124 results on '"Custódio, Susana"'
Search Results
102. The 2004 Mw6.0 Parkfield, California, earthquake: Inversion of near-source ground motion using multiple data sets
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Custódio, Susana, primary, Liu, Pengcheng, additional, and Archuleta, Ralph J., additional
- Published
- 2005
- Full Text
- View/download PDF
103. Tradução, adaptação e validação do Relationship Questionnaire em jovens portugueses.
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Rodrigues Dixe, Maria dos Anjos Coelho, Pereira Catarino, Helena da Conceição Borges, Rodrigues Custódio, Susana Margarida, Figueira Veríssimo, Cristina Maria, Oliveira Fabião, Joana Alice da Silva Amaro, and Alegre de Sá, Maria da Conceição Gonçalves Marques
- Subjects
SERIAL publications - Abstract
Copyright of Revista de Enfermagem Referência is the property of Escola Superior de Enfermagem de Coimbra and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
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104. Translation, adaptation and validation of the Relationship Questionnaire among portuguese young people.
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Rodrigues Dixe, Maria dos Anjos Coelho, Pereira Catarino, Helena da Conceição Borges, Rodrigues Custódio, Susana Margarida, Figueira Veríssimo, Cristina Maria, Oliveira Fabião, Joana Alice da Silva Amaro, and Alegre de Sá, Maria da Conceição Gonçalves Marques
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STATISTICAL correlation ,FACTOR analysis ,INTERPERSONAL relations ,PSYCHOMETRICS ,QUESTIONNAIRES ,RESEARCH evaluation ,JUDGMENT sampling ,RESEARCH methodology evaluation ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
Copyright of Revista de Enfermagem Referência is the property of Escola Superior de Enfermagem de Coimbra and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2014
- Full Text
- View/download PDF
105. Moment Tensor Resolvability: Application to Southwest Iberia.
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Zahradník, Jiří and Custódio, Susana
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EARTHQUAKE hazard analysis ,CALCULUS of tensors ,INVERSE problems ,EARTHQUAKES - Abstract
We present a method to assess the uncertainty of earthquake focal mechanisms based on the standard theory of linear inverse problems. We compute the uncertainty of the moment tensor, M, then map it into uncertainties of the strike, dip, and rake. The inputs are: source and station locations, crustal model, frequency band of interest, and an estimate of data error. The output is a six-dimensional (6D) error ellipsoid, which shows the uncertainty of the individual parameters of M. We focus on the double-couple (DC) part of M. The method is applicable both with and without waveforms. The latter is particularly useful for network design. As an example we present maps of DC resolvability for earthquakes in southwest Europe, computed without waveforms. We find that the resolvability depends critically on frequency range and source depth. Shallow DC sources (10 km) are theoretically better resolved than deeper sources (40 km and 60 km). The DC resolvability of a 40-km-deep event improves considerably when the Portuguese network is supplemented by stations in Spain and Morocco. The DC resolvability can be further improved by using a few ocean bottom seismometer (OBS) stations or a dense land network. A dense land network is able to resolve M well in spite of the large azimuthal gap, which spans ~200°. The theoretical resolution analysis also explains the success of single-station inversions when using a broad frequency range, as exemplified by an application using waveforms of a M
w 6 earthquake offshore Iberia. [ABSTRACT FROM AUTHOR]- Published
- 2012
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106. Fast Kinematic Waveform Inversion and Robustness Analysis: Application to the 2007 MW 5.9 Horseshoe Abyssal Plain Earthquake Offshore Southwest Iberia.
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Custódio, Susana, Cesca, Simone, and Heimann, Sebastian
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CATHODE ray oscillographs ,STRUCTURAL geology ,EARTHQUAKES ,INVERSION (Geophysics) ,ALGORITHMS - Abstract
An M
W 5.9 earthquake occurred beneath the Horseshoe abyssal plain (HAP), offshore southwest Iberia, on 12 February 2007. The region where the earthquake occurred has a high seismogenic and tsunamigenic potential. The purpose of this paper is twofold: (1) to extract information about the source of the earthquake that contributes to the understanding of regional tectonics; and (2) to evaluate the applicability of a fast algorithm to study a moderate earthquake offshore mainland Portugal. We employed the KIWI tools, which implement a multistep inversion algorithm, to infer both the pointand finite-source properties of the earthquake. In order to assess the robustness of our solutions, we performed independent sets of inversions that take different datasets and assumptions (e.g., Green's functions, passbands, wave types) as inputs. We also performed bootstrap analyses in order to appraise the robustness of the source parameters. We concluded that the 2007 HAP earthquake centroid is located at 35.841°N, 10.611°W, at a depth of 39 km. Scalar moment, MO , is consistently retrieved with an average value of 1.00 × 1018 N m (moment magnitude MW 5.9). The finite-fault parameters are difficult to resolve given the existing data. Approximately 70% of our bootstrap solutions indicate a true rupture plane that trends westnorthwest-east-southeast (strike = 128°, dip = 46°, and rake 138°). The location and strike of this fault plane coincide with the southwest Iberian margin (SWIM) faults. However, the 46° dip is difficult to reconcile with the subvertical nature of the SWIM faults. [ABSTRACT FROM AUTHOR]- Published
- 2012
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107. Dynamic modeling of the 2004 Mw 6.0 Parkfield, California, earthquake.
