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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.
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.
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.
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.
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
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.
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.
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;
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.
Ações na escola para educação e segurança no trânsito
(Universidade Federal de Goiás, 2021) Santos (org.), Alex Mota dos
Methodology focused on identifying variables necessary to develop logistics clusters
(2021-04-29) Almeida, Cristiano Farias; Yamashita, Yaeko; Cools, Mario; Marchal, Jean; Piette, Bernard
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.
Relatório final do mapeamento geológico 1:50.000 da região de Anicuns (GO) - área 4
(Universidade Federal de Goiás, 2021-11-25) Messias, Davi Resende; Ramos, Lucas Portes; Sanchez, Joana Paula; Melo, Rodrigo Prudente de; Melo, Rodrigo Prudente de; Brod, José Affonso; Farias, Vanderlei de
This work was accomplished through the processing and the interpreting of images, geophysical, geochemical, and environmental data and lithological and structural data obtained in the field. The geological mapping in the Anicuns region had as result the outlining of units in the Goiás Magmatic Arc (AMG) context, including gneisses from the Sanclerlândia Metagranite and rocks from the Anicuns-Itaberaí Metavolcanosedimentary Sequence, units associated to sincollisional magmatism (Córrego da Lavrinha and Creoulos granites) and mafic rocks associated to volcanism installed through the collisional orogen collapse (Córrego Seco Complex), all comprising the Brasília Belt. Four deformational phases were recognised in the area: D1 represents an EW compression that generates folds verging East, which is refolded by D2, an EW compression from D1 progression; D3 is a NS lateral shortening that creates crenulation with an EW axis; D4 represents the ruptile last stage of the EW compression, with shear zones and thrust faults associated. The area is important in the understanding of the Brasília Belt evolution because its rocks are inserted in the tectonic and magmatic events related to the belt development, starting with the AMG formation in the Tonian Period, during the fracturing of the Rodinia Paleocontinent, and progresses until the Goiás Paleocean closure, when the last magmatic events occur. Economically, the area is interesting because of the presence of potential to numerous metallogenetic processes, including contact metamorphism, volcanism and hydrothermalism. The main mineral occurrences are gold and gravel.
Relatório final do mapeamento geológico 1:50.000 da região de Anicuns (GO) - área 1
(Universidade Federal de Goiás, 2021-11-25) Feitosa, Lara Maciel; Guimarães, Marco Tulio; Bezerra, Silvencler Batista; Sanchez, Joana Paula; Sanchez, Joana Paula; Rodrigues, Sérgio Wilians de Oliveira; Sanglard, Julio Carlos Destro
The detailing of the geology of the Anicuns region was made from a bibliographic survey combined with the processing and interpretation of photointerpretative, geophysical, geochemical, geoenvironmental and lithological and structural data collected in the field. The mapping made it possible to identify the lithotypes and group them into 10 lithostratigraphic units related to the Anicuns-Itaberaí Metavulcanosedimentary Sequence, Sanclerlândia Metagranite, Anápolis-Itauçu Granulitic Complex, Lage Granite, Córrego Santa Rosa Diorite, Taquaral-Trindade Suite and Cretaceous Dikes. Through the structural analysis, 3 deformational phases were identified, where D1 resulted in the main E-W shortening, pronounced in a set of regional folds with NNW axes, D2 generated N-S shortening that curved the regional folds in an orthogonal way. D3 represents the last stage (ductile-brittle) of EW compression, with the formation of shear zones and thrust faults. In general, the units are metamorphosed between the amphibolite facies to high green schist, associated with the Anicuns-Itaberaí Metavulcanosedimentary Sequence and locally there are rocks in granulite facies, associated with the Anápolis-Itauçu Granulitic Complex. The Córrego Seco body was defined in the geological mapping of the final 2020 work, consisting of rocks that allowed for the characterization of a volcanic system called Anicuns. This work also highlights the economic aspects of the area, including mineral occurrences with potential for metallurgy (manganese, iron), agriculture (calcitic marble) and civil construction (wollastonite, gravel, clay).
Relatório final do mapeamento geológico 1:50.000 da região de Anicuns (GO) - área 3
(Universidade Federal de Goiás, 2021-11-25) Aguiar, Pedro Guilherme do Carmo Gonçalves de; Gontijo, Rafael Ayres; Melo, Rodrigo Prudente de; Santos, Marcelo Henrique Leão; Santos, Marcelo Henrique Leão; Heringer, Rodrigo de Almeida; Reis, Mateus Andrade
This work presents the results of the 1:50,000 scale geological mapping, performed in Anicuns, Goiás. The region is located in the Brasília Belt context,inserted at contact between the Anicuns-Itaberaí Metavulcanosedimentary Sequence (AIS) and the Anápolis-Itauçu Complex (AIC). This mapping aimed to characterize the geological units, starting with the literature review, photolithological, geochemical and geophysical interpretations. After the field stage and petrographic description, six lithostratigraphic units were defined. The AIS has three units mapped in the area, the basic-ultrabasic unit, which include tremolite-talc-schists, tremolitites and amphibolites, some serpentinized with mineralogical assemblages indicating amphibolite facies; carbonated rhythmic unit, which includes intercalations of quartzite magnetite, metalimestones, marbles and metarrhythmites, affected by reverse faults associated with thrust zones; and, psamopelitic unit represented by intercalations between quartz mica-schists (with or without garnet) and quartzites. The AIC represents gneiss rocks that underwent retrometamorphism leaving the granulite facies to high amphibolite, in the area they are identified as amphibolite orthogneisses with a composition containing quartz, biotite, epidote, garnet, plagioclase, hornblende and pyroxene being uralitized; and amphibolite paragneisses represented by biotite-muscovite gneisses, muscovite-garnet gneisses, garnet-muscovite-biotite schist with or without sillimanite and calciosilicate gneisses. Finally, the Tonian granitegneisses represented by the granodiorite creoulos with porphyritic, leucocratic texture, rich in biotite and muscovite, with the presence of hornblende also being common. The entire area is affected by three deformation phases associated with the third event of the Brasiliana Orogenesis (~790-545 Ma).
Relatório final do mapeamento geológico 1:50.000 da região de Anicuns (GO) - área 02
(Universidade Federal de Goiás, 2021-11-25) Silva, André Luiz Gonçalves e; Assis, