were tested at the laboratory level prior to field applications. This fracturing campaign was the first of its kind using fluids with the lowest concentrations in the history of the fields and is considered a benchmark for Latin America, due to its excellent results financially and production wise., El fracturamiento hidráulico de pozos es una técnica comprobada de mejora tanto de la productividad de hidrocarburos como de la inyectividad de agua y gas. El piedemonte llanero colombiano presenta una especial configuración de factores que dificultan tanto el proceso de inyección como el de producción, así como el proceso de fracturamiento hidráulico debido al alto tectonismo, la complejidad estructural, la baja permeabilidad y la profundidad de los yacimientos de interés. Los pozos ubicados en el Piedemonte Colombiano y que fueron operados por BP, Equion y actualmente por Ecopetrol han sido fracturados en su gran mayoría para obtener tasas de producción económicamente rentables. Durante la historia de fracturamiento debido a la complejidad estructural, profundidad, los altos gradientes de fractura y las altas presiones de yacimiento; el propante utilizado fue del tipo sintético de mineral de bauxita cuyas propiedades físicas y químicas se ajustaban a los requerimientos técnicos de los pozos. Aunque este material presenta buenas propiedades de resistencia al esfuerzo de cierre, en general fueron requeridas altas concentraciones que, sumadas a la alta densidad del material, implicaron el uso de fluidos de acarreo altamente viscosos necesitando mayores concentraciones de polímero en el fluido y por ende mayores niveles de daño inducido a la formación tanto por fluidos como por sólidos generados debido al efecto de trituramiento ó ´crushing´. Durante los últimos años se ha detectado que las formaciones de Pauto y Floreña son muy sensibles a fluidos externos y debido a las bajas permeabilidades. En función de esto, el presente proyecto fue planeado para la aplicación de una nueva mezcla de fluidos de baja concentración polimérica y nuevos propantes de mejores propiedades de conductividad y densidad, que fueron probados a nivel de laboratorio previo a las aplicaciones en campo. Esta campaña de fracturamiento fue la primera en su tipo usando fluidos con las más bajas c

Neural networks are important tools for data-intensive analysis and are commonly applied to model non-linear relationships between dependent and independent variables. However, neural networks are usually seen as "black boxes" that offer minimal information about how the input variables are used to predict the response in a fitted model. This article describes the \pkg{NeuralSens} package that can be used to perform sensitivity analysis of neural networks using the partial derivatives method. Functions in the package can be used to obtain the sensitivities of the output with respect to the input variables, evaluate variable importance based on sensitivity measures and characterize relationships between input and output variables. Methods to calculate sensitivities are provided for objects from common neural network packages in \proglang{R}, including \pkg{neuralnet}, \pkg{nnet}, \pkg{RSNNS}, \pkg{h2o}, \pkg{neural}, \pkg{forecast} and \pkg{caret}. The article presents an overview of the techniques for obtaining information from neural network models, a theoretical foundation of how are calculated the partial derivatives of the output with respect to the inputs of a multi-layer perceptron model, a description of the package structure and functions, and applied examples to compare \pkg{NeuralSens} functions with analogous functions from other available \proglang{R} packages., Comment: 28 pages, 12 figures, submitted to Journal of Statistical Software (JSS) https://www.jstatsoft.org/index

Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine and Petroleum Geology 36 (2012): 70-82, doi:10.1016/j.marpetgeo.2012.05.008., The north flowing Falkland / Malvinas Current has generated sediment drifts at a depth of 1200-1600 m in the Patagonian middle continental slope out of early Holocene hemipelagics, late Pleistocene ice rafted clastics, and Neogene fluvial sediments. Possibly there may be two generations of drifts, Pleistocene on the outer middle slope and Holocene on the inner shelf. The ice rafted debris originated in Antarctica, at a distance of 2000 to 4000 km south of Patagonia. Scattered over the upper and middle slopes, at depths ranging from 300 to 1400 m, are cold-water coral reefs of less than a meter to about ten of meters in relief. It is inferred that most of cold-water coral structures flourish as a consequence of the Falkland /Malvinas Current that concentrates the food supply at the reef sites. Growth of cold-water coral reefs, documented by digital submarine photographs on the upper slope, at a depth of 300/400 m, may be promoted by upwelling of nutrient-rich waters and associated plankton blooms created by the intrusion of Falkland /Malvinas Current onto the outer shelf., Funding for this study was provided by IEO in collaboration with SGM.

