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22 pages, 9 figures

Trabajo presentado en el AGU (American Geophysical Union) Fall Meeting: Advancing Earth and Space Science, celebrado en Washington D.C. (Estados Unidos), del 10 al 14 de diciembre de 2018, The Lorca region, located in the Alto Guadalentín Basin, southern Spain, shows the highest subsidence rates recorded in Europe (about 10 cm/yr). It is produced by a long-term aquifer exploitation (González and Fernández, 2011; Bonì et al., 2014). This process has been studied in various works using interferometric synthetic aperture radar (InSAR) with images acquired from different satellites (ERS and ENVISAT radar data spanning the 1992 – 2007 period; ALOS PALSAR data for the period 2007–2010; and COSMO-SkyMed data for the period 2011–2012). González et al. (2012) established a relationship between the crustal unloading produced by the groundwater overexploitation and the stress change on the regional active tectonic faults in relation with the May 2008 Lorca earthquake. Those previous studies, based on InSAR and using either ascending or descending acquisitions, assumed that the surface displacement direction is entirely vertical. However, it is important to obtain the complete 3D motion field in order to perform a correct interpretation of the observations, as well as to carry out an advanced numerical model of the aquifer evolution, to be considered for sustainable management plans of groundwater resources and hazard assessments. To achieve this goal, GNSS surveys have been carried out from 2015 to 2018, showing the regional 3D displacement field associated to the exploitation of the aquifer (Prieto et al., 2016; Fernández et al. 2017). Also, simultaneous ascending and descending InSAR observations have been used, along with structural gravimetry (Camacho et al., 2015) and microgravity to study the subsidence area in a more complete geodetic way. We present the results obtained from all those techniques, their comparison, and the interpretation results using different inversion techniques (Tiampo et al., 2011; Camacho et al., 2011, 2015; Cannavò et al., 2015).

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 8 al 13 de abril de 2018, The extraction of raw materials is constrained by hazards linked to mining activities. Earthworks and pumping change soil mechanical properties and can cause landslides, subsidence or runoff drifting with potential serious economic, environmental and human-life consequences. The present research aims to reduce mining hazards by developing a “real time” system for monitoring ground instabilities. Our approach combines SAR Copernicus data (Sentinel-1) for surface deformation modeling and passive seismic data for subsurface imaging. Both data sources require low maintenance, can be automatized, record non-stop and fully cover the target zone; all suitable characteristics for an Early Warning System tool. This pilot study is being performed in the world-class Riotinto mine, SW Spain, with mining activity going back for more than 4000 years. A-DInSar techniques (CPT) have been used for processing Sentinel-1 images to establish the baseline surface deformation field. Our algorithm will automatically update the image catalogue and the surface deformation model. Environmental and anthropogenic “seismic noise” will be used for the subsurface imaging. The mining activities generate a broad variety of acoustical signal. Currently, the main seismic sources are being characterized. Autocorrelation and noise interferometry techniques will be use for underground dynamic imaging. Both datasets will be integrated into a new protocol for monitoring the mechanical integrity of the shallow subsurface, applicable to a wide range of environments, Research support, Ref: 248/G/GRO/COPE/16/9077 - Lot 2, CGL2016-81964-REDE, CGL2014-56548-P, ESP2013-47780-C2-1-R

Trabajo presentado en el ESA Consultation for a Regional Initiative over the Mediterranean - MED, celebrado en Frascati (Italia), del 11 al 12 de diciembre de 2018, The Geosciences Institute (IGEO: http://www.igeo.ucm-csic.es/en/igeo) is a joint center of the Spanish Research Council (CSIC) -the largest public institution dedicated to research in Spain- and the Complutense University (UCM) –the largest university in Spain- carrying out cutting-edge research related to Geology, Geodesy and Geophysics using a multidisciplinary approach. The aim of this poster is to show the main research lines and needs of the IGEO directly linked to the priorities addressed in the MED 2018 consultation meeting. We shall present those of our current activities which are more suited to contribute to the Atmospheric science and applications theme -particularly in the coupled feedback atmosphere/ocean/continental surfaces section- but also have strong impact in both Ocean Science and Land Science (e.g. geoinformation systems, Climate impacts on land environment,…) themes. Some examples of IGEO’s capabilities include satellite observation (e.g., InSAR, optical, gravity and magnetic), combined with in situ data, land instability and deformation as well as structures and infrastructures instability, associated to geological and antropogenic hazards. We have also developed and implemented techniques for interpretation and modeling and the different level observation and results can be implemented and distributed using the European Plate Observing System (EPOS) ESFRI infrastructure. From the climate view point, additional our main priorities should be focused on: 1) Detection of weather regimes and synoptic systems with automatic methods to better understand the atmospheric circulation variability and change, 2) Weather and climate extreme events from different perspectives, including climate change attribution to human activities, and 3) Effect of weather regimes on air pollutants such as ozone and particulate matter to establish links between atmospheric composition and circulation. IGEO is included into CSIC's Natural Resources Research Area, which gathers nearly 20 research institutes, including various singular facilities (e.g. Doñana Biological Station (EBD: http://www.ebd.csic.es) or Mediterranean Institute of Advanced Research (IMEDEA: http://imedea.uib-csic.es/centre.php), and specialized centers (e.g. Ebro Observatory (OE: http://www.obsebre.es/). We shall also provide a brief overview of the activities, projects and initiatives carried out at CSIC where ESA's EO may definitively contribute.

Trabajo presentado en Fringe, celebrado en Helsinki (Finlandia), del 5 al 9 de junio de 2017, We present and discuss first results in Spain achieved on the application of Sentinel-1 mission for the monitoring and survey of relatively small and isolated hydrological critical infrastructures like a dam and its surroundings. We describe the results obtained for the Siles dam, located in the province of Jaén (Spain), during its settlement and initial load process. ESA´s Sentinel-1A Interferometric Wide Swath (IW) SAR data are used and processed using the Coherent Pixel Technique (CPT) algorithm. A comparison of the A-DInSAR results with in-situ measurements will be also given. First results for this comparison shows a good agreement between A-DInSAR and levelling for the maximum value of subsidence. The results show that Sentinels program can be a very good choice for this type of studies due its short repeat cycle and spatial resolution as well as the open data Access policy which permits to obtain a high number of images without charge. The last facilitates to define a sustainable operational monitoring system.

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 23 al 28 de abril de 2017, EPOS, the European Plate Observing System, is a long-term plan to facilitate the integrated use of data, data products, software and services, available from distributed Research Infrastructures (RI), for solid Earth science in Europe. Indeed, EPOS integrates a large number of existing European RIs belonging to several fields of the Earth science, from seismology to geodesy, near fault and volcanic observatories as well as anthropogenic hazards. The EPOS vision is that the integration of the existing national and trans-national research infrastructures will increase access and use of the multidisciplinary data recorded by the solid Earth monitoring networks, acquired in laboratory experiments and/or produced by computational simulations. The establishment of EPOS will foster the interoperability of products and services in the Earth science field to a worldwide community of users. Accordingly, the EPOS aim is to integrate the diverse and advanced European Research Infrastructures for solid Earth science, and build on new e-science opportunities to monitor and understand the dynamic and complex solid-Earth System. One of the EPOS Thematic Core Services (TCS), referred to as Satellite Data, aims at developing, implementing and deploying advanced satellite data products and services, mainly based on Copernicus data (namely Sentinel acquisitions), for the Earth science community. This work intends to present the technological enhancements, fostered by EPOS, to deploy effective satellite services in a harmonized and integrated way. In particular, the Satellite Data TCS will deploy five services, EPOSAR, GDM, COMET, 3D-Def and MOD, which are mainly based on the exploitation of SAR data acquired by the Sentinel-1 constellation and designed to provide information on Earth surface displacements. In particular, the planned services will provide both advanced DInSAR products (deformation maps, velocity maps, deformation time series) and value-added measurements (source model, 3D displacement maps, seismic hazard maps). Moreover, the services will release both on-demand and systematic products. The latter will be generated and made available to the users on a continuous basis, by processing each Sentinel-1 data once acquired, over a defined number of areas of interest; while the former will allow users to select data, areas, and time period to carry out their own analyses via an on-line platform. The satellite components will be integrated within the EPOS infrastructure through a common and harmonized interface that will allow users to search, process and share remote sensing images and results. This gateway to the satellite services will be represented by the ESA- Geohazards Exploitation Platform (GEP), a new cloud-based platform for the satellite Earth Observations designed to support the scientific community in the understanding of high impact natural disasters. Satellite Data TCS will use GEP as the common interface toward the main EPOS portal to provide EPOS users not only with data products but also with relevant processing and visualisation software, thus allowing users to gather and process on a cloud-computing infrastructure large datasets without any need to download them locally

