Assessing shallow landslide hazards using the TRIGRS and SHALSTAB models,Serra do Mar,Brazil     

Bianca Carvalho Vieira  Nelson Ferreira Fernandes  Oswaldo Augusto Filho  Tiago Damas Martins  David R. Montgomery 《Environmental Earth Sciences》2018,77(6):260

The hillslopes of the Serra do Mar, a system of escarpments and mountains that extend more than 1500 km along the southern and southeastern Brazilian coast, are regularly affected by heavy rainfall that generates widespread mass movements, causing large numbers of casualties and economic losses. This paper evaluates the efficiency of susceptibility mapping for shallow translational landslides in one basin in the Serra do Mar, using the physically based landslide susceptibility models SHALSTAB and TRIGRS. Two groups of scenarios were simulated using different geotechnical and hydrological soil parameters, and for each group of scenarios (A and B), three subgroups were created using soil thickness values of 1, 2, and 3 m. Simulation results were compared to the locations of 356 landslide scars from the 1985 event. The susceptibility maps for scenarios A1, A2, and A3 were similar between the models regarding the spatial distribution of susceptibility classes. Changes in soil cohesion and specific weight parameters caused changes in the area of predicted instability in the B scenarios. Both models were effective in predicting areas susceptible to shallow landslides through comparison of areas predicted to be unstable and locations of mapped landslides. Such models can be used to reduce costs or to define potentially unstable areas in regions like the Serra do Mar where field data are costly and difficult to obtain.  相似文献   

Coastal erosion risk assessment to discuss mitigation strategies: Barra-Vagueira,Portugal     

Ferreira  A. M.  Coelho  C.  Narra  P. 《Natural Hazards》2021,105(1):1069-1107

Natural Hazards - Worldwide coastal zones present serious erosion problems that cause loss of territory. This phenomenon exposes people and goods to the threat, being necessary to carry out a...  相似文献   

Timing of Proterozoic magmatism in the Sunsas belt,Bolivian Precambrian Shield,SW Amazonian Craton     

Ingrid M.Nedel  Reinhardt A.Fuck  Amarildo S.Ruiz  Gerardo R.Matos-Salinas  Alanielson da C.D.Ferreira 《地学前缘(英文版)》2021,12(6):277-293

We present new U-Pb zircon and monazite ages from the Sunsas belt granitic magmatism in Bolivia,SW Amazonian Craton.The geochronological results revealed four major magmatic events recorded along the Sunsas belt domains.The older igneous event formed a granitic basement coeval to the Rio Apa Terrane(1.95-1.85 Ga)in the southern domain.The second magmatic episode is represented by 1.68 Ga granites associated to the Paraguá Terrane(1.69-1.66 Ga)in the northern domain.The 1.37-1.34 Ga granites related to San Ignacio orogeny represent the third and more pervasive magmatic event,recorded throughout the Sunsas belt.Moreover,magmatic ages of～1.42 Ga revealed that the granitogenesis asso-ciated to the Santa Helena orogeny also affected the Sunsas belt,indicating that it was not restricted to the Jauru Terrane.Lastly,the 1.10-1.04 Ga youngest magmatism was developed during the Sunsas oro-geny and represents the final magmatic evolution related to Rodinia assembly.Likewise,the 1.95-1.85 and 1.68 Ga inherited zircon cores obtained in the～1.3 Ga and 1.0 Ga granite samples suggest strong par-tial melting of the Paleoproterozoic sources.The 1079±14 Ma and 1018±6 Ma monazite crystallization ages can be correlated to the collisional tectono-thermal event of the Sunsas orogeny,associated to reac-tions of medium-to high-grade metamorphism.Thus,the Sunsas belt was built by heterogeneous 1.95-1.85 Ga and 1.68 Ga crustal fragments that were reworked at 1.37-1.34 Ga and 1.10-1.04 Ga related to orogenic collages.Furthermore,the 1.01 Ga monazite age suggests that granites previously dated by zir-con can bear evidence of a younger thermal history.Therefore,the geochronological evolution of the Sunsas belt may have been more complex than previously thought.  相似文献   

A spatiotemporal calculus for reasoning about land-use trajectories   总被引：1，自引：0，他引：1  

Adeline Marinho Maciel  Gilberto Camara  Lubia Vinhas  Michelle Cristina Araújo Picoli  Rodrigo Anzolin Begotti  Luiz Fernando Ferreira Gomes de Assis 《International journal of geographical information science》2019,33(1):176-192

Earth observation images are a powerful source of data about changes in our planet. Given the magnitude of global environmental changes taking place, it is important that Earth Science researchers have access to spatiotemporal reasoning tools. One area of particular interest is land-use change. Using data obtained from images, researchers would like to express abstractions such as ‘land abandonment’, ‘forest regrowth’, and ‘agricultural intensification’. These abstractions are specific types of land-use trajectories, defined as multi-year paths from one land cover into another. Given this need, this paper introduces a spatiotemporal calculus for reasoning about land-use trajectories. Using Allen’s interval logic as a basis, we introduce new predicates that express cases of recurrence, conversion and evolution in land-use change. The proposed predicates are sufficient and necessary to express different kinds of land-use trajectories. Users can build expressions that describe how humans modify Earth’s terrestrial surface. In this way, scientists can better understand the environmental and economic effects of land-use change.  相似文献   