The north flowing Falkland / Malvinas Current has generated sediment drifts at a depth of 1200-1600 m in the Patagonian middle continental slope out of early Holocene hemipelagics, late Pleistocene ice rafted clastics, and Neogene fluvial sediments. Possibly there may be two generations of drifts, Pleistocene on the outer middle slope and Holocene on the inner shelf. The ice rafted debris originated in Antarctica, at a distance of 2000 to 4000 km south of Patagonia. Scattered over the upper and middle slopes, at depths ranging from 300 to 1400 m, are cold-water coral reefs of less than a meter to about ten of meters in relief. It is inferred that most of cold-water coral structures flourish as a consequence of the Falkland /Malvinas Current that concentrates the food supply at the reef sites. Growth of cold-water coral reefs, documented by digital submarine photographs on the upper slope, at a depth of 300/400 m, may be promoted by upwelling of nutrient-rich waters and associated plankton blooms created by the intrusion of Falkland /Malvinas Current onto the outer shelf.

In March 2008 the Instituto Español de Oceanografía (IEO) through its Oceanographic Centre in Vigo (IEO-COV) initiated a historical series of research cruises aiming the assessment of the main commercial stocks on the High Seas (HS) of the SW Atlantic, including the study of two cephalopod species of important commercial interest, Argentine short-fin squid (Illex argentinus) and Patagonian squid (Loligo gahi). This working document presents a brief description of the methodology used in the cruises and preliminary results concerning CPUE by depth strata and geographical distribution of both mentioned species.

A checklist of Sphingidae in Galicia is provided based on the study of some of the main public and private collec-tions and our own fieldwork. This checklist includes the addition of 4 species previously unrecorded from Galicia, which makes a total of 17 especies recorded from this region., Se realiza una revisión de la familia Sphingidae en Galicia, basándonse en el estudio de algunas colecciones públicas y nuestros propios datos. Se citan 4 especies nuevas para el catálogo de esfíngidos gallegos, con lo que son 17 las presentes en Galicia.

In March 2008 the Instituto Español de Oceanografía (IEO) through its Oceanographic Centre in Vigo (IEO-COV) initiated a historical series of research cruises aiming the assessment of the main commercial stocks on the High Seas (HS) of the SW Atlantic, including the study of two cephalopod species of important commercial interest, Argentine short-fin squid (Illex argentinus) and Patagonian squid (Loligo gahi). This working document presents a brief description of the methodology used in the cruises and preliminary results concerning CPUE by depth strata and geographical distribution of both mentioned species.

In March 2008 the Instituto Español de Oceanografía (IEO) through its Oceanographic Centre in Vigo (IEO-COV) initiated a historical series of research cruises aiming the assessment of the main commercial stocks on the High Seas (HS) of the SW Atlantic, including the study of two cephalopod species of important commercial interest, Argentine short-fin squid (Illex argentinus) and Patagonian squid (Loligo gahi). This working document presents a brief description of the methodology used in the cruises and preliminary results concerning CPUE by depth strata and geographical distribution of both mentioned species.

In March 2008 the Instituto Español de Oceanografía (IEO) through its Oceanographic Centre in Vigo (IEO-COV) initiated a historical series of research cruises aiming the assessment of the main commercial stocks on the High Seas (HS) of the SW Atlantic, including the study of two cephalopod species of important commercial interest, Argentine short-fin squid (Illex argentinus) and Patagonian squid (Loligo gahi). This working document presents a brief description of the methodology used in the cruises and preliminary results concerning CPUE by depth strata and geographical distribution of both mentioned species.