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 23 al 28 de abril de 2017, The European volcanological community contributes to implementation of European Plate Observing System (EPOS) by making operational an integrated platform to guarantee a seamless access to the data provided by the European Solid Earth communities. To achieve this objective, the Volcano Observations Work Package (WP11) will implement a Thematic Core Services (TCS) which is planned to give access to the data and services provided by the European Volcano Observatories (VO) and some Volcanological Research Institutions (VRI; as university departments, laboratories, etc.); both types are considered as national research infrastructures (RI) over which to build the TCS. Currently, the networks on European volcanoes consist of thousands of stations or sites where volcanological parameters are continuously or periodically measured. These sites are equipped with instruments for geophysical (seismic, geodetic, gravimetric, electromagnetic), geochemical (volcanic plumes, fumaroles, groundwater, rivers, soils), environmental observations (e.g. meteorological and air quality parameters), as well as various prototypal monitoring systems (e.g. Doppler radars, ground based SAR). In Europe also operate laboratories for sample analysis (rocks, gases, isotopes, etc.), and almost continuous analysis of space-borne data (SAR, thermal imagery, SO2 and ash), as well as high-performance computing centres. All these RIs provide high-quality information (observations) on the current status of European volcanoes and the geodynamic background of the surrounding areas. The implementation of the Volcano Observations TCS is addressing technical and management issues, both considering the current heterogeneous state of the art of the volcanological research infrastructures in Europe. Indeed, the frame of the VO and VRI is now too fragmented to be considered as a unique distributed infrastructure, thus the main effort planned in the frame of the EPOS-IP is focused to create services aimed at providing an improved and more efficient access to the volcanological facilities and observations on active volcanoes. The main gap to be overcame to facilitate the access to this valued information and to make this fragmented community into a unique infrastructure is concerning the heterogeneity in the technical solutions to provide the access. To tackle with this issue, WP11 launched an internal questionnaire to survey the current status of the services among the partners involved in the project. The technical heterogeneity reflects also in the management issues, and in particular in the data policies, governance structures and financial perspectives. Indeed, each research infrastructure currently adopts a own data policy (moreover, in some cases it is difficult to define a proper data policy), refers to different financial models and has different organization, also due to the different formal commitments of VO and/or VRI in own countries. Furthermore, to guarantee the sustainability of the TCS, a proper governance structure and financial model is under definition, with the twofold aim to guarantee the service provision and to represent the community. Thus the main challenging objective of the WP11 in the framework of EPOS-IP is to overcome the fragmentation and to strengthen the building of the European volcanological community which current worldwide high reputation is confirmed by the fact that three over four volcanic Supersites are located in Europe, managed by European institutions and were supported by EC through two EC-FP7 Projects (Futurevolc and MED-SUV).

Trabajo presentado en la European Geosciences Union General Assembly, celebrada en Viena (Austria), del 23 al 28 de abril de 2017, González and Fernández (2011) revealed that the Alto Guadalentín Basin, located in southern Spain, is affected by the highest subsidence rates measured in Europe (about 10 cm/yr) as a direct consequence of long-term aquifer exploitation. They used ERS and ENVISAT radar data spanning the 1992 – 2007 period. They identify a delayed transient nonlinear compaction of the Alto Guadalentín aquifer due to the 1990–1995 drought period. González et al. (2012) evaluated the relationship between crust unloading due to groundwater overexploitation and stress change on regional active tectonic faults in the same in relation with the May 2008 Lorca earthquake. Bonì et al. (2014) extended these previous studies using advanced DInSAR techniques and ALOS PALSAR (2007–2010) and COSMO-SkyMed (2011–2012) radar images for the time period 1992–2012. Additionally, the satellite measurements provide locally comparable results with measurements acquired by two permanent GNSS stations located in the study area. Furthermore, new geological and hydrogeological data were collected and analyzed in order to assess aquifer system compressibility and groundwater level changes in the past 50 years. The comparison of these data with advanced DInSAR displacement measurements allowed for a better spatial and temporal understanding of the governing mechanisms of subsidence due to overexploitation of the Alto Guadalentín aquifer system. But even though the aforementioned achievements have been reached, all regional studies of the area to date are based on satellite radar interferometry using just ascending or descending acquisitions, without any combination among them to obtain vertical and horizontal (E-W) components. Therefore, only the regional LOS displacement field is known and it is assumed to correspond to vertical displacement. However, it is important to obtain the 3D motion field in order to perform a correct interpretation of the observations, as well as to carry out an advanced numerical model of the aquifer evolution, to be consider for sustainable management plans of groundwater resources and hazard assessments. With this objective, a GNSS network has been defined and various surveys have been carried out in November 2015, July 2016 and beginning of 2017. The results, showing the regional 3D displacement field associated to the exploitation of the aquifer are described and compared with the InSAR ones. First results (Prieto et al., 2016) confirm previous observations (e.g. Bonì et al., 2015) and suggest that the ad-hoc establishment of small-medium GNSS networks, represent a valuable technique for the spatio-temporal monitoring of the 3D displacement field of areas subjected to extensive groundwater extraction.

Trabajo presentado en Fringe, celebrado en Helsinki (Finlandia), del 5 al 9 de junio de 2017, We present new results on the deformation field for La Palma Island in the Canary Archipelago using A-DInSAR analysis of C-Band SAR images from ENVISAT satellite for a six-year period between years 2004 and 2010. The recent volcanic activity registered in La Palma (with seven eruptions in ca. A.D. 1480, 1585, 1646, 1677, 1712, 1949 and 1971) and the absence of any geodetic monitoring system implemented in the Island at the 90’s converts A-DInSAR studies in a basic information source for the study of surface displacements. From late 90’s several geodetic studies using GNSS, gravimetry and InSAR techniques have been carried out in the island (see Fernández et al., 2015 for a summary). In this study we updated previous radar satellite results by processing both geometries (ascending and descending), increasing the temporal coverage up to 2010 and, using a recently developed A-DInSAR processing technique, including an error estimation for the LOS mean velocity and deformation time series (“Subsidence” software, developed by the “Universitat Politècnica de Catalunya, see e.g., Blanco-Sánchez et al., 2008, and Centolanza, 2015). Our A-DInSAR results are compared with previous InSAR ones and with GNSS results obtained from several campaigns. A discussion and geological interpretation including the inversion of the results to obtain the deformation sources is also presented. Radar images have been provided by ESA through Cat.-1 13933 project.