Hazard assessment in rock cliffs at Central Algarve (Portugal): A tool for coastal management     

M. Nunes   . Ferreira  M. Schaefer  J. Clifton  B. Baily  D. Moura  C. Loureiro 《Ocean & Coastal Management》2009,52(10):506-515

Coastal hazards are in the interface of human activities with natural coastal processes. The conflicts arising from this relationship require new approaches suitable for coastal management that consider the dynamic of coastal areas. A method to assess hazard in rock cliffs is presented, combining cliff evolution forcing mechanisms along with protection factors, according to a weighted factors system. This method provides a rapid evaluation of vulnerability for cliffed areas, supporting coastal management and hazard mitigation. The method was applied to the rocky cliffs of the densely populated coastal zone between Galé and Olhos de Água (Southern Portugal), where high and very high hazard values were found to be dominant. A method validation was made using the vulnerability areas and the recorded mass movements over a 45 year period in the same area.  相似文献   

Analytical study of the swing-by maneuver in an elliptical system     

Alessandra F. S. Ferreira  Antônio F. B. A. Prado  Othon C. Winter  Denilson P. S. Santos 《Astrophysics and Space Science》2018,363(2):24

The objective of the present paper is to derive a set of analytical equations that describe a swing-by maneuver realized in a system of primaries that are in elliptical orbits. The goal is to calculate the variations of energy, velocity and angular momentum as a function of the usual basic parameters that describe the swing-by maneuver, as done before for the case of circular orbits. In elliptical orbits the velocity of the secondary body is no longer constant, as in the circular case, but it varies with the position of the secondary body in its orbit. As a consequence, the variations of energy, velocity and angular momentum become functions of the magnitude and the angle between the velocity vector of the secondary body and the line connecting the primaries. The “patched-conics” approach is used to obtain these equations. The configurations that result in maximum gains and losses of energy for the spacecraft are shown next, and a comparison between the results obtained using the analytical equations and numerical simulations are made to validate the method developed here.  相似文献   

The role of shoshonitic and calc-alkaline suites in the tectonic evolution of the Carajás District, Brazil     

M.A. Dardenne  C.F. Ferreira Filho  M.R. Meirelles 《Journal of South American Earth Sciences》1988,1(4)

In the Carajás District, the Bahia Prospect and Grão Pará volcanosedimentary sequences, both of Archean age, have been the object of extensive petrochemical studies for major, trace, and rare earth elements. In spite of the widespread spilitization that affected the volcanic mafic rocks, the petrochemical nature of the mafic volcanism may still be assessed on the basis of the less mobile elements like P, Cr, Zr, Nb, Ti, and REE. The Bahia Prospect basalts have a petrochemical affinity with Phanerozoic island-arc calc-alkaline basalts. The Grão Pará basalts and basaltic andesites, on the other hand, have a petrochemical affinity with Phanerozoic basalts of a mature island arc environment. The petrochemical data presented here lead to a new geotectonic interpretation of the area, where the volcanic sequences are genetically linked to Archean subduction processes.  相似文献   

Biogeochemistry of the Madeira river basin     

Dr. J. Mortatti  Dr. J. R. Ferreira  Dr. L. A. Martinelli  Dr. R. L. Victoria  A. C. F. Tancredi 《GeoJournal》1989,19(4):391-397

A biogeochemical characterization of the Madeira river basin has been made to evaluate the local and global effects of possible alterations in the ecosystem caused by recent intensive occupation in Rondonia state. During the period April 1983—January 1986, sampling was made both by land and river along the tributaries and main channel of the Madeira river. The parameters analysed lead to a detailed study of the physicochemical quality of the waters of the basin and their relationship with the local geology, associated with the transport of solid material and the hydrological behavior of the ecosystem.Penman's method adapted to tropical rainforest conditions was used to evaluate the potential evapotranspiration for the basin. Estimated potential evapotranspiration was 1420 mm/y, 77% due to the energy balance. Real evapotranspiration was 94% of the estimated potential and the main residence time of the rain water in the basin was 2 months. The isotopic behavior of Hydrogen and Oxygen in the river waters of the region was typical of great rivers, the values being more positive during the dry season and more negative during the rainy season. An isotopic gradient of ¹⁸O 0.038 ()/100 km, was established from Porto Velho station to the estuary, which was considered low when compared with the value of 0.063 ()/100 km, obtained for the Amazon river.In general, the waters of the tributaries were poor in dissolved ion species when compared with the main channel of the Madeira river. Seasonal variation in the transport of suspended sediment kept the same pattern, greater transport being observed on rising water than during high water. A transport of 2.85 million tons per day was observed in the Madeira river near the mouth.  相似文献   