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Ma, Shuo, Custódio, Susana, Archuleta, Ralph J., and Liu, Pengcheng
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- 2008
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108. Kinematic Inversion of the 2004 M 6.0 Parkfield Earthquake Including an Approximation to Site Effects.
- Author
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Pengcheng Liu, Custódio, Susana, and Archuleta, Ralph J.
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EARTHQUAKES ,SEISMIC arrays ,SEISMOGRAMS - Abstract
The 2004 M 6.0 Parkfield earthquake yielded one of the largest amounts of near-source strong ground motion seismic data ever. We invert strong-motion seismograms to obtain a model for the space--time distribution of coseismic slip on the fault. To reduce noise in the inversion, we take into account local amplifications that affect each station by using records of the 1983 M 6.5 Coalinga earthquake. Site amplification correlates well with large peak ground velocities registered during the 2004 Parkfield mainshock. The inversion for a kinematic rupture model yields a nonunique solution: we therefore analyze various rupture models that explain the data equally well. Our preferred rupture model identifies a primary zone of high slip surrounding the hypocenter, where the maximum slip is 57 cm. A secondary slip area. over which contours are not well resolved, is located northwest of the hypocenter. The rupture speed is highly heterogeneous. We infer an average rupture velocity of ∼2.8 km/sec close to the hypocenter, and of ∼3.3 km/sec in the secondary region of large slip to the northwest of the hypocenter. By correlation of our rupture model with both microseismicity and velocity structure, we identify six patches on the fault plane that behave in seismically distinct ways. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
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109. The 2004 Mw6.0 Parkfield, California, earthquake: Inversion of near-source ground motion using multiple data sets.
- Author
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Custódio, Susana, Liu, Pengcheng, and Archuleta, Ralph J.
- Published
- 2005
- Full Text
- View/download PDF
110. A estrutura hierárquica de valores dos psicólogos na lusofonia.
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Cruz, Márcia, Alves, Paulo, Custódio, Susana, Dores, Artemisa R., Mamade, Abiba, Panzo, Ana, and Faleiros, Fernando
- Published
- 2021
111. Coupling between surface deformation and mantle dynamics in the Gibraltar Arc System.
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Civiero, Chiara, Custódio, Susana, Duarte, João, Faccenna, Claudio, Becker, Thorsten, and de Brito Mendes, Virgílio
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DEFORMATION of surfaces , *VERTICAL motion , *SEISMIC tomography , *SHEAR zones , *RAYLEIGH waves , *TOPOGRAPHY - Abstract
We discuss crustal surface velocities in the Gibraltar Arc System derived from around 150 GPS sites in Iberia and Morocco operating between 1995 and 2018. The estimated velocity field shows patterns that are strongly correlated with other geophysical constraints (tomographically imaged velocity anomalies, SKS-splitting, etc.) including seismicity patterns. Broad-scale surface uplift characterizes the Rif-Betics belts, which appear underlain by seismically slow, presumably relatively hot, mantle. Significant rates of subsidence are observed around Cartagena and east of El Hoceima where high-velocity seismic anomalies are imaged in the mantle. This abrupt change of the sign of vertical crustal motions coincides with the location of the Trans-Alboran Shear Zone (TASZ), which is marked by lineaments of mostly strike-slip and trans-tensional shallow earthquakes. We interpret the surface uplift as result of the quasi-toroidal mantle flow induced by the interaction of the retreating Gibraltar slab and the resulting sub-slab upwelling. The part of the Gibraltar slab that is still attached to the crust imaged east of the TASZ may contribute to the observed subsidence rates. The trend of the residual topography also suggests that topography may be controlled in part by mantle-driven processes. Around the Gibraltar slab the contrasting signal between the negative residual topography and positive vertical GNSS data is likely due to the fact that the surface, which was previously depressed by the load of the subduction, is now isostatically recovering. Our results on the Gibraltar Arc System suggest that both surface deformation along the arc and shallow earthquake activity are strongly controlled by coupling between the lithosphere and underlying mantle dynamics. [ABSTRACT FROM AUTHOR]
- Published
- 2019
112. Surface waves dispersion measurements at north of the Gloria fault using seismic ambient noise.
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López, Juan I. Pinzón, Custódio, Susana, Silveira, Graça, Matias, Luis, and Krüger, Frank
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MICROSEISMS , *GREEN'S functions , *GROUP velocity dispersion , *LITHOSPHERE , *OCEAN bottom , *PHASE noise - Abstract
The Gloria fault is a major strike-slip oceanic plate boundary fault, which links the Azores triple junction, in the west, to the oblique convergent boundary between Iberia and NW Africa, in the east. This fault hosted some of the largest strike-slip earthquakes in the oceanic domain, notably the 1941 M8.3 earthquake. In 1975, a M8.1 earthquake hit the intraplate region south of the Gloria fault, in the intersection between an old transform fault and the Madeira-Tore rise. In spite of its seismo-tectonic relevance, the Gloria fault has remained poorly studied, due mostly to its remote location in the north Atlantic.The dataset of the Deep Ocean Test Array (DOCTAR) project encompasses data collected for 10 months at 12 broadband (60-sec) ocean bottom seismometers (OBSs) located about 100 km north of the Gloria fault. This dataset was used to image crustal and mantle discontinuities using receiver function analysis and to infer the S-wave velocity structure of the oceanic lithosphere north of the Gloria fault from P-wave polarization. The seismic structure studies indicate a typical oceanic crustal and mantle structure, influenced by the nearby Gloria fault. In particular, these studies indicate a slight crustal thickening towards the Gloria fault, as well as an increase in uppermost mantle S-wave velocities towards the fault.In this work, we further explore the crustal and uppermost mantle oceanic structure North of the Gloria fault by applying the techniques of ambient noise tomography. We extracted the empirical Green's functions from ambient noise phase cross-correlation (Schimmel et al., 2011), followed by time-frequency phase weighted stack (Schimmel et al., 2007) of continuous seismic and hydrophone data recorded at the array. Our results indicate that the EGFs have a higher signal-to-noise ratio when they are computed from hydrophone-hydrophone or hydrophone-vertical channel data. Pairs of stations oriented NE-SW, show a much highly symmetric cross-correlation on both sides. In HH, HZ, ZH, and ZZ, the record sections highlight a move-out velocity of 1.3 km/s while in the RR and TT shows two different waves with velocities of ~1.3 and 3.2 km/s, respectively. Observed dispersion curves of group velocity over the period range 2 – 25 sec show almost a constant velocity until 15 seconds. After 15 s, we do not obtain reliable dispersion measurements. We compared our results with synthetics computed using a local velocity model, which results from the combination of two different velocity models proposed for the region, and locating the source at 1 m depth in the sediments. The synthetics thus obtained show a good agreement with our observations, suggesting that an ambient noise tomography can be computed from this ocean bottom dataset.The authors acknowledge support from the Portuguese FCT – Fundação para a Ciência e a Tecnologia, I.P., within the scope of project UTAP-EXPL/EAC/0056/2017 and with the FCT grant PD/BD/135069/2017. [ABSTRACT FROM AUTHOR]
- Published
- 2019
113. Did You Feel It? The Ms 7.9 1969 San Vicente Earthquake, 50 Years Later.
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Custódio, Susana, Oliveira, Carlos Sousa, Marreiros, Célia, Alves, Paulo, Carrilho, Fernando, Rodrigues, Diogo, and Weishar, Guilherme
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PALEOSEISMOLOGY , *EARTHQUAKES , *SEISMIC networks , *SEISMOGRAMS , *PLATE tectonics , *EARTHQUAKE magnitude , *SOCIETAL reaction - Abstract
Fifty years ago, on 28 February 1969, at 3:41 local time, an earthquake located offshore SW Iberia strongly shook all the south of Portugal. Maximum intensities of VIII were recorded in the SW tip of Portugal, with intensities VII widespread in the south of Portugal and north of Lisbon. The earthquake was felt up to 1300 km from the epicenter, particularly in Bordeaux, France, and in the Canaries, north Atlantic. With an estimated magnitude of Ms 7.9, this event is currently the highest magnitude felt earthquake in the European historical catalog. One WWSSN seismic station operated in Portugal at the time, in Oporto, while another two seismic observatories (Lisbon and Coimbra) also recorded the earthquake. One strong-motion accelerometer located in the 25th of April bridge, which links Lisbon to the southern margin of the Tagus river, provided the closest non-clipped record of the earthquake. The earthquake occurred at a time when Plate Tectonics was just developing. According to studies carried out in the 70s and 80s, the earthquake, with epicenter in the middle of the Horseshoe Abyssal Plain, had a depth of 22-33 km, Ms 7.9, and the focal mechanism indicates reverse faulting, on a fault striking NE-SW (40 to 70 degrees), a dip of ~50 deg, with a small component of left-lateral faulting. Current microseismic studies indicate that earthquakes in this region frequently occur at depths of ~40 km, indicating brittle failure in the lithospheric mantle, which has classically been attributed to the old and cold nature of the lithosphere in the region. The relationship between instrumental seismicity, historical earthquakes, geologically mapped faults, Earth structure and rheology in this region, which acts as a diffuse plate boundary between the EU and AF plates, and which may have also unleashed the great 1755 Lisbon earthquake, remains enigmatic until today.Taking advantage of the 50th anniversary of this earthquake, of the fact that many citizens still remember well this impressive earthquake, and of currently available technology, a collaborative enterprise between seismologists and engineers, from academic institutions and from the Portuguese seismic network, is launching a Did You Feel It (DYFI) questionnaire for citizens to report back on felt and observed effects of this landmark earthquake that occurred 50 years ago. The resulting macroseismic information will be analyzed with a particular focus on regional attenuation, site effects, and social response of the population. In this presentation, we will review main aspects of this earthquake and report on the first results of the DYFI questionnaire.The authors acknowledge support from the Portuguese FCT – Fundação para a Ciência e a Tecnologia, I.P., within the scope of project SPIDER PTDC/GEO-FIQ/2590/2014 and Instituto Dom Luiz UID/GEO/50019/2019. [ABSTRACT FROM AUTHOR]
- Published
- 2019
114. Stress, suporte social, optimismo e saúde em estudantes de enfermagem em ensino clínico
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Custódio, Susana Margarida Rodrigues, Pereira, Anabela Maria de Sousa, and Seco, Graça Maria dos Santos Batista
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Psicologia individual ,Ensino da enfermagem ,Stresse (Psicologia) ,Alunos do superior ,Psicopatologia - Abstract
Doutoramento em Psicologia O stress é um processo presente nas vivências do quotidiano dos indivíduos com implicações a nível do seu bem-estar e saúde. No caso específico dos estudantes de Enfermagem, o ensino clínico tem sido identificado como uma componente de formação geradora de elevados níveis de stress. O presente estudo tem como principal objectivo analisar as inter-relações que se estabelecem entre a percepção de situações de stress, saúde, coping, suporte social, auto-estima e optimismo-pessimismo. Pretende-se construir e validar dois instrumentos, um de avaliação das situações indutoras de stress em ensino clínico de Enfermagem (ECE) e outro de avaliação dos sintomas de stress. Outro objectivo consiste em traduzir e adaptar duas escalas, uma de avaliação da auto-estima e outra do optimismo-pessimismo. Pretende-se ainda estudar referidos constructos em função de variáveis sócio-demográficas e de caracterização do ensino clínico realizado. O estudo desenvolvido, de natureza quantitativo, correlacional e transversal, baseou-se numa amostra de 1283 estudantes do Curso de Licenciatura em Enfermagem, de cinco Escolas Superiores de Saúde da Região Centro de Portugal. Foi utilizado um protocolo de investigação constituído por 7 instrumentos: Caracterização sócio-demográfica e do ECE, Escala de Stress em ECE, Escala de Sintomas de Stress, Questionário de Estratégias de Coping, Escala de Satisfação com o Suporte Social, Escala de Auto-Estima e Escala de Optimismo-Pessimismo. Os resultados obtidos sugerem que, ao nível das escalas, tanto as construídas no âmbito deste trabalho, como as traduzidas apresentam validade e valores satisfatórios ao nível da fidelidade, constituindo-se então como instrumentos adequados e úteis para o estudo dos constructos em questão. As situações percebidas como geradoras de maior stress referem-se à avaliação, aspectos pessoais e gestão do tempo e do trabalho. Em termos de sintomas de stress, os mais frequentes são de natureza física e cognitivoemocional. Em termos de estratégias de coping, os estudantes parecem recorrer com mais frequência às estratégias centradas nos problemas. Os estudantes da nossa amostra referem uma maior satisfação a nível do suporte social com a intimidade e evidenciam níveis positivos em termos de autoestima e optimismo. O sexo dos estudantes, o ano de frequência do curso e variáveis de caracterização do ECE exercem um efeito diferencial nas problemáticas em estudo. Consideramos que a identificação das situações indutoras de stress em ECE, bem como a avaliação dos seus efeitos na saúde dos estudantes e a compreensão dos mecanismos de coping podem contribuir para o desenvolvimento de programas de gestão e controlo do stress que os capacitem para transformar os desafios em potenciais situações de desenvolvimento pessoal, social, académico e profissional. Stress is a process, which is present in the daily experiences of the individuals with implications at their well-being and health levels. In the specific case of nursing students, clinical teaching has been identified as a training component, which originates high levels of stress. The main objective of the current study is to analyze the relationships established between the perception of stressful situations, health, coping, social support, self-esteem and optimism. It is intended to develop and validate two instruments, one assessing the situations that induce stress in nursing clinical teaching (NCT) and another one evaluating the stress symptoms. A further objective is to translate and adapt two scales, one measuring the selfesteem and another one the optimism-pessimism. It is also deliberate to study these constructs in terms of socio-demographic variables and the characteristics of the conducted clinical teaching. The developed study, of quantitative, correlational and transversal nature, was based on a sample of 1283 students of the Nursing Degree Course, from five Health Superior Schools of the Central Region of Portugal. It was used a research protocol which consists of seven instruments: Sociodemographic and NCT characterization, Stress Scale in NCT, Symptom Scales of Stress, Coping Strategies Questionnaire, Scale of Satisfaction with the Social Support, Self-Esteem Scale and Optimism-Pessimism Scale. The obtained results suggest that, in terms of scale, both the constructed in this work, as well as the translated exhibit validity and acceptable values in terms of fidelity, being considered suitable and useful for the study of the constructs in question. The situations considered as the source of greater stress are correlated to the assessment, personal aspects and time and work management. In terms of stress symptoms, the most common are of physical and cognitive-emotional nature. In terms of coping strategies, students seem to resort more often to strategies focused on problems. Our sample students report a higher level of contentment with social support and intimacy and illustrate positive levels in self-esteem and optimism terms. The students’ gender, the course’s year and characterization variables of the NCT have a differential effect on the problems being studied. We believe that the identification of the situations that induce stress in NCT, as well as the assessment of their effects on the students’ health and the understanding of coping mechanisms may contribute to the development of management and stress control programmes that enable them to transform challenges into potential situations of personal, social, academic and professional development.
115. Dynamic earthquake triggering in southeast Africa.
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Neves, Miguel, Custódio, Susana, and Zhigang Peng
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EARTHQUAKES - Published
- 2018
116. Active deformation in Iberia: The role of gravitational potential energy.
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Custódio, Susana, Neres, Marta, Neves, Conceição, Palano, Mimmo, Fernandes, Rui, Matias, Luis, Carafa, Michele, and Terrinha, Pedro
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GRAVITATIONAL potential - Published
- 2018
117. Mantle upwellings below the Ibero-western Maghrebian region: constraints from teleseismic traveltime P- and S-wave tomography.
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Civiero, Chiara, Strak, Vincent, Custódio, Susana, Silveira, Graça, Rawlinson, Nicholas, and Arroucau, Pierre
- Published
- 2018
118. Magnetic evidence for a Cretaceous intrusion underlying the Gudalquivir - Portimão Banks (Gulf of Cadiz).
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Neres, Marta, Terrinha, Pedro, Custódio, Susana, Silva, Sónia Manzoni, Luis, Joaquim, and Miranda, J. Miguel
- Published
- 2018
119. Erratum to Kinematic Inversion of the 2004 M 6.0 Parkfield Earthquake Including an Approximation to Site Effects.
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Pengcheng Liu, Custódio, Susana, and Archuleta, Ralph J.
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EARTHQUAKES - Abstract
A correction to the article "Kinematic Inversion of the 2004 M 6.0 Parkfield Earthquake Including an Approximation to Site Effects" that was published in a previous issue is presented.
- Published
- 2008
- Full Text
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120. Seismic sequences induced by water loads in Azores
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Dias, Ana Laura Lordi, Neves, Maria C., and Custódio, Susana
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Seismicity ,Seasonal modulations ,Hydrological loads ,Azores ,Ciências Naturais::Outras Ciências Naturais [Domínio/Área Científica] - Abstract
Em diversas partes do mundo já foi observado o aumento da taxa de sismicidade associada aos efeitos de cargas hidrológicas na crosta (Bollinger et al. 2007; Craig et al. 2017; Dumont et al. 2020). Desta forma, este trabalho investiga a conexão entre cargas atmosféricas e hidrológicas e a deformação crustal na região dos Açores, procurando por modulações sazonais e inter-anuais na taxa de ocorrência de sismos, que podem ser causadas pela variação atmosférica e hidrológica. O presente estudo envolve a manipulação e o declustering do catálogo sísmico dos Açores, de 2008 a 2018 e uma análise estatística dos dados. A metodologia utilizada nos dados dos Açores foi primeiro testada no sistema de falhas de Nova Madrid (EUA), seguindo o artigo de Craig et al. 2017, onde foi descoberta uma conexão entre o aumento da sismicidade e a baixa taxa de chuva no final do Verão. Isto ocorre, pois durante o Inverno, a carga hidrológica do rio Mississippi que é cortado pelo sistema de falhas exerce pressão sobre a crosta. Durante o Verão, a crosta soergue devido ao alívio de carga e então desencadeia uma alta atividade sísmica. Os resultados obtidos neste trabalho se mostraram compatíveis aos resultados encontrados pelo autor. Sendo assim, a metodologia utilizada foi aplicada aos Açores. A análise dos dados dos Açores foi realizada separadamente, para a região oceânica e para as ilhas, já que diferentes processos físicos ocorrem em ambos locais. As ilhas sofrem com as marés terrestres, precipitação e variação nas águas subterrâneas, enquanto o oceano sofre com o peso da coluna d’água. Assim, de forma a analisar melhor a sazonalidade e os possíveis mecanismos atuantes, o catálogo foi divido. A janela temporal dos dados (de 2008 a 2018) foi escolhida de forma que mudanças nas redes sísmicas e trocas de equipamento não afetassem os dados. O primeiro passo neste estudo foi eliminar eventos sísmicos dependentes de um evento principal, através de um processo chamado declustering, de modo que apenas restasse os eventos independentes, chamados de mainshocks. O declustering é essencial na análise de sazonalidade dos dados, já que eventos dependentes poderiam tendenciar os dados. Antes da análise de sazonalidade, foi calculada a razão entre o número de eventos que ocorrem nos meses de Inverno e aqueles que ocorrem nos meses de Verão. Esta razão mostrou que mais eventos estavam ocorrendo no Verão quando comparados com o período de Inverno. Na análise de sazonalidade foram empregues métodos estatísticos como a simulação de Monte Carlo e a abordagem Jack-Knife. A simulação de Monte Carlo foi utilizada para gerar 10 mil catálogos aleatórios baseados nos catálogos originais. A razão Inverno/Verão de cada um dos 10 mil catálogos foi calculada assim como os intervalos de confiança de 99% e 95%, com a finalidade de se observar uma razão Inverno/Verão ao acaso semelhante à razão observada. Os resultados desta análise mostraram que para a sismicidade oceânica, considerando os intervalos de magnitude de 2.0 a 2.7 e de 3.5 a 4.8, a probabilidade de se observar a mesma razão Inverno/Verão é menor que 1%, confirmando que a sazonalidade é genuína. Já para as ilhas, a razão Inverno/Verão caiu dentro dos intervalos de confiança, o que indica que a sazonalidade está ocorrendo por acaso. A abordagem de Jack-Knife, foi realizada para confirmar os resultados obtidos na simulação. Durante esta etapa, todo o processo anterior de geração dos 10 mil catálogos e cálculo das razões é repetido, mas agora removendo ano a ano dos dados, um de cada vez. Esta abordagem permite identificar eventos climáticos extremos que podem ter ocorrido durante os anos e interferiram na sazonalidade. Não foram encontrados eventos anômalos para região oceânica, confirmando que ao longo de 11 anos a sazonalidade se mostrou genuína. Sendo assim, a taxa sísmica oceânica mensal foi calculada e comparada com as séries temporais mensais de precipitação, altura total das ondas, pressão atmosférica e pressão média ao nível do mar. As componentes principais que mais contribuem para cada série temporal foram escolhidas durante a Análise Espectral Singular, que decompõe e reconstrói os sinais das séries, em seguida correlacionadas com as componentes principais da taxa sísmica. Os resultados da correlação mostraram que a taxa sísmica oceânica está correlacionada negativamente com a taxa de precipitação por um coeficiente de correlação de -0.69, por -0.77 com a altura total das ondas, e positivamente com a pressão atmosférica (0.40) e com a pressão a nível do mar (0.39). Em sequência, foi realizado o teste de t-student, que confirmou que os resultados da correlação são significativos. Os resultados deste estudo demonstram que a modulação sazonal da taxa de sismicidade oceânica é presente em cada ano (de 2008 a 2018). Assim como no sistema de falhas de Nova Madrid, a taxa de sismicidade oceânica dos Açores é maior durante o Verão (nos meses de J-A-S-O) e menor durante o Inverno (nos meses de J-F-M-A). Estudos futuros devem focar em quantificar as tensões causadas pelas cargas hidrológicas mencionadas, a fim de que se confirme a influência delas na sismicidade, além de investigar outros possíveis mecanismos, como as marés. Os resultados fornecem uma avaliação de variações cíclicas na sismicidade e sua relação com perturbações hidrológicas e atmosféricas na região dos Açores. Além disso, proporciona uma primeira abordagem da precipitação e da altura total das ondas como possíveis mecanismos de desencadeamento da atividade sísmica oceânica na região, contribuindo para melhorar a nossa compreensão sobre os mecanismos de desencadeamento dos sismos em sistemas vulcano-tectônicos ativos e para a previsão de períodos onde há aumento da sismicidade. This work investigates the connection between atmospheric and hydrological loads and crustal deformation in the Azores region, looking in particular for seasonal and inter-annual modulations of the earthquake occurrence rate which can be caused by atmospheric and hydrological variations. The work involves the manipulation and declustering of the Azores seismic catalogue, from 2008 to 2018, and statistical analysis of the data. The New Madrid Seismic Zone (NMSZ, USA), where a connection between enhanced seismicity and low rainfall rate in late summer had already been recognized, is used as a benchmark study site to test the methodology. The analysis of the Azores data was carried out separately, for the oceanic region and for the islands, and also considering earthquakes with magnitude above 2.0 (the magnitude of completeness). Just as for the NMSZ, the oceanic seismicity rate of the Azores is higher during Summer/fall (J-A-S-O months) and lower during Winter/Spring (J-F-M-A months). Monte Carlo simulations, used to check if the seasonal and inter-annual variations found in the seismicity pattern are statistically significant and not observed by chance, show that the probability of observing such seasonality by chance is less than 1% for magnitude bands from 2.0 to 2.7 and from 3.8 to 4.5. The influence of extreme climatic events is investigated using a Jack-knife approach. The results demonstrate that the seasonal modulation of the ocean seismicity rate is present at each calendar year (from 2008 to 2018) and is not the consequence of single extreme climatic deviations. Unlike the ocean region, where the seasonality is more evident and genuine in both catalogues, the islands presented a seasonality that was statistically genuine only in the full catalogue. The study of the seasonal modulation investigated using methods of decomposition and reconstruction of geophysical time series (SSA – Singular Spectrum Analysis) show that the principal components of the Azores ocean seismicity rate is negatively correlated with the principal components of rainfall (-0.69) and the significant height of wind waves and swell (-0.77) and positively correlated with atmospheric pressure (0.40) and mean sea level pressure (0.39). The results provide a first assessment of cyclic variations in seismicity and its relationship with atmospheric and hydrological disturbances in the Azores region.
- Published
- 2021
121. Seismicity of the gulf of Cadiz: insights from the joint analysis of OBS and land seismic data
- Author
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Bolrão, Daniela Sofia Da Paz and Custódio, Susana Inês da Silva,1979
- Subjects
Teses de mestrado - 2016 ,Golfo de Cádis ,Aglomerados ,Detecções ,Sismos ,Localizações 3D ,Ciências Naturais::Outras Ciências Naturais [Domínio/Área Científica] - Abstract
Tese de mestrado em Ciências Geofísicas, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2016-12-09T16:24:51Z No. of bitstreams: 1 ulfc120676_tm_Daniela_Bolrão.pdf: 16095079 bytes, checksum: 30bbac66bf1de41a21c46e047de2f9f1 (MD5) Made available in DSpace on 2016-12-09T16:25:10Z (GMT). No. of bitstreams: 1 ulfc120676_tm_Daniela_Bolrão.pdf: 16095079 bytes, checksum: 30bbac66bf1de41a21c46e047de2f9f1 (MD5) Previous issue date: 2016
- Published
- 2016
122. Geração seniores em rede: o facebook como promotor de um envelhecimento ativo
- Author
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Reis, Margarida Ferreira, Ribeiro, Jaime Emanuel Moreira, and Custódio, Susana Margarida Rodrigues
- Subjects
Facebook ,Redes sociais ,Ciências Médicas::Ciências da Saúde [Domínio/Área Científica] ,Solidão ,Seniores - Abstract
O envelhecimento demográfico é uma realidade incontornável da sociedade contemporânea. Uma vida longa não significa necessariamente uma vida boa. Para que o aumento da longevidade adquira sentido, importa criar condições para que as pessoas idosas tenham qualidade de vida, considerando o seu bem-estar, funcionalidade e integração numa sociedade que se apresenta em constante mudança. O Facebook é uma rede social que rapidamente se tornou, não só um canal de comunicação, mas também um destino de inúmeros utilizadores para procura de socialização, informação, partilha ou aprendizagem. Face à ubiquidade de que se reveste o Facebook e face à problemática do envelhecimento estudou-se a utilização da rede social Facebook como forma de combate ao isolamento e à promoção da rede de laços familiares dos seniores. O estudo procurou ainda: avaliar o grau de solidão dos inquiridos; conhecer a utilização da rede social Facebook pelos seniores; e analisar os interesses e motivações relativamente ao uso desta rede. Tendo subjacente os constructos em estudo optou-se por uma metodologia de abordagem quantitativa e qualitativa. Com um objetivo descritivo-correlacional configura-se num levantamento/inquérito (survey), sendo a aquisição de dados realizada através de questionário online que integra a Escala da Solidão da UCLA e a realização de entrevistas semiestruturadas a voluntários respondentes do questionário inicial. A amostra do estudo é constituída por 269 indivíduos distribuídos pelo território português, com idade igual ou superior a 55 anos, aposentados e utilizadores do Facebook. A validação do questionário foi concretizada por consulta a especialistas e através de uma pilotagem 10 seniores, seguindo-se o método de respondente debriefing, de modo a verificar a compreensibilidade e clareza das questões e eventuais dificuldades sentidas no preenchimento do questionário. Observa-se que a maioria dos respondentes usa esta rede como meio de socialização, assim como para comunicar com conhecidos e familiares. Para este público, o Facebook emerge como fonte de novos conhecimentos, comunicação e para procura, partilha ou aprendizagem. Surge como um refúgio contra a solidão e um canal de ligação a familiares mais distantes. Apesar de todas as vantagens e desvantagens, benefícios e perigos, os seniores recorrem a esta rede social, ainda que muitas vezes criem amizades “sem rede”, dado as mesmas serem através de um ecrã. Foi possível verificar que a rede social Facebook ajuda a combater o isolamento e auxilia a rede de laços familiares e sociais, conduzindo assim a um envelhecimento ativo.
123. Dynamic triggering of seismic activity in rifting and volcanic settings
- Author
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Neves, Miguel João Góis Ferreira Gaspar and Custódio, Susana Inês da Silva,1979
- Subjects
Teses de mestrado - 2016 ,Ondas de superfície ,Estatística β ,Dynamic triggering ,Tremor ,Ciências Naturais::Outras Ciências Naturais [Domínio/Área Científica] - Abstract
Tese de mestrado em Ciências Geofísicas, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2016-12-12T15:44:47Z No. of bitstreams: 1 ulfc118869_tm_Miguel_Neves.pdf: 17540797 bytes, checksum: 86cc51486958bc67f39a0f7352761d6e (MD5) Made available in DSpace on 2016-12-12T15:44:58Z (GMT). No. of bitstreams: 1 ulfc118869_tm_Miguel_Neves.pdf: 17540797 bytes, checksum: 86cc51486958bc67f39a0f7352761d6e (MD5) Previous issue date: 2016
124. Caracterização da actividade sísmica de Monchique
- Author
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Soares, Analdyne Mandinga da Cruz and Custódio, Susana Inês da Silva,1979
- Subjects
Localização Hipocentral ,Correlação cruzada ,Teses de mestrado - 2018 ,Monchique ,Ciências Naturais::Ciências da Terra e do Ambiente [Domínio/Área Científica] ,NonLinLoc - Abstract
Tese de mestrado em Ciências Geofísicas, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, em 2018 Submitted by Cristina Manessiez (camanessiez@fc.ul.pt) on 2018-11-29T19:11:19Z No. of bitstreams: 1 ulfc121885_tm_Analdyne_Soares.pdf: 17400088 bytes, checksum: 78122a10642e3acf333e6b93b1d10534 (MD5) Made available in DSpace on 2018-11-29T19:11:31Z (GMT). No. of bitstreams: 1 ulfc121885_tm_Analdyne_Soares.pdf: 17400088 bytes, checksum: 78122a10642e3acf333e6b93b1d10534 (MD5) Previous issue date: 2018
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