Geoelectric Subsurface Characterization in the Emerged Portion of the Barra Falsa Channel using the Ground Conductivity Meter (LIN-EM), Bojuru, RS, Brazil José Pedro Rebés Lima, Iran Carlos Stalliviere Corrêa, Jair Weschenfelder, Marco Antonio Fontoura Hansen, Nelson Luis Sambaqui Gruber Sambaqui Gruber, et al. Geofisica Internacional, 2025 Geophysical investigation in the coastal region of the emerged portion of Barra Falsa, Bojuru, RS, Brazil, provided valuable information about the depositional evolution and paleoenvironmental changes that occurred during the Quaternary period. The combination of electromagnetic surveys, analysis of stratigraphic wells, 3.5 kHz reflection seismic and previous geological data allowed for a comprehensive characterization of sedimentary environments associated with sea-level fluctuations. Electromagnetic surveys using the LIN- EM method with the Geonics EM34TM system revealed different conductivity responses in the subsurface, which could be interpreted in relation to depositional events. Five depth intervals were identified and related to specific events, such as the closure of the Barra Falsa channel, estuarine infilling, and channel drowning during marine transgressions. Furthermore, the comparison of the results of electromagnetic surveys with data from stratigraphic wells allowed calibration of indirect data. This multidisciplinary approach highlights the importance of integrating geophysical and geological techniques to reconstruct coastal environment evolution over time. This study provides a detailed insight into paleoenvironmental and depositional changes on the coast of Bojuru, demonstrating how these techniques can significantly contribute to future research and the sustainable management of coastal areas. The knowledge gained here is essential for understanding the dynamics of coastal zones and the influences of sea-level variations in the Southern region of Brazil.
Beach certification schemes in Latin America: Are they applicable to the Brazilian context? Luidgi Marchese, Camilo M. Botero, Seweryn Zielinski, Giorgio Anfuso, Marcus Polette, et al. Sustainability Switzerland, 2021 Beaches are multidimensional ecosystems that develop relevant natural functions and host tourist activities of great economic value. Therefore, they are currently being subjected to severe human pressure and natural impacts often enhanced by climate change. Beach certification schemes (BCSs) were designed to bridge the gap between recreation and conservation uses. The aim of this paper is to assess the compatibility and potential contribution of nine Beach Classification Schemes (BCSs) used in Latin America with the Orla Project implemented in Brazil to optimize land use planning of coastal zones, including beaches. The weaknesses and strengths of each BCSs were assessed according to the criteria for integrated coastal zone management. As a result, four of the nine BCSs were found to be the most compatible with the context of Brazilian beaches (Ecuadorian, Colombian, Cuban, and Argentinean BCSs), indicating that BCSs can contribute to specific aspects of beach management, but they should not be the only management strategy. In conclusion, the strengths of the four BCSs identified in this study can be used to build a new management tool for Brazilian beaches aligned with the Orla Project—the main coastal planning and management instrument currently used.
Validation of the digital elevation model (SRTM) with gnss surveying applied to the mirim lagoon hydrographic basin Patricia Andréia Paiola Scalco, Andrea Lopes Iescheck, Iran Carlos Stalliviere Corrêa, Fernando Comerlato Scottá, Rafael Mastracusa de Oliveira, et al. Boletim De Ciencias Geodesicas, 2018 Between 2013 and 2014, a kinematic positioning based on the Global Navigation Satellite System (GNSS) was carried out for this research work. This GNSS survey resulted in 275916 points with tridimensional coordinates in the cross-border basin area of 58205 km2 called Mirim Lagoon Hydrographic Basin, located in south of Rio Grande do Sul (Brazil) and west of Uruguay. This study aims at showing the methodology firstly and, furthermore, results regarding the validation of the vertical accuracy of the DEM SRTM through kinematic positioning by GNSS, in the Mirim Lagoon Hydrographic Basin region. Also, the GNSS surveying data was post-processed with the Precise Point Positioning (PPP) method, and the ellipsoidal height was converted into orthometric height through the software INTPT geoid. During this study, the geopotential model (EGM96) was used to transform altitude differences between two countries, Brazil and Uruguay. Results showed that the vertical mean absolute error of the DEM SRTM vary from 0.07 m to ± 9.9m with average of -0.28m. This vertical accuracy is better than the absolute vertical accuracy value of ±16m published in the SRTM data specification and validates the DEM SRTM.
Shallow gas features and distribution in the patos lagoon: A coastal trap for gas-generator sediments Jair WESCHENFELDER, Iran Carlos Stalliviere Carlos Stalliviere CORRÊA Pesquisas Em Geociencias, 2018 Aspectos e distribuição de gás raso na Lagoa dos Patos: um trape costeiro para sedimentos geradores de gás. Sedimentos gasosos são muito comuns nos ambientes costeiros em todo o mundo e suas ocorrências são claramente reveladas como anomalias acústicas por diversas ferramentas sísmicas, em diferentes escalas e resoluções. Este artigo apresenta exemplos de anomalias acústicas relacionadas ao gás, em perfis sísmicos (SBP) de alta resolução da Lagoa dos Patos, Sul do Brasil. Os ecogramas mostram anomalias acústicas devidas ao gás, as quais podem apresentar uma morfologia distinta para gás aprisionado no sedimento, percolação ou gás livre na coluna de água. As depressões topográficas pretéritas preenchidas com sedimentos gasosos são relacionadas aos antigos sistemas de drenagem, desenvolvidos na região costeira devido às oscilações do nível do mar durante o Quaternário. Assim, essas ocorrências de gás raso parecem ser controladas pela configuração paleoambiental, arranjo de preenchimento da bacia de sedimentação e condições hidrodinâmicas. Desde o estabelecimento da configuração atual, após o período de nível do mar alto do Holoceno, o interior da lagoa de Patos comporta-se como uma armadilha costeira para sedimentos finos, ricos em matéria orgânica e propícios a formação de gás, margeado por sedimentos mais grossos e sem gás.
Phosphorites of the Brazilian continental margin, southwestern Atlantic ocean José Gustavo Natorf de Abreu, Iran Carlos Stalliviere Corrêa, Norberto Olmiro Horn Filho, Lauro Júlio Calliari Revista Brasileira De Geofisica, 2014 The existence of phosphate deposits in the Brazilian continental margin is known since the 1970’s and 1980’s after the Global Recognition of the Brazilian Continental Margin Program – REMAC Project (Programa de Reconhecimento Global da Margem Continental Brasileira – Projeto REMAC) a joint program to explorethe Brazilian continental margin. Phosphate deposits were collected on the seamounts offshore the northeastern Brazilian margin. In the early 2000’s, phosphate sampleswere taken incidentally by demersal fishing fleet in the southern Brazilian continental margin which contributed to the knowledge of these deposits in the southwestern Atlantic. This paper describes the mineralogy of the samples with scanning electron microscopy and X-ray diffraction. The new phosphate deposits in the Brazilian continental margin suggests a much wider phosphate distribution than imagined in the REMAC publications, thus representing a contribution to the effort of the Brazilian Government, through the Ministry of Mines and Energy, the Geological Survey of Brazil (CPRM), the Inter-ministerial Commission for the Resources of the Sea andthe Marine Geology and Geophysics Program who together undertake a Program to the Evaluation of the Mineral Potential of the Brazilian Legal Continental Shelf(REMPLAC), whose goal is to conduct a further investigation of the mineral potential of the Brazilian Territorial Sea and Exclusive Economic Zone (EEZ).Keywords: marine mineral resource, phosphate deposits, Rio Grande Terrace. RESUMO. A existência de depósitos fosfáticos na margem continental brasileira é conhecida desde as décadas de 1970 e 1980, graças ao Projeto de Reconhecimento Global da Margem Continental Brasileira (REMAC) quando fosforitas foram recolhidas sobre os montes submarinos da região Nordeste. No início dos anos 2000, amostras foram obtidas incidentalmente pela frota pesqueira demersal na margem continental sul brasileira, as quais foram incorporadas como novas ocorrências, contribuindo para o conhecimento destes depósitos no Atlântico sul ocidental. Este trabalho descreve a mineralogia deste material amostrado a partir de análises realizadas com microscópio eletrônico de varredura e difratometria de raios X. A localização das novas ocorrências de depósitos fosfáticos na margem continental brasileira sugere uma distribuição bem mais ampla desses recursos minerais marinhos do que se imaginava até as publicações do REMAC, representando, portanto, uma contribuição ao esforço do governo brasileiro, através do Ministério de Minas e Energia, do Serviço Geológico do Brasil, da Comissão Interministerial para os Recursos do Mar e do Programa de Geologia e Geofísica Marinha que, juntos, empreendemo Programa de Avaliação da Potencialidade Mineral da Plataforma Continental Jurídica Brasileira (REMPLAC), cujameta é realizar estudos mais aprofundados sobre a potencialidade mineral do Mar Territorial Brasileiro e da Zona Econômica Exclusiva (ZEE).Palavras-chave: recurso mineral marinho, depósitos fosfáticos, Terraço do Rio Grande.
Peat on the continental shelf of southern Brazil Comunicacoes Geologicas, 2014
Registro sedimentario del antiguo canal de desembocadura del Río de La Plata en la plataforma continental del sur de Brasil Revista Mexicana De Ciencias Geologicas, 2013
Climatic changes in the coastal plain of the Rio Grande do Sul state the Holocene: Palynomorph evidences Pan American Journal of Aquatic Sciences, 2010