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Every year, earthquakes cause thousands of casualties and high economic losses. For example, in the time frame from 1998 to 2018, the total number of casualties due to earthquakes was larger than 846 thousand people, and the recorded economic losses were about USD 661 billion. At present, there are no earthquake precursors that can be used to trigger a warning. However, some studies have analyzed land surface temperature (LST) anomalies as a potential earthquake precursor. In this study, a large database of global LST data from the Geostationary Operational Environmental Satellite (GOES) and AQUA satellites during the whole year 2020 has been used to study the LST anomalies in the areas affected by earthquakes. A total of 1350 earthquakes with a magnitude larger than M4 were analyzed. Two methods widely used in the literature have been used to detect LST anomalies in the detrended LST time series: the interquartile (IQT) method and the standard deviation (STD). To the authors’ knowledge, it is the first time that the confusion matrix (CM), the receiver operating characteristic curve (ROC), and some other figures of merit (FoM) are used to assess and optimize the performance of the methods, and to select the optimum combination that could be used as a proxy for their occurrence. A positive anomaly was found a few days before the studied earthquakes, followed by the LST decrease after the event. Further studies over larger regions and more extended periods will be needed to consolidate these encouraging results. This work was sponsored by project “GENESIS: GNSS Environmental and Societal Missions—Subproject UPC”, Grant PID2021-126436OB-C21, sponsored by MCIN/AEI/10.13039/501100011033/ and EU ERDF “A way to do Europe”. Badr-Eddine Boudriki Semlali received support in the form of an FI grant: 2021 FI_B 00471 from Generalitat de Catalunya—FI AGAUR 2021.

Ionospheric disturbances induced by seismic activity have been studied in the last years by many authors, showing an impact both before and after the occurrence of earthquakes. In this study, the ionospheric scintillation produced by the 2021 La Palma volcano eruption is analyzed. The "Cumbre Vieja" volcano was active from September 19th to December 13th, 2021, and many magnitude 3–4 earthquakes were recorded, with some of them reaching magnitude 5. In this study the three methods: GNSS reference monitoring, GNSS Reflectometry (GNSS-R) from NASA CYGNSS, and GNSS Radio Occultation (GNSS-RO) from COSMIC and Spire constellations, are used, allowing us to compare and evaluate their performance in the same conditions. To compare the seismic activity with ionospheric scintillation, earthquakes’ generated energy, and percentile 95 % of the intensity scintillation parameter (S4), measurements have been computed every 6 h intervals for the whole duration of the volcanic eruption. GNSS-RO has shown the best correlation between earthquakes’ energy and S4, with values up to 0.09 when the perturbations occur around 18 h after the seismic activity. GNSS reference monitoring stations data also shows some correlation 18 h after and 7–8 days after. As expected, GNSS-R is the one that shows the smallest correlation, as the ionospheric signatures get masked by the signature of the surface where the reflection is taking place. Additionally, as expected as well, the three methods show a smaller correlation during the week before earthquakes. This work was supported in part by the grant PID2021-126436OB-C21 from the Programa Estatal para Impulsar la Investigación Científico-Técnica y su Transferencia, del Plan Estatal de Investigación Científica, Técnica y de Innovación 2021-2023 (Spain) and in part by the European Social Fund (ESF). GNSS-RO Spire data has been provided by the European Space Agency through the ESA TPM SPIRE project id 67176.

Recent studies have shown possible signatures or precursors of seismic activity in the ionosphere. Our group is focusing on ionospheric scintillation associated with seismic activity. By the time this study was conducted, the sudden volcanic eruption in the Spanish La Palma island, starting on September 19th, opened a possibility to study the impact of this exceptional, well time-defined seismic event on the iono-sphere and the radio-wave propagation through it. A complete study measuring scintillation on GNSS signals and its correlation to seismic activity is presented in this extended abstract. In particular, scintillation data from two ground stations in the Canary Islands, NASA CYGNSS GNSS-Reflectometry and Spire GNSS Radio-Occultation measurements have been used. A linear correlation analysis has been conducted between S4, and the earthquakes generated energy in 6 h intervals. Small, and slightly positive regression coefficients have been found with almost all methods. © 2022 IEEE. was supported by the Spanish Ministry of Science, Innovation and Universities and EFRD, ”Sensing with Pioneering Opportunistic Techniques” SPOT, grant RTI2018-099008- BC21/AEI/10.13039/501100011033, and by the Unidad de Excelencia Maria de Maeztu MDM-2016-0600.