Trabajo presentado en el 18th International Symposium on Geodynamics and Earth Tides: Intelligent Earth system sensing, scientific enquiry and discovery, celebrado en Trieste (Italia), del 5 al 9 de junio de 2016, We present new results on the deformation field for La Palma Island in the Canary Archipelago using A-DInSAR analysis of C-Band SAR images from ENVISAT and ERS-2 satellites for a six-year period between years 2004 and 2010. The recent volcanic activity registered in La Palma (with seven eruptions in ca. A.D. 1480, 1585, 1646, 1677, 1712, 1949 and 1971) and the absence of any geodetic monitoring system implemented in the Island at the 90¿s converts A-DInSAR studies in an basic information source for the study of surface displacements. From late 90¿s several geodetic studies using GNSS, gravimetry and InSAR techniques has been carried out in the island (see Fernández et al., 2015 for a summary). In this study we updated previous radar satellite results by increasing the temporal coverage up to 2010 and and using a recently developed A-DInSAR processing technique which includes an error estimation for the LOS mean velocity and deformation time series (¿Subsidence¿ software, developed by the ¿Universitat Politècnica de Catalunya, see e.g., Blanco-Sánchez et al., 2008, and Centolanza, 2015). Our A-DInSAR results are compared with previous InSAR ones and with GNSS results obtained from campaigns. A discussion and geological interpretation of the results is also presented. Radar images have been provided by ESA through Cat.-1 13933 project.

Trabajo presentado en el 18th International Symposium on Geodynamics and Earth Tides: Intelligent Earth system sensing, scientific enquiry and discovery, celebrado en Trieste (Italia), del 5 al 9 de junio de 2016, Lowering of the groundwater table is a significant problem in Mediterranean coastal areas, leading to saltwater intrusion, drying of wetlands, and the disappearance of rivers (Coccossis and Hénocque, 2001). Aquifer overdraft has been a concern for the management of the water resources, due to the potential irreversible loss of aquifer storage caused by aquifer-system compaction, and associated land subsidence (Galloway and Hoffmann, 2007). From a mechanical point of view, groundwater extraction from a confined aquifer reduces groundwater pore pressure. Because the overburden remains unchanged, the effective stress on the grain matrix of the aquifer increases, and the volume of the confined aquifer decreases, resulting in compaction and triggering surface subsidence. Therefore, the control of land subsidence could serve as a proxy for the management of the pore pressure change and groundwater flows in underlying aquifers (Galloway and Hoffmann, 2007). Our main interest is the study of the ground deformation occurring in the Lorca area, where ground deformation data indicate large-scale deformation being of the highest rates of groundwater-related land subsidence recorded in Europe (>10cm/yr).(González and Fernández, 2011; Boni et al., 2015). Ground subsidence induced by overexploitation of aquifers is a common problem affecting urban areas and can be well characterized by radar interferometry (Tomas et al., 2005; Herrera et al., 2009 and 2010, Bru et al., 2010). This deformation study will be complemented by the development, improvement and implementation of the necessary tools that will allow modelling and interpretation of the observations, as well as to evaluate possible interactions with other phenomena, such as the potential to influence faulting on nearby faults.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena (Austria) del 17 al 22 de abril de 2016., We present new results on the deformation field for La Palma Island in the Canary Archipelago using A-DInSAR analysis of C-Band SAR images from ENVISAT and ERS-2 satellites for a six-year period between years 2004 and 2010. The recent volcanic activity registered in La Palma (at historical and subhistorical times, there have been seven eruptions, in ca. A.D. 1480, 1585, 1646, 1677, 1712, 1949 and 1971) and the absence of any geodetic monitoring system implemented in the Island at the 90¿s converts A-DInSAR studies in an basic information source for the study of surface displacements. From late 90¿s several geodetic studies using GNSS, gravimetry and InSAR techniques has been carried out in the island. We improve previous radar satellite results by increasing the temporal coverage and using more images, which generates a greater interferogram set, and using a recently developed A-DInSAR processing technique which includes an error estimation for the LOS mean velocity and deformation time series (¿Subsidence¿ software, developed by the ¿Universitat Politècnica de Catalunya). Our A-DInSAR results are compared with previous InSAR ones and with GNSS results obtained from campaigns. A discussion and geological interpretation of the results is also presented. Radar images have been provided by ESA through Cat.-1 13933 project.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., A spatially dense crustal velocity field, based on up to 15 years of GNSS observations at more than 380 sites and extensively covering the Iberian Peninsula and Northern Africa, allow us to provide new insights into two main tectonic processes currently occurring in this area. We detected a slow large-scale clockwise rotation of the Iberian Peninsula with respect to a local pole located closely to the northwestern sector of the Pyrenean mountain range (Palano et al., 2015). Although this crustal deformation pattern could suggest a rigid rotating lithosphere block, this model would predict significant shortening along the Western (off-shore Lisbon) and North Iberian margin which cannot totally ruled out but currently is not clearly observed. Conversely, we favour the interpretation that this pattern reflects the quasi-continuous straining of the ductile lithosphere in some sectors of South and Western Iberia in response to viscous coupling of the NW Nubia and Iberian plate boundary in the Gulf of Cádiz. Furthermore, the western Mediterranean basin appears fragmented into independent crustal tectonic blocks, which delimited by inherited lithospheric shear structures and trapped within the Nubia-Eurasia collision, are currently accommodating most of the plate convergence rate. Among these blocks, an (oceanic-like western) Algerian one is currently transferring a significant fraction of the Nubia-Eurasia convergence rate into the Eastern Betics (SE Iberia) and likely causing the eastward motion of the Baleares Promontory. Most of the observed crustal ground deformation can be attributed to processes driven by spatially variable lithospheric plate forces imposed along the Nubia-Eurasia convergence boundary. Nevertheless, the observed deformation field infers a very low convergence rates as observed also at the eastern side of the western Mediterranean, along the Calabro Peloritan Arc, by space geodesy (e.g. Palano, 2015).