North Atlantic Oscillation sensitivity to the El Niño/Southern Oscillation polarity in a large-ensemble simulation     

P. Melo-Gonçalves  A. C. Rocha  J. M. Castanheira  J. A. Ferreira 《Climate Dynamics》2005,24(6):599-606

A large ensemble modeling experiment with the Melbourne University General Circulation Model is presented. Thirty 17-year-long independent simulations were performed. All integrations were forced by the same observed sea surface temperatures, obtained from the Atmospheric Model Intercomparison Project II. The simulations were analyzed to assess the sensitivity of the North Atlantic Oscillation (NAO) to the El Niño/Southern Oscillation (ENSO) polarity. The results show signals of the ENSO phases both in the mean strength of the NAO as well as in its internal variability. During the cold ENSO phase, the probability density function of the NAO index presents a small but positive mean value, whereas it is negative during the warm ENSO phase. Also, the NAO variability associated with each ENSO phase shows a different behavior: during the warm phase the probability density function of the NAO index presents a larger variance and suggests a bimodality, whereas no bimodality is suggested in the cold phase.  相似文献   

Aquifer development planning to supply a seaside resort: a case study in Goa,India     

J. P. Cárcomo Lobo Ferreira  Maria da Conceição Cunha  A. G. Chachadi  Kai Nagel  Catarina Diamantino  Manuel Mendes Oliveira 《Hydrogeology Journal》2007,15(6):1147-1155

Using the hydrogeological and socio-economic data derived from a European Commission research project on the measurement, monitoring and sustainability of the coastal environment, two optimization models have been applied to satisfy the future water resources needs of the coastal zone of Bardez in Goa, India. The number of tourists visiting Goa since the 1970s has risen considerably, and roughly a third of them go to Bardez taluka, prompting growth in the tourist-related infrastructure in the region. The optimization models are non-linear mixed integer models that have been solved using GAMS/DICOPT++ commercial software. Optimization models were used, firstly, to indicate the most suitable zones for building seaside resorts and wells to supply the tourist industry with an adequate amount of water, and secondly, to indicate the best location for wells to adequately supply pre-existing hotels. The models presented will help to define the optimal locations for the wells and the hydraulic infrastructures needed to satisfy demand at minimum cost, taking into account environmental constraints such as the risk of saline intrusion.

---

Résumé A l’aide de données hydrogéologiques et socio-économiques, dérivées d’un projet de recherche de la Commission Européenne sur l’étude, la surveillance et la durabilité de l’environnement c?tier, deux modèles d’optimisation ont été appliqués en vue de satisfaire les besoins futurs en ressources en eau de la zone c?tière de Bardez au Goa en Inde. Le nombre de touristes qui visitent le Goa depuis les années 70 a considérablement augmenté et environ un tiers d’entre eux se rend à Bardez taluka, ce qui encourage la croissance des infrastructures liées au tourisme dans la région. Les modèles d’optimisation sont des modèles non linéaires mixtes en nombres entiers qui ont été résolus en utilisant le logiciel commercial GAMS/DICOPT++. Les modèles d’optimisation ont été utilisés pour indiquer premièrement les zones les plus appropriées pour construire des stations balnéaires et des puits pour approvisionner en quantité d’eau suffisante l’industrie touristique, et deuxièmement pour indiquer la meilleure localisation de puits pour l’alimentation des h?tels préexistants. Les modèles présentés aideront à définir les localisations optimales des puits et des infrastructures hydrauliques nécessaires à la satisfaction de la demande à un co?t minimum, tout en prenant en compte les contraintes environnementales, tel que le risque d’intrusion saline.

---

Resumen Se han aplicado dos modelos de optimización en base a datos socio-económicos e hidrogeológicos derivados de un proyecto de investigación de la Comisión Europea sobre medición, monitoreo y sostenibilidad del ambiente costero para satisfacer las necesidades futuras de recursos hídricos de la zona costera de Bardez en Goa, India. El número de turistas que visita Goa desde la década de 1970′s ha subido considerablemente y cerca de un tercio de ellos van a Bardez taluka impulsando el crecimiento en la infraestructura turística de la región. Los modelos de optimización son modelos de números enteros mixtos no-lineales que se han resuelto usando el programa comercial GAMS/DICOPT++. Los modelos de optimización se usaron, primero para indicar las zonas más adecuadas para la construcción de centros de diversión en las márgenes del océano y pozos para abastecer la industria turística con una adecuada cantidad de agua, y segundo, para indicar la mejor localización de pozos para el abastecimiento de hoteles pre-existentes. Los modelos que se presentan ayudarán a definir las localizaciones óptimas para los pozos y las infraestructuras hidráulicas necesarias para satisfacer la demanda al mínimo costo, tomando en consideración restricciones ambientales tal como el riesgo de intrusión salina.

  相似文献