It is known that the VLF/LF radiation existing prior to large earthquakes is recorded in several seismically active countries of the world. The networks of this radiation consist of stationary transmitters and receivers. However, there are cases of large earthquakes, when existing networks cannot detect relevant EM radiation. In the present paper we focus on the optimal option of a mobile VLF/LF electromagnetic radiation network arrangement to ensure a detection of the upcoming earthquake precursor. We discuss new possibilities of arrangement of the VLF/LF mobile network based on certain physical considerations, which is relatively simplified and completely different from the existing stationary networks. The suggested design, will significantly increase the number of detected/ predicted earthquakes with the relevant EM emissions receivers, strategically placed in the regions of the increased tectonic and seismic activity.

Recent works have assessed the capability of deep neural networks of estimating the epicentral source region of a seismic event from a single-station three-channel signal. In all the cases, the geographical partitioning is performed by automatic tessellation algorithms such as the Voronoi decomposition. This paper evaluates the hypothesis that the source region estimation accuracy is significantly increased if the geographical partitioning is performed considering the regional geological characteristics such as the tectonic plate boundaries. Also, it raises the transformation of the training data to increase the accuracy of the predictive model based on a Projected Coordinate Reference (PCR) System. A deep convolutional neural network (CNN) is applied over the data recorded by the broadband stations of the Venezuelan Foundation of Seismological Research (FUNVISIS) in the region of 9.5 to 11.5ºN and 67.0 to 69.0ºW between April 2018 and April 2019. In order to estimate the epicentral source region of a detected event, several geographical tessellations provided by seismologists from the area are employed. These tessellations, with different number of partitions, consider the fault systems of the study region (San Sebastián, La Victoria and Morón fault systems). The results are compared to the ones obtained with automatic partitioning performed by the k-means algorithm. This work is partially supported by the Spanish Ministry of Economy and Competitivity under contract TIN2015-65316-P, by the Spanish Ministry of Science and Innovation under contract PID2019-107255GB-C22, and by the SGR programmes (2014-SGR-1051 and 2017-SGR-962) of the Catalan Government and has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 777778 (MATHROCKS).

This article belongs to the Special Issue Ionosphere Monitoring with Remote Sensing., Ionospheric perturbations affect the propagation of electromagnetic waves. These perturbations, besides being a problem for space communications, satellite navigation, and Earth observation techniques, could also be used as another Earth observation tool. Several recent studies showed correlations with earthquakes with ionospheric anomalies, but almost all of them use ground stations to measure the Total Electron Content (TEC) variations, and, in particular, the ones occurring after an earthquake. Here, a preliminary study is presented on how the ionospheric scintillation measured with GNSS-R instruments over oceanic regions shows a small, but detectable correlation with the occurrence of earthquakes, which in some cases occurs before the earthquakes. This study uses GNSS-R data from NASA CYGNSS Mission to measure the ionospheric amplitude scintillation (S4 ) for 6 months from March 2019 to August 2019, applying a statistical analysis based on confusion matrixes, and the Receiver Operating Characteristic (ROC) curves to correlate S4 anomalous variations to earthquakes. A small positive correlation is found between the ionospheric scintillation and the earthquakes during the six previous days. However, the study has some weakness because (a) a small number (∼45) of large (M > 6) earthquakes over oceanic regions are studied, (b) the region studied is close to the geomagnetic equator, where ionospheric scintillations are usual, and (c) the overall correlation is small., This work was supported by the Spanish Ministry of Science, Innovation and Universities and EFRD, “Sensing with Pioneering Opportunistic Techniques” SPOT, grant RTI2018-099008-BC21/AEI/10.13039/501100011033, and by the Unidad de Excelencia Maria de Maeztu MDM-2016-0600 and, Grant RYC-2016-20918 financed by MCIN/AEI /10.13039/501100011033 and by ESF Investing in your future.

Annually, earthquakes cause human and material losses. For instance, between 1998 and 2018, 846 thousand deaths and about US$ 661 billion of economic losses were recorded due to earthquakes. Currently, there is no clear precursor to forecast earthquakes. However, numerous investigations have attempted to find precursor proxies based on Land Surface Temperature (LST) anomalies. In this study, a big database collected from GOES/ABI instrument during the full year 2020 has been used to calculate the LST anomalies in the earthquakes zones. A total of 1350 earthquakes of Mw = 4 were studied in 2020. Two methods commonly used in the literature, the interquartile method, and the standard deviation of the time series, have been applied to detect LST anomalies. The confusion matrix, some figures of merit, and the receiver operating characteristic curve have been used to evaluate and enhance the performance of the methods and choose the optimum decision threshold. A positive anomaly is usually found before the earthquakes, followed by an LST decrease after the event. This work was supported by project SPOT: Sensing with Pioneering Opportunistic Techniques grant RTI2018- 099008-B-C21/AEI/10.13039/501100011033. Badr-Eddine Boudriki Semlali received support in an FI grant:2021 FI_B 00471 from FI AGAUR 2021.