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., In this work we present a 3D map of coseismic displacements due to the 2014 Mw 6.0 South Napa earthquake, California, obtained by integrating displacement information data from SAR Interferometry (InSAR), Multiple Aperture Interferometry (MAI), Pixel Offset Tracking (POT) and GPS data acquired by both permanent stations and campaigns sites. This seismic event produced significant surface deformation along the 3D components causing several damages to vineyards, roads and houses. The remote sensing results, i.e. InSAR, MAI and POT, were obtained from the pair of SAR images provided by the Sentinel-1 satellite, launched on April 3rd, 2014. They were acquired on August 7th and 31st along descending orbits with an incidence angle of about 23◦ . The GPS dataset includes measurements from 32 stations belonging to the Bay Area Regional Deformation Network (BARDN), 301 continuous stations available from the UNAVCO and the CDDIS archives, and 13 additional campaign sites from Barnhart et al, 2014 [1]. These data constrain the horizontal and vertical displacement components proving to be helpful for the adopted integration method. We exploit the Bayes theory to search for the 3D coseismic displacement components. In particular, for each point, we construct an energy function and solve the problem to find a global minimum. Experimental results are consistent with a strike-slip fault mechanism with an approximately NW-SE fault plane. Indeed, the 3D displacement map shows a strong North-South (NS) component, peaking at about 15 cm, a few kilometers far from the epicenter. The East-West (EW) displacement component reaches its maximum (∼10 cm) south of the city of Napa, whereas the vertical one (UP) is smaller, although a subsidence in the order of 8 cm on the east side of the fault can be observed. A source modelling was performed by inverting the estimated displacement components. The best fitting model is given by a ∼N330◦ E-oriented and ∼70◦ dipping fault with a prevailing right-lateral motion. Both NS and UP components are well constrained while the residuals for the EW component are higher. Further analysis will be mainly focused on model improvements.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., La Palma volcanic island is one of the youngest of the Canary archipelago, being a composite volcano formed by three overlapping volcanic centers. There are clear onshore and offshore evidences of past giant landslides that have occurred during its evolution. Currently, the active Cumbre Vieja volcano is in an early development state (Carracedo et al., 2001). The study of flank instability processes aim to assess, among other hazards, catastrophic collapse and potential tsunami generation. Early studies of the potential instability of Cumbre Vieja volcano western flank have focused on the use of sparse geodetic networks (Moss et al. 1999), surface geological mapping techniques (Day et al. 1999) and offshore bathymetry (Urgeles et al. 1999). Recently, a dense GNSS network and satellite radar interferometry results indicate ground motion consistent with deep-seated creeping processes (Prieto et al. 2009, Gonzalez et al. 2010). In this work, we present a geomechanical advanced numerical model that captures the ongoing deformation processes at Cumbre Vieja. We choose the Finite Elements Method (FEM) which is based in continuum mechanics and is the most used for geotechnical applications. FEM has the ability of using arbitrary geometry, heterogeneities, irregular boundaries and different constitutive models representative of the geotechnical units involved. Our main contribution is the introduction of an inverse approach to constrain the geomechanical parameters using satellite radar interferometry displacements. This is the first application of such approach on a large volcano flank study. We suggest that the use of surface displacements and inverse methods to rigorously constrain the geomechanical model parameter space is a powerful tool to understand volcano flank instability. A particular important result of the studied case is the estimation of displaced rock volume, which is a parameter of critical importance for simulations of Cumbre Vieja tsunamigenic hazard assessment.

Trabajo presentado en la EGU General Assembly 2016 (European Geosciences Union), celebrada en Viena del 17 al 22 de abril de 2016., A recently proposed algorithm (Camacho et al., 2011) claims to rapidly estimate magmatic sources from surface geodetic data without any a priori assumption about source geometry. The algorithm takes the advantages of fast calculation from the analytical models and adds the capability to model free-shape distributed sources. Assuming homogenous elastic conditions, the approach can determine general geometrical configurations of pressured and/or density source and/or sliding structures corresponding to prescribed values of anomalous density, pressure and slip. These source bodies are described as aggregation of elemental point sources for pressure, density and slip, and they fit the whole data (keeping some 3D regularity conditions). Although some examples and applications have been already presented to demonstrate the ability of the algorithm in reconstructing a magma pressure source (e.g. Camacho et al., 2011,Cannavò et al., 2015), a systematic analysis of sensitivity and reliability of the algorithm is still lacking. In this explorative work we present results from a large statistical test designed to evaluate the advantages and limitations of the methodology by assessing its sensitivity to the free and constrained parameters involved in inversions. In particular, besides the source parameters, we focused on the ground deformation network topology, and noise in measurements. The proposed analysis can be used for a better interpretation of the algorithm results in real-case applications.

El objetivo principal fue determinar cómo se percibe la Planificación Urbana de la nueva ciudad de Olmos – 2015, por la población de la ciudad de Olmos la cual tiene una población de 46,484. La investigación se realizó con la colaboración del Proyecto Especial Olmos Tinajones – PEOT, el Ministerio de Vivienda Construcción y Saneamiento – MVCS, y la Municipalidad Distrital de Olmos MDO. Es una investigación de tipo aplicativa, de diseño no experimental y de nivel descriptivo, en la cual no se realizó manipulación de variables. Para lograr su objetivo se aplicaron encuestas a pobladores de la zona urbana, rural y profesionales de la nueva ciudad de Olmos; se utilizó la técnica de encuesta en escala de Likert que aplico como instrumentos cuestionarios, para el procesamiento de datos se examinó de forma critica el instrumento aplicado a fin de comprobar la integridad de sus respuestas, se diseñó una base de datos utilizando el programa estadístico SPSS versión 21 en español, en el cual se registró los datos procedentes del instrumento. Mediante el programa SPSS V21 y Microsoft Excel 2013 se determinó la confiabilidad del instrumento, mediante el Alfa de Crombach de 0,84, para luego elaborar la descripción de la muestra y de las variables con sus respectivos gráficos, cuyo resultado fue que la población percibe una débil cultura de colaboración entre los diferentes agentes sociales en la planificación urbana de la Nueva Ciudad de Olmos; concluyendo que la percepción de la planificación de la Nueva Ciudad de Olmos es buena en un 20% de la población , regular un 60% y un 20% siente rechazo a la misma. Lima Norte Escuela de Posgrado Dirección de Políticas Públicas

Trabajo presentado en el AGU (American Geophysical Union) Fall Meeting: Advancing Earth and Space Science, celebrado en San Francisco (Estados Unidos), del 12 al 16 de diciembre de 2016, Subsidence is a natural hazard that affects wide areas in the world causing important economic costs annually. It is estimated that there are over 150 cities in the world with serious problems of subsidence due to excessive groundwater withdrawal like the Po Valley (Italy), Mexico DC, San Joaquin Valley (USA) and Bangkok (Thailand). Globally, groundwater depletion rates have risen in recent decades and significant lowering of groundwater tables has been reported. Aquifer overdraft has been a concern for the management of water resources, due to the potential irreversible loss of aquifer storage caused by aquifer system compaction and associated land subsidence. From a mechanical point of view, groundwater extraction from a confined aquifer reduces groundwater pore pressure. Because the overburden remains unchanged, the effective stress on the grain matrix of the aquifer increases, and the volume of the confined aquifer decreases, resulting in compaction and triggering surface subsidence. The control of land subsidence could serve as a proxy for the management of pore pressure change and groundwater flows in underlying aquifers (Galloway & Hoffmann, 2007). Our main interest is to study the ground surface displacement and Coulomb stress transfer produced by an extended source located in a homogeneus, elastic and isotropic half-space, based on Geerstma¿s model (1973). This study implies the improvement, development and implementation of the tools necessary for modelling and interpretation of the observations, as well as to evaluate possible interactions with other phenomena, such as the potential to influence on nearby faults.

En el presente artículo se presentan un análisis de series temporales de datos relativos a la evolución niveles piezométricos de la zona del Alto del Guadalentín (Murcia) y un análisis paralelo de series temporales de datos GNSS referentes a las altitudes de la zona. El objetivo de este análisis pretende establecer posibles correlaciones entre la subsidencia recogida por la red de estaciones GPS nacionales y el aumento de la profundidad piezométrica a la que se encuentran los acuíferos. Este objetivo se desarrollará mediante el análisis de los niveles piezométricos en comparación con las diferencias de altitud registradas en estaciones GNSS nacionales.

Trabajo presentado en el AGU (American Geophysical Union) Fall Meeting: Advancing Earth and Space Science, celebrado en San Francisco (Estados Unidos), del 12 al 16 de diciembre de 2016, Sentinel-1 was the first Earth Observation satellite of the Copernicus program launched in 2014. Thanks to its advanced C-band radar payload, it is capable of offering SAR images with a great coverage (300x300 Km) at a non-square resolution of 5x20 m. The mission is designed to have a great revisiting time, recently improved up to 6 days thanks to the twin sensor Sentinel-1b launched in April 2016. All these characteristics make of this sensor a very powerful data source for continuous monitoring over large areas worldwide and for different geological applications. However, it is still pending of demonstration what could be the contribution of this mission for the monitoring of small and isolated critical infrastructures, typically performed with high resolution and X-band data.This presentation aims to present and discuss first results in Spain achieved on the application of this mission for the monitoring and survey of relatively small and isolated hydrological critical infrastructures like a dam and surroundings. In this work we present the performance on the measurements of deformations over the Siles dam in Jaén, South of Spain, considering the resolution of the sensor, the revisiting time, the surrounding topography and most important the orientation of the dam.It is done through the PSI processing of this very large stack of data performed by using the Subsidence software, based in the Coherent Pixels Technique (CPT) algorithm, which allows us to derive very dense time series for correlation analysis of deformation trends during the filling process in the reservoir.