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Disertaciones |
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1
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ADENILSON DA SILVA PEIXOTO JUNIOR
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Mata-catu failure system, recôncavo basin, bahia, brazil. A structural study and the importance of hazardous hazards in the nucleation of the system. New possibility
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Líder : LUIZ CESAR CORREA GOMES
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MIEMBROS DE LA BANCA :
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LUIZ CESAR CORREA GOMES
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CARLSON DE MATOS MAIA LEITE
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ARACY SOUSA SENRA
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Data: 17-feb-2020
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Resumen Espectáculo
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The Recôncavo Basin (BR) is located at southern portion of the rift system Recôncavo-Tucano-Jatobrá, specifically at the east side of Bahia. It shows NE-SW orientation and is structurally controlled by faults: (i) longitudinal N000-010, faults system (SF) of Maragogipe flexural border, and N030°-040° SF of Salvador edge and (ii) transversal N090°-100°, SF of Barra and N120°-N130° regarding to SF of transference. The Mata-Catu Fault System (SFMC), the main aim of this work, has an orientation of N150 ° -160 °, which is suggested to be a clearly structural discrepancy not easily explained mechanically by the models published of rift opening by E-W and NW-SE extensions. In addition, this system controls BR's significant hydrocarbon (HC) concentrations. Thus, this work sought to perform a detailed structural analysis of SFMC, in order to correlate under basin basement’s structures with those from the basin. For that, it was necessary to make a bibliographic review of the structures present in BR and its foundation, carry out field activities throughout the SFMC and analyze gravimetric and aeromagnetic anomaly maps. The result can be is explained according to two hypothesis for the structural inherence of the basement in the trend of the SFMC: (i) a swarm of mafic dikes from the Coastal Province of Bahia, dated 0.92 Ga and (ii) the suture zone between two tectonic blocks. Both possibilities could be crucial for understanding of this system. Especially regarding to fluid percolation and crustal thermal input which have fundamental importance for HC maturation.
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2
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PEDRO GONÇALVES DE NOVAES
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Ostracodes of the Tauá member, Candeias formation lower cretaceous of the Recôncavo Basin: taphonomy, paleobiogeography end paleoecology
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Líder : ALTAIR DE JESUS MACHADO
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MIEMBROS DE LA BANCA :
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ALTAIR DE JESUS MACHADO
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HELISANGELA ACRIS BORGES DE ARAUJO
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RICARDO PIAZZA MEIRELES
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Data: 28-feb-2020
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Resumen Espectáculo
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Based on the study of taxonomy and taphonomy of ostracod fossils as well as extensive bibliographic review, the characterization of paleobiogeographic and paleoenvironmental aspects of the Tauá Member, Candeias Formation, in the Recôncavo Basin, Bahia state, was carried out. The material used as a base for this study is a fossil content present in a paleontological collection that belongs to Petrobras. This content is from 25 selected wells, which were drilled by Petrobras and are distributed along the basin. Seven oyster taxa from the Local Andar Rio da Serra (Eocretaceous / Berriasian), which are from a biozone called Theriosynoecum varietuberatum varietuberatum (NRT-002), were identified: Cypridea ambigua, C. cf. Cypridea primaria, C. sellata, C. trinodosa, Reconcavona imitatrix, Theriosynoecum varietuberatum proximum and T. varietuberatum varietuberatum. They are typical of the subzone denominated C. cf. Cypridea primaria (NRT-002.2). The taphonomy was described based on aspects of ostracod valves, such as: (I) degree of fragmentation; (II) degree of disarticulation; (III) degree of dissolution; (IV) colouring and (V) occurrence of mineralization. It was observed that the majority of microfossils showed little or no fragmentation and disarticulation, in addition to the absence of dissolution, suggesting a low-energy paleoenvironment, with little transport and rework. Mineralizations were also registered, referring to the fossil diagenesis, mainly represented by pyritization and hematitization. The colours of the shells were compared with studies that associate them with the interpretation of the thermal history and maturation of organic matter. Moreover, ostracodes with dark colours may be related to the presence of oil in the rock in which they are present. In addition, a possible fauna zoning was observed between T. varietuberatum proximum and C. ambigua, based on the geographic distribution of the wells where they were found, possibly conditioned by tectonic-structural factors and / or physical-chemical factors. The lithological information and the fossils of exclusively non-marine individuals characterize the Tauá Member with continental sedimentation, typically lacustrine, generated under anoxic conditions. For this reason, the information obtained through this research can also contribute to the characterization of the evolution of the rift phase in the Recôncavo Basin.
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3
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DANIEL AUGUSTO DE MIRANDA
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A MINERAL SYSTEM APPROACH ON THE STRUCTURALLY-CONTROLLED AU-BEARING QUARTZ VEINS OF SERRA DE JACOBINA, SÃO FRANCISCO CRATON
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Líder : AROLDO MISI
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MIEMBROS DE LA BANCA :
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AROLDO MISI
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LUIZ CESAR CORREA GOMES
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CARLOS DINGUES MARQUES DE SÁ
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Data: 09-mar-2020
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Resumen Espectáculo
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The Serra de Jacobina is located northeast of Bahia state, Brazil. It consists of a 250-km-long, N-S mountain chain at the eastern border of the Gavião-Lençóis paleoplate and corresponds to the Contendas-Mirante-Jacobina Lineament northern portion. There are several structurally controlled Au-bearing quartz veins hosted by metasedimentary rocks of the siliciclastic Jacobina Group and Vale do Coxo metaultramafic rocks exploited by artisanal miners. Four of these occurrences, named Maravilha, Jaqueira, Morro da Palmeirinha and Mina Velha were mapped. They are hosted by two fault systems of Paleoproterozoic age, named from east to west, Pindobaçu and Maravilha. The Pindobaçu fault system is a transcrustal structure and represents the contact between the Gavião-Lençóis and Mairi paleoplates. The Maravilha fault system is a shallower structure limited to the upper crust. Mineralized veins are hosted by second order structures related to these two fault systems. The hydrothermal alteration varies according to the host rock. Disseminated sericitic alteration is widespread within Jacobina Group quartzites and conglomerates, probably replacing clay minerals. At Vale do Coxo schists, the alteration is pervasive, with chlorite replacing biotite, and of the fracture-filling fracture type as quartz veins. Sulfidation is subordinated to the sericitic alteration, both at quartzites and schists from the Jacobina Group and Vale do Coxo, respectively. Gold occurs like isolated crystals within quartz veins or subordinated to sericitic and/or sulfidation assemblages at host rocks. Petrography and fluid inclusion microthermometry revealed three main types, with subtypes, of fluids (density and salinity, expressed as g/cm³ and wt. % NaCl eq. respectively): (i) Type WC, two-phase H2O+CO2+NaCl fluid occurs at Maravilha (bulk density 0.7-1.0 , salinity 0.6-11.1) and Jaqueira (bulk density 0.8-1.0, salinity 2.0-14.2); (ii) Type W, two-phase H2O +NaCl or three-phase H2O +NaCl+solid fluid, subtypes We (density 0.6-0.9, salinity 0.8-17.9) and Wh (density 1.1-1.2, salinity 30.9-35.7) at Jaqueira, subtype Wmp (density 0.6-0.9, salinity 0.8-17.9) at Morro da Palmeirinha, vapor rich subtype Wmv (density 0.6-0.9, salinity 13.4-21.1) at Mina Velha, and subtype Wl (density 0.8-1.1, salinity 0.2-20.9) which occurs at Jaqueira, Morro da Palmeirinha and Mina Velha; (iii) Type C, dark color, one- or two-phase CO2-CH4 and/or N2 fluid (Tm CO2 -57.0 to -58.2°C, Th CO2 4.4 to 23.2°C) which occurs at Maravilha and Morro da Palmeirinha. At Jaqueira, combined microthermometric results with chlorite geothermometry, reveals that the hydrothermal alteration and gold deposition occurs with P-T conditions of 1.6-2.0 kbar and 303-346°C. The main mechanisms of gold deposition were fluid immiscibility and fluid-rock interaction. The hydrothermal mineralization at Serra de Jacobina is interpreted as an orogenic mineral system and the following elements were characterized: (1) The production of orogenic fluids with variable composition; (2) the fault systems in a compression-driven fluid flow type are conduits and driver; (3) the inductors of gold precipitation were fluid immiscibility and fluid-rock interaction.
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4
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TARSILA CARVALHO DE JESUS
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Intrinsec vulnerability to contamination of the Bambuí aquifer, western Bahia.
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Líder : LUIZ ROGERIO BASTOS LEAL
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MIEMBROS DE LA BANCA :
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LUIZ ROGERIO BASTOS LEAL
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RICARDO GALENO FRAGA DE ARAUJO PEREIRA
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HARALD RENE KLAMMLER
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Data: 16-mar-2020
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Resumen Espectáculo
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Karstic aquifers are naturally sensitive to contamination. Their intrinsic characteristics, which make them more vulnerable, demand the use of adapted methodologies for the vulnerability assessment of the peculiarities of the system. Among these characteristics we can mention: heterogeneity and anisotropy of the aquifers, shallow soils and direct recharge made through drains and other karst features. This theme has been increasingly applied worldwide and in Brazil the growth is also perceived. However, in the state of Bahia this cartography is still little worked out, especially in the karst aquifer that predominates in the west of the state, belonging to the Bambuí group. This work aimed at using two methods of assessing vulnerability to contamination, COP and PI, in the karst aquifer Bambuí, at the Corrente basin river. And also a simplified mapping for part of the Bamboo Group in Bahia. The resulting models were satisfactory and serve as a kick-off for karst vulnerability studies in the area. The results are presented in the form of two articles, which will be submitted to South America Earth Sciences and Environmental Earth Sciences respectively.
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5
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DANIELA LEAL RODRIGUES
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GEOTERMOBAROMETRY OF SAFIRINE AND GARNET-ORTHOPYROXENE BEARING GRANULITES FROM PACIÊNCIA BEACH, SALVADOR, BAHIA
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Líder : JAILMA SANTOS DE SOUZA DE OLIVEIRA
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MIEMBROS DE LA BANCA :
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JAILMA SANTOS DE SOUZA DE OLIVEIRA
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ANGELA BEATRIZ DE MENEZES LEAL
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CARLSON DE MATOS MAIA LEITE
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Data: 13-abr-2020
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Resumen Espectáculo
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The outcrop of the Paciência’s beach, in Salvador city, is located in the geotectonic setting of the São Francisco’s Craton, more specifically in the extreme south of the Salvador-Esplanada-Boquim Belt (CSEB). In this work, a study was realized in two of the metamorphic lithotypes present in the outcrop: garnet - orthopyroxene granulites and sapphirine granulites. The first consists of garnet and orthopyroxene porphyroblasts surrounded by a matrix formed by plagioclase + biotite ± K-feldspar ± quartz ± chlorite, in addition to zircon, apatite and sericite as traces. Simplectites between orthopyroxene + spinel + cordierite ± garnet occur at the rims of porphyroblasts or dispersed in the matrix. The sapphirine granulites are presented under three lithofacies: now formed by garnet porphyroblasts containing inclusions of sillimanite, sapphirine, mesoperthite and quartz, bordered by simplectites between orthopyroxene + spinel + cordierite and matrix formed by plagioclase + biotite ± K-feldspar ± quartz ± chlorite ± myrmekite; sometimes as simplectites between orthopyroxene + sapphirine + spinel + cordierite surrounded by a matrix of biotite + plagioclase + cordierite ± K-feldspar ± quartz ± chlorite; or as simplectites between orthopyroxene + sapphirine, where garnet can occur included in sapphirine and spinel in the center of the simplectites, this arrangement being surrounded by a matrix of biotite ± chlorite. Zircon, apatite and opaque can occur as traces in the three lithofacies. Mineral chemistry studies have indicated that, in garnet - orthopyroxene granulites, garnet is a solid solution dominated by the almandine - pyrope pair, with molar% content ranging between alm52-55 and prp40-43 in the core, and alm55-60 and prp28- 39 at the rims. XMg in garnet ranged from 0.45 to 0.37 and 0.64 - 0.69 in orthopyroxene. Al content in orthopyroxene ranged between 0.43 and 0.30 apfu in porphyroblasts, with values decreasing from the core towards the rims, while in simplectites between 0.35 and 0.26 apfu. Plagioclase porphyroblasts shows values of An43-19, and for the grains of the matrix between An40-31. In the sapphirine granulites, the garnet had contents of alm48-51 and prp44-45. XMg in garnet ranged between 0.46 - 0.48, in orthopyroxene 0.74 - 0.77 and sapphirine 0.82 - 0.87. Al content for orthopyroxene varied between 0.27 - 0.40 apfu. Thermobarometric studies on garnet - orthopyroxene granulites resulted in conditions of metamorphic peak of P ~ 1.04 GPa and T ~ 1016 °C, associated in this work with the Dn deformation phase of Salvador. It is suggested that the following steps of decompression and cooling Dn + 1, yielding the simplectites and reequilibrated the matrix, furthering the consumption of mineral phases by biotite ± chlorite during the late cooling phase. For this late phase, the calculated T break resulted in 616.5 - 770.7 ° C, by orthopyroxene - sapphirine thermometry. It is believed that the diffusion between Fe-Mg acted intensely during the late cooling stage in the safirina granulites sample, so that the results obtained for the pseudoseections showed up to be unreliable. However, reaction microstructures and petrogenetic grid suggest that these lithotypes crossed the P-T paths after a metamorphic peak of near-isothermal decompression.
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6
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CARLOS GLEIDSON CAMPOS DA PURIFICAÇÃO
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ANALYSIS OF MULTICRITERY DECISION AND GIS APPLIED TO THE MANAGEMENT OF URBAN SOLID WASTE IN CHOOSING AREAS FOR IMPLEMENTING SANITARY LANDFILLS
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Líder : LUIZ ROGERIO BASTOS LEAL
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MIEMBROS DE LA BANCA :
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LUIZ ROGERIO BASTOS LEAL
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DANILO HEITOR CAIRES TINOCO BISNETO MELO
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PATRICIA LUSTOSA BRITO
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JOÃO DA SILVA FORTUNA NETO
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Data: 02-oct-2020
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Resumen Espectáculo
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The environmentally appropriate destination for solid urban waste is recycling and / or composting and, when all possibilities of using this waste are exhausted, the incineration and / or disposal of waste in landfills. However, about 40% of the world's waste is disposed of inappropriately in controlled dumps and /or landfills. The environmentally appropriate way of disposing of this waste is landfills. This study aimed to identify areas for landfill implementation in the Metropolitan Region of Salvador, with the help of the geographic information system, and the analysis of multicriteria decision. Two preliminary models were generated: the first used restrictive criteria established by Brazilian legislation applied to fifteen factors / themes; in the second, non-restrictive criteria applied to eleven factors / themes were used, based on technical knowledge and literature, defining weights using the AHP method. The first model showed 30% of suitable areas and 70% of unsuitable areas. The second model presented 8.4% of very favorable areas; 32.4% favorable; and 59.2% were not favorable. Finally, the final model, resulting from the crossing of the two models, where 6.05% of the total areas were classified as very favorable; 15.95% favorable; 8.56% not favorable; and 69.44% inapt areas. Although the proposed method is applicable in any geographic region, it is necessary to understand its limitations and / or modifications, since the factors and criteria used are inherent to the areas studied and it is only possible to establish strict rules for restrictive criteria when there are specific laws. In the case of non-restrictive criteria, the analysis is subjective, with the specialists being responsible for determining the decisions.
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7
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ALDENEIDIANE SANTANA DOS SANTOS
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Evolucion the contaminesion of the soil for toxic metal
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Líder : JOSE ANGELO SEBASTIAO ARAUJO DOS ANJOS
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MIEMBROS DE LA BANCA :
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JOSE ANGELO SEBASTIAO ARAUJO DOS ANJOS
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MANOEL JERONIMO MOREIRA CRUZ
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MARIA ELOISA CARDOSO DA ROSA
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Data: 13-nov-2020
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Resumen Espectáculo
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Contamination by toxic metals present in the soil of the municipality of Santo Amaro, Bahia, Brazil is a topic widely discussed by the scientific community and local news, especially in recent years. The evolution of research on the subject began in 1980, with the environmental monitoring carried out by Tavares (1990), in an attempt to expose the scenario of lead and cadmium contamination in soils and in a group of residents considered to be at high risk (women and children) ) and, through this, proved that the level of these metals in samples of soil and human material were above the limit proposed by law. To assess the quality of a contaminated soil, specific criteria and guidelines are necessary, respecting the heterogeneity of this resource. The use of guiding values from other countries can cause geochemical interpretations not consistent with the local reality. The National Environment Council brought, through resolution 420/2009, the appropriate methodology for assessing soil quality, regarding the presence of chemicals of anthropic origin and must be carried out based on Guiding Values of Quality Reference, of Prevention and Research. The study area is located in the former facilities of Plumbum Mineração e Metalurgia. The objective of this research is to evaluate a series of published works, a total of 20 (twenty), which were carried out on surface soils during the period from 1980 to 2019 in the municipality of Santo Amaro, considering that the existence of toxic metals in the soil are serious risks to public health and the environment. The applied methodology is restricted to Bibliographic Research and was divided into 4 (four) distinct phases, having as main indicators the period of publication and the fact that it marked a new phase in the research on the contamination of these soils. Finally, geostatistics is applied to analytical data for toxic elements (Pb, Cd, Zn, Cu, As and Ag) from the Plumbum Mineração e Metalurgia website provided by the CPRM-RJ and IGEO-UFBA partnership. The concentrations reveal average, minimum and maximum values for lead (Pb) 2,611.4, 179.5 and 12,500 mg / Kg; cadmium (Cd) 43.9, 4 and 230mg / Kg; zinc (Zn) 440, 81 and 2,399mg / Kg; copper (Cu) 115.6, 20 and 716mg / Kg; arsenic (As) 18.3, 2 and 118mg / Kg and silver (Ag) 2.8, 0.1 and 11mg / Kg, respectively. The research shows that, over the years, especially after 2009, the background values for the Santo Amaro region have not yet been defined by environmental entities, which reflects the non-compliance with the legislation. The case of Santo Amaro contamination requires the definition of these values in order to build legislation aimed at monitoring these elements in the region's soils. The study by Santos et al. 2017 is the first step, following the specifications of regulation 420/2009, but without recognition by the competent bodies of the State. The monitoring program initiative proposed by CPRM in partnership with IGEO-UFBA, for the next 20 years in the region, aims to obtain results that contribute to the improvement of environmental quality and, consequently, a higher quality of life for the population of Santo Amaro.
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8
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HERNAN SALES BARREIRO
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AUTOMATIC EXTRACTION OF LINEAMENTS IN GROUNDWATER EXPLORATION: A CASE STUDY OF METASEDIMENTARY AQUIFERS OF THE CENTRAL-NORTHERN CHAPADA DIAMANTINA
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Líder : NATANAEL DA SILVA BARBOSA
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MIEMBROS DE LA BANCA :
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NATANAEL DA SILVA BARBOSA
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CRISTOVALDO BISPO DOS SANTOS
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PABLO SANTANA SANTOS
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Data: 25-nov-2020
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Resumen Espectáculo
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In today's globalized world, the study of groundwater is increasingly important as an instrument capable of providing a solution to water problems associated with the continuity of human activities. In this sense, groundwater exploration and assessment techniques are always under development, aiming to increase assertiveness in the location of tubular wells and the subsequent increase in exploited flows. Therefore, this work aims to evaluate the techniques of automatic extraction of structural lines and the possibilities of application in hydrogeological prospecting. The development of this work was based on a bibliographic survey in various sources. The techniques of automatic extraction of lineaments consist of the identification and vectorization of linear features in remote sensing products (i.e., satellite images, geophysical data, etc.) pre-processed. Processing takes place using algorithms, through edge detection, thresholding and curve extraction. The resulting lineaments can be used in the characterization and prospecting of fissural aquifers. Therefore, it is possible to perform a quantitative and qualitative analysis of the extracted lines and the possible relationships with hydrogeological parameters (i.e., flow, specific capacity, etc.). It is also possible to perform a multicriteria analysis in a GIS environment between the lineaments and other factors (i.e., lithology, drainage, geomorphology, relief, etc.) always aiming at the identification of areas suitable for the location of tubular wells. Finally, it is concluded that the use of automatic extraction of lineaments in hydrogeological prospecting has great potential for improving productivity in the location of tubular wells, especially in the northeastern semiarid, where fissural aquifers predominate.
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9
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JÉSSICA BRUNHILDE LIRA RIOS
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TAXONOMY OF OSTRACODES AND PALAEOENVIRONMENTAL OF ITAPARICA FORMATION (LOWER CRETACEOUS), IN RECÔNCAVO BASIN, BAHIA, BRAZIL
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Líder : RICARDO PIAZZA MEIRELES
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MIEMBROS DE LA BANCA :
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ENELISE KATIA PIOVESAN
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RICARDO PIAZZA MEIRELES
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SIMONE SOUZA DE MORAES
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Data: 04-dic-2020
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Resumen Espectáculo
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Ostracods are present in all aquatic environments, in a large scale of time and space, from shallow lakes to abyssal areas. Geographically and temporally present, with a carbonate carapace structure resistant to fossilization processes and the existence of many post-Paleozoic families today, ostracods are important bioindicators. The lower Cretaceous (Berriasian/ Rio da Serra Stage), marked by more intense tectonism and humid climate, favored the installation of lakes with small river incursions such as Lake Itaparica (Itaparica Formation), replaced by a fluvial-aeolian system (Formation Grande Water). The studies and scientific publications of Itaparica Formation’s bioestratigraphy are rare, making it difficult to deepen the characterization of the formation as well as its evolution. The study of the ostracods of the Itaparica Formation of the Recôncavo Basin allowed the identification of four genera and seven different species of ostercods: Kegelina kegeli, Kegelina bisculpturata, Kegelina armata, Kegelina depressa; Praecypridea acuta, Cypridea brevicornis, Theriosynoecum fittoni, included in the biozone RT-002.2 of the Rio da Serra Stage. Five of these species have been updated to their most recent reclassifications in relation to their original publications, from the genus Cypridea to Kegelina and Cypridea to Praecypridea. The species of Theriosynoecum present in the formation, previously understood as two distinct species, are understood in this work, as a variation of its ornamentation in the carapace of Theriosynoecum fittoni. According to the lithological analysis of the drilling profiles, the Itaparica formation is composed of siltstones, shales, sandstones and carbonates interspersed in a varied way throughout the entire basin, presenting a greater siliciclastic contribution in the northeast region of the basin interpreted as by river input. The present project has a partnership with the company Petróleo Brasileiro S.A. - Petrobras, via ANP (National Petroleum Agency), providing technical support materials, availability of physical space and participation of the project co-supervisor, mediator of the development of the study.
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10
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JOÃO PEDRO MORENO GOMES
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Coastal Province mafic Dykes, State of Bahia: Comparative study with Ilhéus-Olivença
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Líder : ANGELA BEATRIZ DE MENEZES LEAL
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MIEMBROS DE LA BANCA :
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ANA CAROLINA PINHEIRO AMORIM
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ANGELA BEATRIZ DE MENEZES LEAL
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JAILMA SANTOS DE SOUZA DE OLIVEIRA
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Data: 07-dic-2020
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Resumen Espectáculo
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Comparative studies of petrographic, geochemical and geochronological data of mafic dykes allow establishing relationships among different swarms, their processes of genesis and magmatic evolution, contributing to the geodynamic evolution of a given region and the characterization of the nature of mantle sources of extensional events. The mafic dikes of Ilhéus-Olivença, Salvador, Camacan and Itajú do Colônia, belonging to the Coastal Province (PL), are located in the northeast of the Francisco Cráton, close to the sea coast of Bahia and emplaced in granulitic rocks of paleoproterozoic orogenic belts. The Ilhéus-Olivença swarm has dikes with average thickness of less than 3 m, with preferential E-W orientation and host rotated enclave structures, with magmatic flow directed from east to west. The essential mineralogical assembly is composed of plagioclase, pyroxenes, olivine, hornblende and opaque minerals, presenting intergranular, ophitic, porphyritic and subophitic textures, besides secondary alteration processes. They are tholeiitic basalts of intra-plate setting, with slight enrichment in ETRL compared to ETRP, showing an E-MORB source, with samples close to the primitive mantle. When compared with the other mafic dykes of PL, they have similarities in terms of field, petrographic and geochemical aspects. The integration of geochemical studies with geochronological data from the PL literature reveals that these rocks are part of the same extensional Tonian event, probably related to the same mantle plume.
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Tesis |
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1
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JAILSON JUNIOR ALVES SANTOS
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Petrogenesis of the Alkaline Floresta Azual Complex, South Bahia State
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Líder : HERBET CONCEICAO
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MIEMBROS DE LA BANCA :
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ANTÔNIO CARLOS GALINDO
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CARLOS DINGUES MARQUES DE SÁ
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CLAUDIO NERY LAMARÃO
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DEBORA CORREIA RIOS
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HERBET CONCEICAO
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IGNEZ PINTO GUIMARÃES
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MOACYR MOURA MARINHO
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Data: 08-may-2020
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Resumen Espectáculo
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The Floresta Azul Alkaline Complex represents one of the batholiths of the South Bahia Alkaline Province. This complex has an area of 200 km , located in the northern part of this alkaline province and is intrusive in the granulite terrains of the Itabuna-Salvador-Curaçá Orogen. It consists of two contemporaneous, but distinct, intrusions that have contact by fault: a syienitic localized on the west side of the batholith and a monzonitic intrusion on the east. A syenitic intrusion is formed by nepheline syenites miaskitics that were submitted to an autometasomatic process at the end of the magmatic evolution by different fluids (Cl, CO3, S). The textual and mineralochemical studies of the nepheline syenite identified a complex crystallization sequence that involves the magmatic stage (baddeleyite, zircon, pyrochlore, allanite, magnetite, ilmenite, apatite, aegirine-augite, hornblende, siderophyllite, albite, perthitic k-feldspar, nepheline and sodalite), autometasomatic (zircon-2, pyrochlore-2, apatite- 2, sodalite-2, cancrinite, calcite, pyrite, sphalerite and carbocernite) and hydrothermal (magnetite-2, ilmenite-2, titanite, monazite, ancylite, hydroxyfluorides, siderite, ankerite, stroncionite). The monazite presents in the rocks of the complex is formed by different processes and associated with apatite: in syenites by recrystallization, in monzonites by leaching and in phenites by exsolution. The textures in calcite crystals were the key to identify the stages: autometasomatic (calcite exsolve carbocernite) and hydrothermal (calcite recrystallized in ancylite and form siderite, ankerite and strontianite). Monzonitic intrusion presents an important volume of monzonitic and dioritic microgranular mafic enclaves. The field relations (sin-plutonic dykes, like pillow structures, shapes and contacts of the enclaves), textural (acicular apatite, mineral zonations) and geochemical (linear evolutions), indicate the existence of a mixture between cogenetic mafic and felsic magmas in the formation of monzonitic intrusion. The rocks (monzonites and enclaves) have medium alkalinity, they are metaluminous and the elements outlined that these magmas are anorogenic with OIB type signature correlated a continental rift.
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2
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DANILO SILVA LISBOA
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Probabilistic forecast of coral bleaching: theoretical and proactical aspects for the development of an early alert system to reefs of the Atlantic Ocean
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Líder : RUY KENJI PAPA DE KIKUCHI
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MIEMBROS DE LA BANCA :
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ESTEVAM RAFAEL HRUSCHKA JUNIOR
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MARILIA DE DIRCEU MACHADO DE OLIVEIRA
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RICARDO ARAUJO RIOS
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RUY KENJI PAPA DE KIKUCHI
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ZELINDA MARGARIDA DE ANDRADE NERY LEAO
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Data: 14-sep-2020
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Resumen Espectáculo
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Coral bleaching represents the most prominent negative response of reef ecosystems to current climate change. Capable of promoting mass mortality of colonies and significant changes in reef community structures, these phenomena should become increasingly frequent, intense, long-lasting and globally widespread, to the point of compromising the viability of reef ecosystems in the coming decades. The choice of Bayesian nets for bleaching modelling comes from their inherent ability to integrate data and knowledge with different characteristics and to deal with the uncertainties and complexities related to these phenomena through the use of probabilities. In this research reasons why the Bayesian approach can be quite proficient for modelling reef environments and particularly for the case of coral bleaching are presented, and the most relevant aspects of key references are discussed in more detail from the perspective of the reef scientist/modeler. We describe the nature and procedures for building these models, providing recommendations for appropriate modeling in each of the major steps. We present a case study of formalizing the conceptual model of seasonal coral bleaching prediction from a control case in an environmental reserve area. For this, two well founded scientific ideas have been evaluated and confirmed in relation to their forcefulness in bleaching events: 1- there is a relationship between the intensity of the El Niño phenomenon and positive thermal anomalies in the Atlantic Ocean; and 2- the bleaching of corals is mainly influenced by positive thermal anomalies in seawater. The formalised conceptual model has hyeraquically organised the indicators related to these assumptions into a network structure according to their levels of influence on bleaching and has been used as a starting point to develop competing models capable of making seasonal forecasts for the reef areas of the North Atlantic Ocean. Data mining procedures, validation, and scoring tests were used as criteria for comparison, demonstrating the feasibility of the Bayesian approach to make seasonal forecasts of the bleaching state with accuracy levels above 80%. As alternatives to improve accuracy, customized models were developed with databases restricted to specific situations, but at the cost of loss of predictive capacity. We believe that the Bayesian network model developed, tested and evaluated in this research represents a useful resource to assist scientists, governments and environmental managers through a bleaching early warning system capable of providing sufficient time to plan field campaigns and possible mitigation actions. Finally, from the point of view shown in this research, the Bayesian approach represents an alternative with expressive potential to assist the management of reef ecosystems and should be established as a standard technique of analysis in the coming years. Familiarizing oneself with the characteristics and procedures of this approach should be of great value to students/researchers and managers committed to safeguarding the future viability of these priceless ecosystems.
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3
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LEANIZE TEIXEIRA OLIVEIRA
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TRANSITIONAL WATER BALANCE AND ANALYSIS OF WATER LEVEL VARIATIONS IN SOUTHERN PORTION OF THE URUCUIA AQUIFER - BAHIA
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Líder : LUIZ ROGERIO BASTOS LEAL
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MIEMBROS DE LA BANCA :
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JOANA ANGELICA GUIMARAES DA LUZ
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José Geilson Alves Demétrio
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LUIZ ROGERIO BASTOS LEAL
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MARIA DO ROSARIO ZUCCHI
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MARIO JORGE DE SOUZA GONÇALVES
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Data: 05-oct-2020
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Resumen Espectáculo
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The west of the state of Bahia-Brazil, the largest agribusiness area in the state, is experiencing a progressive occupation since the 1980s, causing pressure on water resources, mainly after the introduction of irrigation, and already presenting conflicts between water users. The water resource has been the driving force behind agricultural activities, and given its strategic importance and the hydraulic coupling between rivers and aquifers, hydrological studies need analyzes that integrate the dynamics of surface and groundwater. This research presents a spatial and temporal analysis of the components of the water balance in order to understand the dynamics of the main water flows in the Arrojado, Formoso and Éguas watershed, tributaries of the Corrente river basin in Bahia, and their reflections in the groundwater levels of the Urucuia aquifer. The effects of the extraction of groundwater by wells in a portion of the Urucuia Aquifer System and the quantification of the components of the water balance were made using the simulation of groundwater flow in a stationary regime for three scenarios: i) without pumping; ii) with current pumping and; iii) with 60% more extraction by wells. After defining the production flows of the current wells (4.6 m3 s-1) and modeling the geometry of the aquifer base (maximum thickness of 535 m), the stationary models without pumping and with pumping show that, in long term, groundwater storage decreases by 2 km3 (average drop in the 0.8 m aquifer) without interference in the direction of regional flow. The mass balance shows that the base flow of the main rivers is reduced by approximately 6% after the current groundwater extraction and a further 2.5% after the increased extraction. Isotopic analysis was also used in conjunction with the numerical simulation of transient flow to describe the dynamics of the components of the water balance between 2005 and 2018. The isotopic analysis highlights the river-aquifer interaction, the effect of evapotranspiration on the recharge and the amount effect. The results show a progressive decrease in recharge between 2012 and 2017, the importance of EVPT in recharge calculations, and a decrease in rainfall, causing a decline in groundwater levels and the base flow of rivers (average river flows also come declining, reflecting joint actions to decrease base flow and direct withdrawal of water for irrigation), and suggests that effective recharges occur in high volume rains. The simulation also predicts that in the event of a 10% decrease in recharge, hydraulic loads and base flows take approximately a decade to rebalance. Considering that the exploitation of aquifers must be guided by the environmental sustainability of the water system in order to balance the pumping conditions and the mitigation of their consequences, the importance of continuous hydroclimatological monitoring and measurement of withdrawals becomes evident, aiming to follow the dynamics between demands and water availability. The results point to a greater impact of the exploitation of aquifers on rivers, caused by a reduction in storage and base flow.
