FCT - Artigos publicados em periodicos

URI Permanente para esta coleção

http://200.137.215.59//handle/ri/11335

Navegar

Agora exibindo 1 - 13 de 13

Recycling process and proto-kimberlite melt metasomatism in the lithosphere-asthenosphere boundary beneath the Amazonian Craton recorded by garnet xenocrysts and mantle xenoliths from the Carolina kimberlite
(2022) Gervasoni, Fernanda; Jalowitzki, Tiago; Rocha, Marcelo Peres; Weska, Ricardo Kalikowski; Novais-Rodrigues, Eduardo; Rodrigues, Rodrigo Antonio de Freitas; Bussweiler, Yannick; Barbosa, Elisa Soares Rocha; Berndt, Jasper; Dantas, Elton Luiz; Souza, Valmir da Silva; Klemme, Stephan
Here we present new data on the major and trace element compositions of silicate and oxide minerals from mantle xenoliths brought to the surface by the Carolina kimberlite, Pimenta Bueno Kimberlitic Field, which is located on the southwestern border of the Amazonian Craton. We also present Sr-Nd isotopic data of garnet xenocrysts and whole-rocks from the Carolina kimberlite. Mantle xenoliths are mainly clinopyroxenites and garnetites. Some of the clinopyroxenites were classified as GPP–PP–PKP (garnet-phlogopite peridotite, phlogopite-peridotite, phlogopite-K-richterite peridotite) suites, and two clinopyroxenites (eclogites) and two garnetites are relicts of an ancient subducted slab. Temperature and pressure estimates yield 855–1102 C and 3.6–7.0 GPa, respectively. Clinopyroxenes are enriched in light rare earth elements (LREE) (LaN/YbN = 5–62; CeN/SmN = 1–3; where N = primitive mantle normalized values), they have high Ca/Al ratios (10–410), low to medium Ti/Eu ratios (742–2840), and low Zr/Hf ratios (13–26), which suggest they were formed by metasomatic reactions with CO2-rich silicate melts. Phlogopite with high TiO2 (>2.0 wt.%), Al2O3 (>12.0 wt.%), and FeOt (5.0–13.0 wt.%) resemble those found in the groundmass of kimberlites, lamproites and lamprophyres. Conversely, phlogopite with low TiO2 (<1.0 wt.%) and lower Al2O3 (<12.0 wt.%) are similar to those present in GPP-PP-PKP, and in MARID (mica-amphibole-rutile-ilmenite-diopside) and PIC (phlogopite-ilmenite-clinopyorxene) xenoliths. The GPP-PP-PKP suite of xenoliths, together with the clinopyroxene and phlogopite major and trace element signatures suggests that an intense proto-kimberlite melt metasomatism occurred in the deep cratonic lithosphere beneath the Amazonian Craton. The Sr-Nd isotopic ratios of pyrope xenocrysts (G3, G9 and G11) from the Carolina kimberlite are characterized by high 143Nd/144Nd (0.51287–0.51371) and eNd (+4.55 to +20.85) accompanied with enriched 87Sr/86Sr (0.70405–0.71098). These results suggest interaction with a proto-kimberlite melt compositionally similar with worldwide kimberlites. Based on Sr-Nd whole-rock compositions, the Carolina kimberlite has affinity with Group 1 kimberlites. The Sm-Nd isochron age calculated with selected eclogitic garnets yielded an age of 291.9 ± 5.4 Ma (2 r), which represents the cooling age after the proto-kimberlite melt metasomatism. Therefore, we propose that the lithospheric mantle beneath the Amazonian Craton records the Paleozoic subduction with the attachment of an eclogitic slab into the cratonic mantle (garnetites and eclogites); with a later metasomatic event caused by proto-kimberlite melts shortly before the Carolina kimberlite erupted.
Isótopos estáveis (C, O, S) e geoquímica de rocha total de carbonatitos da província Ígnea Alto Paranaíba – SE Brasil
(2016-09) Gomide, Caroline Siqueira; Brod, José Affonso; Vieira, Lucieth Cruz; Junqueira-Brod, Tereza Cristina; Petrinovic, Ivan Alejandro; Santos, Roberto Ventura; Barbosa, Elisa Soares Rocha; Mancini, Luis Henrique
The present work investigates the relationship between whole-rock geochemistry and stable isotope composition from carbonatites belonging to the Tapira, Araxá, Salitre, Serra Negra, Catalão I, and Catalão II alkaline-carbonatite complexes of the Alto Paranaiba Igneous Province (APIP), central Brazil and from the Jacupiranga Complex, of the Ponta Grossa Province, southeast Brazil. The APIP complexes are ultrapotassic, comprising bebedourites, phoscorites, nelsonites, and carbonatites, whereas Jacupiranga is a sodic complex composed of ijolite-series rocks, syenites, carbonatites, and alkaline gabbros. The geochemistry data allied to mineralogical constraints allowed us to classify the carbonatites into five groups, and to devise a chemical index (BaO/(BaO+SrO)) to gauge the magmatic evolution of the studied carbonatites.The APIP carbonatites evolve from apatite-rich calciocarbonatites toward Ba-, Sr-, and rare earth element (REE)-rich magnesiocarbonatites. This evolution is mostly driven by apatite, phlogopite, dolomite, and calcite fractionation and consequent enrichment in monazite, norsethite, and strontianite. Stable isotope data show a wide diversity of petrogenetic processes in play at the APIP, relatively to the Jacupiranga Complex, which is interpreted as a result of the shallower intrusion levels of the APIP complexes. Such shallower emplacement, at low lithostatic pressure, allowed for a complex interplay of fractional crystallization, liquid immiscibility, degassing, and interaction with hydrothermal and carbohydrothermal systems.
Variações composicionais de olivinas do complexo alcalino-carbonatítico de Salitre, MG
(2012-12) Barbosa, Elisa Soares Rocha; Brod, José Affonso; Cordeiro, Pedro Filipe de Oliveira; Brod, Tereza Cristina Junqueira
Compositional variation of olivines from Salitre alkaline-carbonatite complex, MG. The Salitre alkaline-carbonatite-phoscorite complex belongs to the Alto Paranaíba Igneous Province and consists of three separate bodies. Salitre I is a central, kidney-shaped body composed dominantly of bebedourites, with swarms of ring dykes of carbonatites and phoscorites; Salitre II and III are bebedourite-dominated smaller intrusions, respectively to the north and to the south of Salitre I. Olivine occurs in bebedourites, phoscorites and carbonatites, with forsterite content ranging from 83 to 98 mol. %. The least evolved rocks (bebedourites) show lower forsterite content than the more evolved members (phoscorites and carbonatittes), and olivine from carbonatites have the highest forsterite content. The compositional range of forsterite content observed in bebedourites is related to crystal fractionation. In phoscorites, forsterite content increases with decreasing whole-rock MgO, and in carbonatites it decreases, with the decreasing whole-rock MgO. Variations in CaO and MnO may occur in Salitre olivines. The controls of their distribution are unclear and may suggest local variations in the concentration of these elements in the magma, rather than a crystallographic control of olivine. NiO contents show differences between olivines from bebedourites, and olivines from phoscorites and carbonatites. This discrepancy may be related to the removal of Ni from the system by early fractionation of Ni-rich olivine from a silicate parental magma or, alternatively, by Ni removal in an immiscible sulfide liquid.
Utilização de uma ferramenta de simulação de sistemas na logística de uma empresa sucroalcooleira
(2015-08) Facchioli, Guilherme Péres; Severino, Maico Roris
It’s known that Goiás has been in a large growing of exportation, by the agricultural and livestock products. In this sense, companies must be aware of their logistics costs, which consume an estimable share of the total. So, it’s crucial to them have an efficient management’s system of the supply chain. On this, the paper shown based by a computational simulation system tool, the gains made by the sugar and alcohol company, when practices are adopted to coordinate its flow of matter and information.
Análise do tema economia solidária nas produções dos programas de pós-graduação em Geografia
(2015-07) Severino, Maico Roris; Barbosa, Janete Costa Ribeiro; Ribeiro, Marina Pires
The Solidarity Economy experiences have grown exponentially in Brazil since the start of the 21st century. To that extent, the various areas of knowledge have been developing studies to better understand this phenomenon, among them, Geography. The purpose of this paper is, therefore, to perform a quantitative and qualitative analysis of graduate programs productions (theses and dissertations) on geography and the solidarity economy topic. Hence, a literature review was conducted in order to gather all theses and dissertations up to the year of 2014, that addressed the topic. It was perceived that the geography research on the topic is still limited and regionally concentrated, but on the other hand, the studies analyzed show interesting analysis and broad scopes. The main contribution of this paper is the diagnosis of how the solidarity economy theme has been studied in geography, as well as to point out other research opportunities.
Guidelines to devise a multimodal freight transportation network in developing regions under economic growth approach
(2014-12) Almeida, Cristiano Farias; Gularte, Juliana Gomes; Yamashita, Yaeko
In Brazil, especially at the Amazon Region, the relationship between transport and economic development has been studied since 70s with elaboration of several plans. However, due to many factors, such as the incompatibility between the proposed models of transport planning and territorial planning, the expected results were not reached. Under these aspects, the goal of this paper is to define guidelines in order to devise a multimodal freight transportation network that allows efficient transport of products in a developing region. This network was developed using natural resources and it stimulates the economic growth and development based on the Growth and Development Poles Theory and Graphs Theory. As result three networks related to three different scenarios – status quo, investment in transport infrastructure by the governmental programs, and the strategy scenario – have been elaborated and analyzed considering the operational transport costs and their spatial configuration.
Identification of development poles on Brazilian Amazon region and analysis of the geographic accessibility
(2020-10) Santos, Alex Mota dos; Almeida, Cristiano Farias; Soares, Daniel de Oliveira; Silva, Carlos Fabricio Assunção da
Identification of development poles within the regional planning is important for defining the nodes of a given transport network and plays the role of driving economic growth in a region. Nevertheless, such proceedings are complex, especially in some areas where there is a lack of data that could support studies of this nature, for example in the case of the Amazon region. Thus, this study aims to identify development poles using spatial analysis of production values of soya, coffee, wood, and mineral products like cassiterite, aluminum ore, iron ore and copper. In addition, the geographic accessibility analysis was carried out at these poles in order to identify the potential of the transport network to be structured. Results demonstrated that it is possible to build a dense transport network by identifying more development poles, which would increase the connectivity, allowing more intense exchange of flows and development of the region.
Exploring the relationship between transportation infrastructure and regional economic growth using Losch’s location theory
(2021-05-14) Almeida, Cristiano Farias; Silva, Francisco Gildemir Ferreira da; Araujo, Paulo Henrique Cirino
There are some knowledge gaps regarding the relationship between transportation infrastructure and economic development, especially about economic impacts that occur due to implementation of infrastructure in a given region, albeit various studies have addressed the issue. This paper aims to identify variables that affect economic development in order to contribute to the development of a theoretical model that could explain the relationship between transportation infrastructure and economic development. The theoretical model is satisfactory because it begins by analyzing the actions generated by the transportation infrastructure. Moreover, the model is based on the Location Theory considering the economic development and taking into account variables such as transportation costs, gain, product value, consumption, competition between companies and lastly monopoly. Finally, an econometric procedure, Spatial Panel Auto Regressive Vector Model (PVAR), was used to evaluate the relationship between economic development and investments in transportation infrastructure.
Methodology focused on identifying variables necessary to develop logistics clusters
(2021-04-29) Almeida, Cristiano Farias; Yamashita, Yaeko; Cools, Mario; Marchal, Jean; Piette, Bernard
Using decision theory and evaluation system of agricultural land suitability to Identify aptitude of rail freight terminals
(2015-12) Almeida, Cristiano Farias; Yamashita, Yaeko; Carvalho, Willer Luciano
New service development process applied on air transport industry
(2020-06) Cualheta, Luciana Padovez; Caetano, Mauro; Almeida, Cristiano Farias
Objetivo do estudo: O objetivo desse estudo consiste em identificar as principais atividades do processo de desenvolvimento de novos serviços (PDNS) aplicáveis às empresas de transporte aéreo; Metodologia / abordagem: Várias atividades do PDNS foram identificadas na literatura, sendo elaborado um modelo conceitual, cujas atividades foram confrontadas com a realidade a partir de estudos de casos múltiplos realizados; Originalidade / relevância: A indústria de serviços de transporte aéreo é altamente relevante para a economia global e cresceu cerca de 6 vezes mais que o PIB global nos últimos anos. Apesar disso, nota-se que limitações gerenciais na oferta de novos serviços tem sido identificadas no setor; Principais resultados: A partir do desenvolvimento de um modelo conceitual aprimorado a partir de casos práticos, os resultados propoem um modelo de processo de desenvolvimento de novos serviços aplicáveis ao transporte aéreo; Contribuições teóricas / metodológicas: Ao se comparar os resultados dos estudos de caso com aqueles identificados na literatura, há atividades consideradas recorrentes na indústria de transporte aéreo, tais como a análise do ambiente externo e da capacidade financeira da empresa, bem como novas atividades do modelo, como mensuração da participação de mercado e identificação de novos consumidores; Contribuições sociais / gerenciais: Busca-se colaborar com o desenvolvimento de novos serviços que possam ser úteis não apenas na gestão da inovação das empresas, mas também que otimizem a eficiência no setor;
Correlações entre transporte e desenvolvimento econômico aplicadas ao turismo: uma análise a partir do município de Caldas Novas/Go - Brasil
(2017-12) Perim, Thiago Marcell Pires; Caetano, Mauro; Costa, Sérgio Henrique Barroca; Pimenta, Daiana Paula; Almeida, Cristiano Farias
Understanding the elements that potentiate the economic development of a certain locality becomes necessary in the managerial sciences and planning of touristic destinations. Collaborating with theoretical gaps related to the particular analysis of transport activities and their impact on tourism, this study seeks to identify the economic relations between tourism and road transportation of people in tourist cities, being adopted as a reference the case of Caldas Novas / Goiás / Brazil, one of the main tourist destinations in the country. From the use of economic data and the characteristic of people transportation, statistical models has been used to analyze, for example, the impact of the increase of vehicles to public transport at the gross domestic product of the municipality, demonstrating the levels of impact between the variables considered. Such results can be used to manage the transport activities and for the planning of tourism.
Metodologia para avaliação de rotas cicloviárias sob o enfoque da psicologia ambiental
(2021-12) Almeida, Cristiano Farias; Hamer, Luciana Joyce; Cools, Mario
This study aimed to develop a methodology for evaluation of cycle routes through indicators and based on Environmental Psychology and the physical characteristics of the urban space. For the study of the people behavior in the urban environment, the legibility and apprehension parameters of the "place" were adopted in addition to the foundations presented by Environmental Psychology: personal space, territoriality, privacy and density/crowding in its relation with cycling. The variables presented were measured through the Hierarchical Analysis in order to evaluate the Via Condition Index, which enabled the definition of a more efficient segment in a road network1 to compose the cycling system. The methodology is composed of the following steps: area delimitation, characterization of the area of study, identification of the segments with greater potential for trips with bicycles, evaluation of the condition index of the route, analysis of intervention opportunities and choice of the stretch of implementation. A case study was carried out in the city of Goiânia in order to validate the presented methodology. Thus, it is intended to assist managers and professionals in decision making regarding the implementation of cycle routes within a behavioral perspective.

Navegar

Submissões Recentes