In March 2008 the Instituto Español de Oceanografía (IEO) through its Oceanographic Centre in Vigo (IEO-COV) initiated a historical series of research cruises aiming the assessment of the main commercial stocks on the High Seas (HS) of the SW Atlantic, including the study of two cephalopod species of important commercial interest, Argentine short-fin squid (Illex argentinus) and Patagonian squid (Loligo gahi). This working document presents a brief description of the methodology used in the cruises and preliminary results concerning CPUE by depth strata and geographical distribution of both mentioned species.

Dentro del plan general de la campaña "Antártida 8611" se incluyó una prospección pesquera comercial por pescas exploratorias. Estas se llevaron a cabo en el B/F Nuevo Alcocero, en las plataformas de los archipiélagos del Arco de Scotia, con dos tipos de artes, semipelágico y pelágico, en función de las especies objetivos. Con el primero de estos aparejos se obtuvieron bajos rendimientos comerciales de especies demersales, por lo que se dedicó un mayor esfuerzo a la prospección de krill. Este informe analiza las capturas, rendimientos y composición en longitud de la captura obtenidos con los dos tipos de aparejos en cada una de las zonas prospectadas., Results of "Antártida 8611" cruise. Exploratory fisheries Within the general scope of the programme "Antártida 8611" an exploratory commercial fisheries survey was conducted. This was carried out on board R/V Nuevo Alcocero on the continental shelf of Scotia Are, with semipelagic and pelagic gears, depending on the target species. With the semipelagic gear very low commercial yields of demersal species were obtained. For this reason, the main effort was focussed on krill surveys. This report analyses the catches, yields and lenght composition of the catches obtained with the two types of gear in each of the areas surveyed.

En el presente trabajo se incluyen los resultados obtenidos durante la campaña <>, realizada en el sector Atlántico del Océano Austral en el período comprendido entre noviembre de 1986 y febrero de 1987. Esta primera prospección pesquera española en la zona fue realizada a bordo del Bj F <>, pesquero comercial especialmente equipado para la ocasión. El área objeto de estudio comprendió la plataforma de todos los archipiélagos del Arco de Escocia hasta la profundidad de 500 metros y el objetivo biológico pesquero fue el estudio de los recursos pesqueros antárticos. Se utilizó un arte semipelágico con una luz de malla de 68 mm en el copo. Los experimentos de selectividad se realizaron por el método del copo cubierto. Se han hecho estimaciones de biomasa por el método del área barrida (Saville, 1978) de siete especies pertenecientes a la familia Nototheniidae y cuatro a la familia Channichthyidae. Se observó una disminución de la biomasa global a medida que aumentó la latitud. Con respecto a la profundidad, el estrato más densamente poblado fue el comprendido entre 150 y 250 metros. Champsocephalus gunnari Lonnberg, 1905, fue la especie más abundante de la región si bien se localizaron las mayores concentraciones en Shag Rocks y Georgia del Sur., This report includes the results obtained during the scientific cruise from <>, carried out during the antarctic summer (November 1986-February 1987), in the Southern Ocean. The first spanish trawling survey in the area was carried out on board the <> a commercial fishing vessel especially equipped for the research cruise. The area of study was extended to the continental shelf of the archipelagos in the Scotia Sea up to 500 metres in depth and the objetive of the fisherie-biology was to study antarctic fisheries resources. A semipelagic gear was used with mesh size of 68 mm in the cod-end. For the selectivity experiments the covered cod-end technique was used. The stock size of seven Nototheniidae and tour Channichthyidae was estimated by <> (Saville, 1978). A decline was detected in the global biomass with latitude. Related to depth, that of 150-250 metres was the most heavily populated. Champsocephalus gunnari Lonnberg, 1905, was the most abundant species in the region, although it was mostly concentrated around Shag Rocks and South Georgia.