Natural disasters are a significant threat to human development. In this paper, we analyze the effects of being exposed to a strong earthquake during school age on schooling outcomes. We merge geolocated data about the intensity of the shock at the district level with individual information from the Indonesia Family Life Survey. The identification strategy exploits variation in exposure to the natural shock by birth cohort and district of residence, considering as the treated group individuals who were residing in affected districts while they were in school age. Earthquake exposure reduces years of schooling by somewhat less than one year and negatively affects the probability of completing compulsory education but does not alter the chances of enrolling into post-compulsory education. Falsification analysis and several robustness checks corroborate the causal interpretation of our findings. The analysis of the potential mechanisms indicates that induced migration and casualties occurring at the family level as a consequence of the earthquake do not seem to play a relevant role. However, damages in educational infrastructures do represent a relevant channel through which natural disasters harm human capital formation. Part of the overall impact of the earthquake represents a delay in schooling progression, but a substantial share of its effect consists in a permanent loss of human capital among affected individuals.

Several factors may induce perturbations on the ionospheric plasma, changing its average electron density and creating small-scale irregularities, changing its shape and altitude. Solar irradiance and space weather are some of the main factors affecting the ionosphere. They produce a seasonal and daily dependence, modulated by the solar cycle, with more ionospheric activity during periods of higher solar activity. Recent studies shows that another source of perturbations for the ionosphere may be related to internal Earth parameters as seismic activity, in particular, earthquakes. In the period before an earthquake, rocks in the lithosphere are subjected to pressures and movements that may create variations of electromagnetic fields and low frequency waves interacting with the ionosphere. In this work, the ionospheric scintillation intensity index or S4 is estimated from GNSS-R data collected by NASA CYGNSS, and it is correlated with earthquakes events in 2020. Furthermore, it is compared with plasma fluctuation indices measured by ESA Swarm satellites. Two earthquakes in 2020 with magnitudes larger than 7 in the central America region are shown in this work. This work was supported by the Spanish Ministry of Science, Innovation and Universities and EFRD, ”Sensing with Pioneering Opportunistic Techniques” SPOT, grant RTI2018- 099008-BC21/AEI/10.13039/501100011033, and by the Unidad de Excelencia Maria de Maeztu MDM-2016-0600.

Comptes rendus geoscience 353(S1), 381-412 (2021). doi:10.5802/crgeos.98 special issue: "Seismicity in France = Sismicit�� en France / guest editors/r��dacteurs en chef invit��s: Carole Petit, St��phane Mazzotti, Fr��d��ric Masson", Published by Institut de Frances, Acad��mie des sciences, Paris

Including faults as seismogenic sources in probabilistic seismic hazard assessments (PSHA) has turned into a common practice as knowledge of active faults is improving. Moreover, the occurrence of earthquakes in multi-fault ruptures has evidenced the need to understand faults as interacting systems rather than independent sources. We present a PSHA for the Southeastern Spain obtained by including the faults of a moderate seismicity region, the Eastern Betics Shear Zone (EBSZ) in SE Spain, as the main seismogenic sources in two separate source models, one considering background seismicity. In contrast with previous studies in Spain, earthquake occurrence of the EBSZ system is modeled considering different hypotheses of multi-fault ruptures at the whole fault system scale and weighted in a logic tree. We compare the hazard levels with those from an area source PSHA and a previous fault-based approach. The results show a clear control of the EBSZ faults in the seismic hazard for all return periods, increasing drastically the hazard levels in the regions close to the fault traces and influencing up to 20 km farther with respect to the area source PSHA. The seismic hazard is dependent on the fault slip rates as peak ground accelerations and territorial extension of the fault influence appear higher around the Alhama de Murcia and Carboneras faults, while lower slip rate faults (Palomares Fault) show minor contribution to the hazard. For the return period of 475 years and near-fault locations, our models are more consistent with the ground motion values reached in the 2011 Mw 5.2 Lorca event than the building code or national seismic hazard map, which suggest that our fault system-based model performs more accurate estimations for this return period. Fault data, mainly slip rates, and its uncertainties have a clear impact on the seismic hazard and, for some faults, the lack of detailed paleoseismic studies can compromise the reliability of the hazard estimations. This, together with epistemic uncertainties concerning the background seismicity, are key discussion points in the present study, having an impact on further research and aiming to serve as a case example for other low-to-moderate seismicity regions worldwide.

Publicat en accés obert després de sis mesos d'embargament amb el permís de l'editor / Published in open access after six months of embargo with the permission of the publisher. Reliable earthquake detection algorithms are necessary to properly analyze and catalog the continuously growing seismic records. We report the results of applying a deep convolutional neural network, called UPC‐UCV (Universitat Politecnica de Catalunya ‐ Universidad Central de Venezuela), over single‐station three‐channel signal windows for P‐wave earthquake detection and source region estimation in north‐central Venezuela. The analysis is performed on a new dataset of handpicked arrivals of P waves from local events, named CARABOBO, built and made public for reproducibility and benchmarking purposes. The CARABOBO dataset consists of three‐channel continuous data recorded by the broadband stations of the Venezuelan Foundation for Seismological Research in the region of 9.5°–11.5°N and 67.0°–69.0°W during the time period from April 2018 to April 2019. During this period, 949 earthquakes were recorded in that area, corresponding to earthquakes with magnitudes in the range from Mw 1.1 to 5.2. To estimate the epicentral source region of a detected event, the proposed network employs geographical distribution of the CARABOBO dataset into K clusters as a basis. This geographical partitioning is automatically performed by the k‐means algorithm, and the optimality of the K‐values for our dataset has been assessed using the elbow (⁠K=5⁠) and silhouette (⁠K=3⁠) methods. For target seismicity, the proposed network achieves 95.27% detection accuracy and 93.36% source region estimation accuracy, when using K=5 geographic clusters. The location accuracy slightly increases to 95.68% in the case of K=3 geographic partitions. The detection capability of this network has also been tested on the OKLAHOMA dataset, which compiles more than 2000 local earthquakes that occurred in this U.S. state. Without any modification, the proposed network yields excellent detection results when trained and evaluated on that dataset (98.21% accuracy; ConvNetQuake, fine‐tuned for this dataset, achieves a 97.32% accuracy), corresponding to a totally different geographical region. This work is partially supported by the Spanish Ministry of Economy and Competitivity under contract TIN2015-65316-P, by the Spanish Ministry of Science and Innovation under contract PID2019-107255GB-C22, and by the SGR programmes (2017-SGR-1414 and 2017-SGR-962) of the Catalan Government. We also thank the Generalitat de Catalunya for providing additional funds under the RIS3CAT DRAC project (001-P-001723). The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under the ChEESE project, grant agreement No. 823844. Additionally, this project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 777778 MATHROCKS.

The intra‐arc Liquiñe‐Ofqui Fault System (LOFS) is an active transpressive fault zone located in the Patagonian Andes of Chile. In 2007, a seismic sequence occurred in the Aysén Fjord region of Chilean Patagonia along the LOFS, with a Mw 6.2 main earthquake that triggered dozens of landslides, some of which induced tsunami waves that caused severe damage and casualties. Through the analysis of high‐resolution seismic reflection and bathymetric data, we identify six submarine faults cutting the late‐Quaternary postglacial sedimentary infill of the fjord. The most conspicuous are the dextral‐normal NE‐SW‐striking Quitralco fault (QF) and the N‐S striking strike‐slip Río Cuervo (RCF) and Punta Cola faults (PCF). Our paleoseismological analysis reveals at least seven paleo‐landslide events buried in the fjord sediments, that were triggered by local paleoearthquakes, which occurred since local ice‐sheet retreat, i.e. ca. 12 kyrs. By combining tectonic observations with local seismicity data, we propose a seismotectonic model for the evolution of the 2007 seismic sequence where three structures were progressively activated from the depth towards the upper continental crust, causing surface rupture along the PCF and with earthquakes (i.e. partial ruptures along other faults). Because the other faults did not rupture to the seafloor they remain important sources of seismic hazard. Thus, the last seismic sequence was a consequence of a stress transfer from the lower‐ductile towards the upper‐brittle continental crust, close to the triple junction of the Nazca, South American and Antarctica Plates. Our results emphasize on the potential synergies between multiple geological and geophysical methods to assess complex events. Plain Language Summary When crustal faults rupture, the energy released are the earthquakes we feel at the surface of the Earth. Recent studies along strike‐slip faults, demonstrate that these phenomena are often not only related to a single fault, but instead take place along several faults like was seen in the 2016 Kaikoura earthquake in New Zealand. Using novel high‐resolution seismic reflection imagery and bathymetric data together with the reanalysis of local seismicity, we show (i) multiple active faults in the Aysén Fjord area along the Liquiñe‐Ofqui fault system in the Patagonian Andes, (ii) several of these faults were activated during the last 2007 seismic sequence and one of them (the Punta Cola fault), ruptured to the surface causing a Mw 6.2 earthquake that generated massive landslides and local tsunami, (iii) mapping of similar landslides in the fjord sediments demonstrates similar events occured at least seven times since the last ice‐sheet retreat in the area, i.e. in the last 12,000 years. This demonstrates the necessity for including the possibility of complex ruptures involving multiple faults regarding seismic hazard assessment along crustal faults, especially for faults near populated areas.

Globally, instrumentally based assessments of tsunamigenic potential of subduction zones have underestimated the magnitude and frequency of great events because of their short time record. Historical and sediment records of large earthquakes and tsunamis have expanded the temporal data and estimated size of these events. Instrumental records suggests that the Mexican Subduction earthquakes produce relatively small tsunamis, however historical records and now geologic evidence suggest that great earthquakes and tsunamis have whipped the Pacific coast of Mexico in the past. The sediment marks of centuries old-tsunamis validate historical records and indicate that large tsunamigenic earthquakes have shaken the Guerrero-Oaxaca region in southern Mexico and had an impact on a bigger stretch of the coast than previously suspected. We present the first geologic evidence of great tsunamis near the trench of a subduction zone previously underestimated as potential source for great earthquakes and tsunamis. Two sandy tsunami deposits extend over 1.5 km inland of the coast. The youngest tsunami deposit is associated with the 1787 great earthquake, M 8.6, producing a giant tsunami that poured over the coast flooding 500 km alongshore the Mexican Pacific coast and up to 6 km inland. The oldest event from a less historically documented event occurred in 1537. The 1787 earthquake, and tsunami and a probable predecessor in 1537, suggest a plausible recurrence interval of 250 years. We prove that the common believe that great tsunamis do not occur on the Mexican Pacific coast cannot be sustained.

Background The Ecuadorian earthquake in April 16th was the second strongest and deadliest in 2016 worldwide, with approximately one million people affected. In this paper, we analyzed the psychological impact and the relationship between mental health events and various earthquake-related stressors related to the earthquake, 9 months after the event. Methods We conducted an analytical cross-sectional study, applying an anonymous survey to 316 adolescents (13–19 years old) from Muisne, Ecuador. Suicidal tendency, depression, anxiety and post-traumatic stress (PTSD) were evaluated via the Child PTSD Symptom Scale (CPSS), Spence Children’s Anxiety Scale, Okasha Suicidality Scale, and the Center for Epidemiologic Studies Depression Scale (CES-D) and the adapted seven-questions earthquake-related stressors survey. Results We found a high prevalence of suicidal ideations and behavior, posttraumatic stress, depression and anxiety compared to international studies. Even though adolescents currently living in shelters had higher levels of anxiety, their suicidal tendency was significantly lower than those living in their own or their relatives’ home. Finally, the earthquake-related stressors were not associated with suicidality and mental health events, with the exception of economic damage suffered by the family. Conclusions High levels of depression, post-traumatic stress and anxiety among high-school students were found, especially among those who have suffered serious economic damage. The economic impact in their families and high unemployment rates among their parents seems to be related to lack of hope and favorable perspectives for their future, situation that might lead to lead to emotional disturbances and psychological disorders. Although prolonged homelessness experience in shelters may be a stressful occurrence, might also be related with spiritual growth among adolescents, and may work as a protective factor against suicidal ideations and attempts.

International audience; Earthquake surface fault ruptures can show very complex geometries and involve different faults simultaneously. Consequently, modern fault-based probabilistic seismic hazard assessments (PSHA) need to account for such complexities in order to achieve more realistic modellings that treat fault systems as a whole and consider the occurrence of earthquake ruptures as aleatory uncertainties. We use SHERIFS, a recent approach of modelling annual rates of complex multi-fault ruptures, to obtain system-level magnitude-frequency distributions (MFDs) for the Eastern Betics Shear Zone (EBSZ, Spain) considering four fault rupture hypotheses. We then analyze the consistency of each scenario based on data from the earthquake catalogue and paleoseismic studies. The definition of the different rupture hypotheses was discussed within the frame of Fault2SHA ESC working group and critical fault input data is extracted from previous published studies. The four rupture hypotheses are defined as incremental scenarios based on fault geometry and kinematics, with lengths varying from minimal fault sections to a rupture of nearly the whole system.The results suggest that multi-fault ruptures involving lengths up to single to several whole faults are consistent with the annual rates from both the instrumental catalogue and paleoseismic record. The method does not allow to completely discard any hypothesis, but it allows to weight the different models in a logic tree for seismic hazard assessment. The approach is revealed as a practical tool for obtaining fault-system MFDs and as a useful tool for highlighting limitations and uncertainties in geological and paleoseismic data to be assessed. This study aims to constitute a step forward in the consideration of complex multi-fault ruptures for future seismic hazard assessments in the region.

Seismic data can provide information to deduce the occurrence of mass movement events, their release time, event location and dynamics characterization [1]. Nevertheless, the effect of local site amplifications, the level of seismic noise and the frequency content of the signals are important constraints to correctly identify and describe these types of events. In this article we provide data on: site effects, power spectral densities, polarization particle motion and spectrograms generated by a rockslide (∼450 m3) (hereinafter NR) recorded in two permanent seismic stations (EPOB and POBL) located ∼10 km from the source. Original data are available through the International Federation of Digital Seismograph Networks (FDSN, http://www.fdsn.org) for POBL and on request from Instituto Geográfico Nacional (IGN, http://www.ign.es) for EPOB. POBL and EPOB site effects analysis by means of Horizontal-to-Vertical spectral ratio (H/V) technique shows important signatures in POBL signal between 1 and 10 Hz, indicating strong amplification effects at these frequencies, not present in EPOB. For frequencies >1 Hz, Power Spectral Densities (PSD) are higher in POBL than in EPOB, indicating that POBL is noisier than EPOB. Based on the H/V and PSD analyzes, the EPOB station data was deemed preferable over the POBL, to conduct the research presented in the related article [1]. Particle polarization motion data enabled the identification of the arrivals of P, S, and superficial waves, confirming that Pg waves were correctly identified, providing necessary information for the event location in the research article [1]. Moreover, EPOB and POBL spectrograms together with the Fourier transform are included to analyze their content in the frequency domain showing that the expected high frequency phenomenon of the rockslide recorded at 10 km is attenuated and only the low frequency content between 1 and 15 Hz is recorded. Keywords: Seismic data, Translational rock slide, Seismic quality control, Waves identification, Site effects

Deadly earthquakes are events that are unpredictable, relatively rare and have a huge impact upon the lives of those who suffer their consequences. Furthermore, each earthquake has specific characteristics (location, magnitude, directivity) which, combined to local amplification and de-amplification effects, makes their outcome very singular. Empirical relations are the main methodology used to make early assessment of an earthquake's impact. Nevertheless, the lack of sufficient data registers for large events makes such approaches very imprecise. Physics-based simulators, on the other hand, are powerful tools that provide highly accurate shaking information. However, physical simulations require considerable computational resources, a detailed geological model, and accurate earthquake source information. A better early assessment of the impact of earthquakes implies both technical and scientific challenges. We propose a novel HPC-based urgent seismic simulation workflow, hereafter referred to as Urgent Computing Integrated Services for EarthQuakes (UCIS4EQ), which can deliver, potentially, much more accurate short-time reports of the consequences of moderate to large earthquakes. UCIS4EQ is composed of four subsystems that are deployed as services and connected by means of a workflow manager. This paper describes those components and their functionality. The main objective of UCIS4EQ is to produce ground-shaking maps and other potentially useful information to civil protection agencies. The first demonstrator will be deployed in the framework of the Center of Excellence for Exascale in Solid Earth (ChEESE, https://cheese.coe.eu/, last access: 12 Feb. 2020). The ChEESE project has received funding from the European Union’sHorizon 2020 research and innovation programme under the grantagreement Number 823844. Further funding includes the SpanishMinistry project GAP TIN2016-80957-P, the EU project MATH-ROCKS Number 777778. The Graves-Pitarka Generator is availablethrough the SCEC Broadband Platform version 19.4. We acknowl-edge the assistance by Favio Silva and Phillip Maechling on itscompilation and execution.

El presente trabajo consiste en el desarrollo de una visualización de datos de los terremotos más significativos producidos en el planeta entre los años 2000 y 2020 utilizando Processing. El objetivo es comprobar las ventajas y desventajas de trabajar con Processing a la par que introducir a las personas interesadas en el ámbito de las visualizaciones de datos, explicando su importancia a lo largo de la historia y la actualidad y finalmente siguiendo todo el proceso de conceptualización, testeo y desarrollo de una. El desarrollo del trabajo está seccionado en muchos apartados, prácticamente a modo de tutorial, para que cada persona pueda centrarse en la fase del proyecto que le sea de mayor interés y utilidad, además de que así se permite mostrar de mejor manera las funcionalidades de Processing para los que no lo conocen y así puedan empezar a aprender a utilizarlo no sólo para visualizaciones de datos sino también para aplicar los conocimientos aprendidos en otros proyectos multimedia. Durante el proceso se muestran las diferentes decisiones tomadas en todas las fases del proyecto además de los diversos retos y problemas que se han presentado durante el desarrollo, incluyendo también las diferentes soluciones y alternativas para poder desarrollar la aplicación. En conclusión, se ha podido comprobar que Processing proporciona resultados óptimos en cuanto al desarrollo de aplicaciones multimedia de esta envergadura. Como resultado se ha conseguido una visualización de datos funcional y de alta fidelidad visual en comparación a los prototipos propuestos desde un inicio, cumpliendo de manera satisfactoria los objetivos propuestos

El presente trabajo final de máster se realiza con objeto de establecer una guía técnica en la Asociación Nuclear Ascó - Vandellós II, AIE para llevar a cabo la calificación sísmica de equipos y componentes relacionados con la seguridad, de categoría sísmica 1, en cumplimiento con las bases de licencia de las centrales nucleares (CCNN) de Ascó y Vandellós II. La calificación sísmica se desarrolla en base a requisitos normativos de distinto nivel, de ámbito nacional e internacional, a aplicar en instalaciones nucleares, donde destaca la Instrucción de Seguridad IS-27 Rev.1 [5] sobre criterios generales de diseño (trasladada del apéndice A del 10CFR50 [2]), la Instrucción de Seguridad IS-26 Rev.0 [23] sobre requisitos básicos de seguridad nuclear, el apéndice B del 10CFR50 [3] sobre criterios de garantía de calidad y la guía reguladora RG-1.100 Rev.1/2 [7] [8] sobre calificación sísmica de equipos. Se define el marco regulatorio de aplicación para ambas CCNN y acorde a la RG-1.29 Rev.3/4 [6] sobre clasificación de diseño sísmico, se procede con la clasificación de equipos y componentes que deben ser diseñados como categoría sísmica 1 para soportar los efectos del terremoto base de diseño (SSE). La calificación sísmica de equipos y componentes exige que todos aquellos que estén relacionados con la seguridad, diseñados como categoría sísmica 1, deben permanecer funcionales ante el máximo movimiento vibratorio del suelo provocado por el SSE, con objeto de: asegurar la integridad de la barrera de presión del refrigerante del reactor, ser capaces de parar el reactor manteniéndolo en condición de parada segura e impedir o mitigar las consecuencias de accidentes que pudieran causar exposiciones a dosis de radiación en el exterior de la central, superiores a las indicadas en el 10CFR100 “Reactor Site Criteria” [1]. La calificación sísmica se lleva a cabo mediante análisis, ensayos, o combinación de ambos según se establece en la norma principal de calificación sísmica IEEE 344 [9] avalada por la RG-1.100 Rev.1/2 [7] [8]. El objetivo es evidenciar que un equipo o componente puede realizar su función de seguridad bajo condiciones de un evento base de diseño (DBE). Por último, se integra en la calificación sísmica el concepto de margen sísmico establecido por NUREG-1407 “Procedural and Submittal Guidance for the Individual Plant Examination of External Events (IPEEE) for Severe Accident Vulnerabilities” [10] y desarrollado por EPRI en documento NP-6041-SLR1 “A Methodology for Assessment of Nuclear Power Plant Seismic Margin” [11]. El objetivo es el de garantizar el funcionamiento o integridad de equipos y componentes ante solicitaciones sísmicas que van más allá a las consideradas en el diseño original de la planta.

An earthquake is the vibration pattern of the Earth’s crust induced by the sliding of geological faults. They are usually recorded for later studies. However, strong earthquakes are rare, small-magnitude events may pass unnoticed and monitoring networks are limited in number and efficiency. Thus, earthquake catalog are incomplete and scarce, and researchers have developed simulators of such catalogs. In this work, we start from synthetic catalogs generated with the TREMOL-3D software. TREMOL-3D is a stochastic-based method to produce earthquake catalogs with different statistical patterns, depending on certain input parameters that mimics physical parameters. When an appropriate set of parameters are used, TREMOL-3D could generate synthetic catalogs with similar statistical properties observed in real catalogs. However, because of the size of the parameter space, a manual searching becomes unbearable. Therefore, aiming at increasing the efficiency of the parameter search, we here implement a Machine Learning approach based on Random Forest classification, for an automatic parameter screening. It has been implemented using the machine learning Python’s library SciKit Learn. This work is partially supported by the Spanish Ministry of Economy and Competitivity under contract TIN2015-65316-P and by the Catalan Government through the programmes 2017-SGR-1414, 2017-SGR-962 and the RIS3CAT DRAC project 001-P-001723. Moreover, this project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 777778 (MATHROCKS). The research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under the ChEESE project, grant agreement No. 823844.

Grain‐size analysis and end‐member modelling of a long sediment core from Aysén Fjord (southern Chile) allows to identify over 25 seismo‐turbidites in the last 9000 years. Considering the shaking intensities required to trigger these turbidites (V½‐VI½), the majority can be related to megathrust earthquakes. Multiple studies in south‐central Chile have aimed at finding traces of giant, tsunamigenic megathrust earthquakes leading to the current 5500‐year‐long paleoseismological record of the Valdivia Segment. However, none of these cover the southern third of the segment. Aysén Fjord allows to fill this data gap and presents the first, crucial paleoseismic data to demonstrate that the 1960 event was not unique for the Valdivia Segment, yielding a recurrence rate of 321 ± 116 years in the last two millennia. Moreover, the oldest identified events in Aysén Fjord date back to 9000 cal years BP, and thus also extend the regional paleoseismological record in time. We infer a large temporal variability in rupture modes, with successions of full‐segment ruptures alternating with partial and cascading ruptures. The latter seem to significantly postpone the occurrence of another full rupture when consecutively occurring in different parts of the segment. Additionally, one outstanding period of seismic quiescence – during which no megathrust earthquake evidence has been found at any paleoseismic site – occurred after a full rupture in AD ~745 that presents an unusual uplift/subsidence pattern. Such variability makes it highly speculative to anticipate the rupture mode of the next megathrust earthquake along the Valdivia Segment. Key Points Oldest evidence for megathrust earthquakes in southern Chile Confirmation of variable rupture model and first evidence for 1960‐like full‐segment ruptures along the Valdivia Segment Different rupture types influence full‐segment rupture recurrence rates

[ES] La tierra es un material historicamente utilizado en el mundo de la arquitectura. Actualmente en el S.XXI seguimos dependiendo de él, dado que este es un recurso abundante, económico y sostenible, que aporta buenas propiedades para su uso como material de construccion. Es por ello que lo vemos empleado sobretodo, en contextos de subdesarrollo. El presente proyecto da un guiño a la arquitectura de cooperación en países en vías de desarrollo, como es El Salvador, trabajando desde un principio en la reconstrucción del caserío de Potrerillos, en Alegría Usulután. Se prioriza una construcción principalmente sostenible, explotando el recurso natural de la tierra, e introduciendo así mismo a la arquitectura en el propio terreno, trabajando así con el término de arquitectura excavada. Mediante esta construcción integrada en el terreno y con estructura modular y autóctona se creará una arquitectura parasísmica, que evitará posibles desprendimientos en futuros fenómenos ambientales de la zona, como son los terremotos. La terra és un material històricament utilitzat en el mon de l arquitectura. Actualemnte al S.XXI seguim depenen d ell, atès que aquest és un recurs abundant, econòmic i sostenible, aque aporta bones propietats per al seu ús com a material de construcció. És per això que el veiem emprat sobretot, en contectos de subdesenvolupament. El present projecte dóna un gest de complicitat a l arquitectura de cooperació en països en vies de desenvolupament, com és El Salvador, treballant de d un principi en la reconstrucció del caserio de Potrerillos, en Alegria Usulatán. Es prioritza una construcció principalment sostenible, explotant el recurs natural de la terra, i introduint així mateix a l arquitectura en el propi material, treballant d esta forma amb el terme d arquitectura excavada. Mitjançant aquesta construcció integrada al terreny i amb estructrura modular i autoctona es crearà una arquitectura parasísmica, que evitaà possibles despreniments en futurs fenòmens ambientals de la zona, com són els terratrèmols., [EN] Soil is a material historically used in the world of architecture. Currently in the XXI century we continue to depend on it, since this is an abundant, economic and sustainable resource, which provides good properties for use as construction material. That is why we see it used above all, in contexts of underdevelopment. This project gives a nod to the architecture of cooperation in developing countries, such as El Salvador, working from the beginning on the reconstruction of the Potrerillos hamlet, in Alegría Usulután. A mainly sustainable construction is prioritized, exploiting the natural resource of the soil, and introducing architecture in the material itself, thus working with the term excavated architecture. Through this construction integrated into the terrain and with a modular and indigenous structure, a parasismic architecture will be created, which will avoid possible landslides in future environmental phenomena in the area, such as earthquakes.

Els edificis de maçoneria no-reforçada representen un alt percentatge del parc urbà de diverses ciutats com és Barcelona. Actualment aquest tipus d’estructures es troben en contacte directe amb noves estructures de diferent tipus. És per això que és imprescindible determinar el seu comportament estructural amb la finalitat d’avaluar la interacció d’aquests edificis amb les noves estructures i el seu comportament davant fenòmens com els sismes. Mitjançant metodologies simplificades s’obtindran una sèrie de paràmetres representatius que ens permetran determinar la capacitat de l’estructura, que és un dels elements claus que, juntament amb la demanda sísmica, ens permetrien obtenir el desenvolupament de l’estructura davant la demanda. En aquest treball es compararan diversos mètodes simplificats per tal d’avaluar la capacitat de l’estructura i dels quals es selecciona el denominat com a el mètode N2 per a realitzar l’estudi de capacitat. Diverses propietats mecàniques materials (fm, E, G, τ0) s’han seleccionat de manera curosa com a variables aleatòries, representant la variabilitat d’aquest tipus d’edificis, fins a aconseguir una població de 1000 models estructurals. Amb aquest procés s’obtenen les corbes de capacitat de cada model. A través de la selecció d’una mostra suficientment representativa de la població inicial, s’ estableixen relacions y comparatives entre els diferents resultats per tal d’establir la validesa en la utilització de la mostra a manera d’estalviar en recursos de temps i càlcul. Finalment, es presenta un anàlisi de la influència en els diversos resultats de diferents propietats mecàniques materials utilitzades com a variables aleatòries en l’estudi.