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4
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MAISA BASTOS ABRAM
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EARLY AND MIDDLE DEVONIAN PHOSPHOGENESIS IN NORTHERN GONDWANA (PARNAÍBA BASIN, BRAZIL): PETROGRAPHIC, GEOCHEMICAL AND ISOTOPIC EVIDENCE FOR PHOSPHORUS CYCLING
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Líder : MICHAEL HOLZ
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MIEMBROS DE LA BANCA :
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AROLDO MISI
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CLEIDE REGINA MOURA DA SILVA
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JOSE MARIA LANDIM DOMINGUEZ
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MICHAEL HOLZ
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SERGIO BERGAMASCHI
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Data: 27-oct-2020
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Resumen Espectáculo
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The Devonian is a period of climate change and epeiric seas, with phosphate successions, but with little economic importance, such as the northwestern areas of Gondwana margin in Brazil. The objective of this work is to deepen the knowledge about the occurrences of Devonian phosphates, in order to approach this theme, with the establishment of phosphogenetic models and implications on the evolution of the planet and mineral potential. Pragian to Givetian successions in the Canindé group, Itaim and Pimenteira formations, Parnaíba Basin (Brazil) were investigated. Phosphorite and phosphatic ironstone rich successions and their host rocks were investigated in an integrated study based on sedimentology, high resolution sequence stratigraphy with petrographical, mineralogical and geochemical (whole rock major and trace element, δ13C and δ18O isotope, total organic carbon/total sulfur and Corg/P ratio) data to highlight paleoproductivity, redox, recycling, diagenesis and phosphogenetic processes. Lithofacies stacking patterns indicate that deposition occurred during marine transgressions resulting in four depositional sequences (B, C, D and E) and 19 parasequences. Phosphorite occurs is in the form of concretions or pristine layers in offshore environment, near SWB (outer/inner shelf) precipitated under suboxic to anoxic conditions. It also occurs as glauconite francolite nodules in hetherolitic lithofacies precipitated in oxic to suboxic zones. Ironstone and phosphatic ironstone were deposited in more proximal settings, near FWWB. Molibdenium, V/Cr and V/(V+Ni) ratios for phosphatic ironstone and ironstone intervals indicated variations from dysoxic/suboxic conditions to more anoxic and minimal dissolved H2S in phosphatic ironstone intervals. Total sulfur versus TOC indicated variations from dysoxic, anoxic and even euxinic conditions for organic lithofacies. Distinctive MREE enriched patterns are similar to other Devonian phosphorites patterns, even for samples with authigenic francolite precipitation near surface water. The variation for the siderites was of δ18O (VPDB) -12.0 to 2.5 and δ13C-21.5 to -0.8. The variation indicates early diagenesis with pore-water sensitive to organic degradation that evoluted from sulfate reduction to iron reduction zones and possible variations in salinity due to mixing freshwater. Francolite presented more clustered data points then siderites (δ18O VPDB from -14.11‰ to -4.6‰) / (δ13C from -2.9‰ to -8.1‰), although δ18O VPDB data were strongly affected by weathering. We recorded that the limit inner/outer shelf waters were more enriched in P concentrations then shorewards regions, with the development of phosphogenesis along the shelf generating an oxygen minimum zone with geochemical data like modern upwelling sites. River discharges probably affected physical characteristics of the upper water column and produced large spatial variability in the Parnaiba basin system probably influencing vertical stratification and salinity or temperature leading to gradients of surface nutrient concentrations. Not only upwelling ferruginous water but terrestrial contribution of OM contributed to enhance shallower anoxia resulting in reduced total phosphorus burial efficiencies. The phosphorus cycle was probably affected by the global low oxygen and anoxic conditions in the Devonian. This may have affected the burial of P across the entire shelf, implicating in low economic potential for Early and Middle Devonian phosphorites, although rare earth elements and yttrium concentrations represent a potentially economic byproduct.
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5
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ROGÉRIO DE JESUS PORCIÚNCULA
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HYDROGEOPHYSICS AND URBAN SOLID WASTE: STUDIES OF CASES IN SANITARY LANDFILLS IN THE SOUTHERN AQUÍFERO SYSTEM SÃO SEBASTIÃO, RMS / BA
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Líder : LUIZ ROGERIO BASTOS LEAL
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MIEMBROS DE LA BANCA :
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CRISTOVALDO BISPO DOS SANTOS
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LUIZ ROGERIO BASTOS LEAL
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SUSANA SILVA CAVALCANTI
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Thomas Vincent Gloaguen
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VANIA EUNICE BAHIA
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Data: 02-dic-2020
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Resumen Espectáculo
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The present work, entitled “Hydrogeophysics and solid urban waste: case studies in landfills in the southern portion of the São Sebastião aquifer system, RMS / BA” presents the results of the doctoral research of student Rogério de Jesus Porciúncula, in compliance with the requirements of the Pos-graduate Program in Geology, Federal University of Bahia, under the academic guidance of Professor Dr. Luiz Rogério Bastos Leal. There were two scientific articles published in Brazilian Journal of Geophysics: (i) the first, entitled “Geoelectric characterization for landfill implantation, in Simões Filho, Bahia, Brazil”, was made up of twelve vertical electrical soundings, two SPT soundings and one geological sounding composed the quantitative surveys and techniques used. Unidimensional inversions presented mean error of 4.1%. Bidimensional inversions presented 5.7% mean error. Lower-value geoelectrical facies were attributed to occurrences between the silt and clay fraction, while higher-value facies corresponded to occurrence between the silt and sand fraction. The hydrostratigraphic model included a confined aquifer, represented by a succession of alternating sandy and clayrich layers with subhorizontal contact. Moreover, water occurred in permeable porous layers, between depths of 40 and 50 m, approximately. Regarding the degree of compactness, soils were classified as medium to hard; and (ii) the second article, entitled “Hydrogeophysical characterization of the Marizal - São Sebastião aquifer system in the surrounding of the LIMPEC sanitary landfill, municipality of Camaçari, Bahia, Brazil”, revealed the occurrence of a conductivity anomaly, possibly attributed to the contamination plume, dispersed within the saturated zone, and presenting a SSE convection direction. The one-dimensional inversions allowed to interpret the stratigraphic model. The two-dimensional inversions produced inverted geoelectrical profiles, with a mean error below 2%, and confirmed the occurrence of possible contamination plumes disseminated within the unsaturated zone and dispersed within the saturated zone. The geoelectrical facies with the highest resistivity values were related to the São Sebastião Formation, with intermediate values to the Marizal Formation, and the lowest values to contamination plumes and/or eventual occurrences of silt/clay. The porosity, hydraulic conductivity and transmissivity parameters were estimated to be between 19.2 to 34.2%, 0.11 to 3.37 x10-3 cm /s and 4.7 to 145.6 m² / d, respectively; and the vulnerability of the local free aquifer was classified as high.
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6
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MARCUS VINÍCIUS COSTA ALMEIDA JÚNIOR
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PETROGRAPHY, LITHOCHEMISTRY AND GEOCHRONOLOGY FROM GNAISSIC-MIGMATITIC COMPLEX OF THE SALVADOR-ESPLANADA-BOQUIM BELT
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Líder : ANGELA BEATRIZ DE MENEZES LEAL
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MIEMBROS DE LA BANCA :
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ANGELA BEATRIZ DE MENEZES LEAL
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JAILMA SANTOS DE SOUZA DE OLIVEIRA
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NATALI DA SILVA BARBOSA
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CRISTINE LENZ
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ERON PIRES MACEDO
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Data: 04-dic-2020
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Resumen Espectáculo
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The Salvador-Esplanada-Boquim Belt (CSEB) is located in the northeastern portion of the São Francisco Craton, in the states of Bahia and Sergipe, presenting two lithological strips of metamorphic rocks, called Gnáissico-Migmatítico Complex (CGM) and Esplanada-Boquim Granulitic Complex. The present work was restricted to CGM field, petrographic, lithochemical and geochronological studies. Macroscopically, this complex is highly migmatized, with a predominance of the process in its western portion. The petrographic study allowed to classify the rocks as granitic to granodioritic and, subordinately, tonalitic. The rocks were lithochemically divided into sodium, potassium and intermediates, due to their alkalinity, being characterized as peraluminous to metaluminous. Analyzes of trace elements, rare earths and Eu / Eu * ratios allowed to interpret the occurrence of metasomatic processes, based on crustal fusion of a calcium-alkaline nature. Eight U-Pb geochronological analyzes (LA-ICP-MS) were carried out on zircons of the CGM rocks, six of which were embedded and two of granitic dykes. The obtained data allowed to conclude that the CGM rocks were formed between 2150 ± 19 - 2188 ± 30 Ma, while the dykes had their crystallization concomitant to the regional metamorphism process, in approximately 2073 Ma. These metamorphic events are interpreted as products of the collision with the Serrinha Block, generating deformation, compression and uplift of these rocks, configuring the zones of regional shear and shear failures, present in this belt. Subsequently eroded, the granulitic roots of the CSEB were exhumed, stabilizing as it currently stands, with the CGM rocks, located to the east and west of the Esplanada-Boquim Granulitic Complex.
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7
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MARIA CLARA MARTINS CARDOSO DUARTE
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GRANITOGENESIS ASSOCIATED WITH BRUMADO-BAHIA GRANITE-GREENSTONE, GAVIÃO BLOCK, SÃO FRANCISCO CRATON: PETROGENETIC CONSIDERATIONS
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Líder : ANGELA BEATRIZ DE MENEZES LEAL
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MIEMBROS DE LA BANCA :
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AMALVINA COSTA BARBOSA
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ANGELA BEATRIZ DE MENEZES LEAL
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ERON PIRES MACEDO
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JAILMA SANTOS DE SOUZA DE OLIVEIRA
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MARIA ZÉLIA AGUIAR DE SOUZA
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Data: 15-dic-2020
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Resumen Espectáculo
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The granite-greenstone terrains of the Brumado region are inserted in the geotectonic macrounity of the São Francisco Craton, more specifically in the southern portion of the Gavião block, and represent the primitive substrate of the region, with Archaean age. Nine different lithotypes were identified: the Brumado Greenstone-belt, Gavião orthogneiss, monzogranitic orthogneiss, Caraguataí orthogneiss, metassienogranite, metagranodiorite, leucogranite, Serra da Franga granite and porphyritic metassienogranite. The objective of the present work was to carry out petrographic and geochemical studies (especially the ETRs standards) of granitogenesis and basement in the Brumado region, in addition to geochronological analyzes focusing on granitogenesis. It was possible to suggest that the metasienogranite is the result of partial fusion of monzogranitic orthogneiss (because it presents partial fusion relationships, same ETR pattern and same geochemical behavior of major elements and trace) and, leukogranite is a result of partial fusion of Gavião orthogneiss ( TTG Archean), when also analyzing this comparison of the behavior of the major elements and trace, in addition to the ETR standard. Both Serra da Franga granitoids, porphyritic metassienogranites and metagranodiorites are possibly intrusive granitoids in the final stages of formation of these lands. The study of the tectonic ambience of these lithotypes corroborated the results obtained through the analysis of the major elements, trace and ETRs, and revealed an intraplate origin for the syenogranite and the monzogranitic orthogneisses. The Gavião orthogneiss, together with leucogranite, revealed the same origin, that of a magmatic arc. Serra da Franga granitoid, metagranodiorite and porphyritic metassienogranite also have a magmatic arc origin, related to late intrusions common in these types of terrain. U-Pb analyzes were performed on zircon (LA-ICP-MS), on three intrusive granitoids in the BG: porphyritic metassienogranite, metagranodiorite and Serra da Franga granite from the region. The porphyritic metasienogranite showed a protolite crystallization age of 3216 ± 48 Ma indicating paleoarquean magmatism. The metagranodiorite revealed a crystallization age of 2697 ± 12 Ma, registering neoarquean magmatism, thus demonstrating the importance of a magmatic event of this age, since neoarquean granitoids occur in a small proportion in the state of Bahia. The Serra da Franga granitoid revealed an age of 2107 ± 27 Ma, corroborating with Riacian magmatism, in accordance with other intrusive bodies in the southern BG of similar ages. The obtained ages suggest the existence of paleoarquean and neoarquean magmatism in this sector of the Gavião block, in addition to intrusive paloproterozoic granitoids in this region.
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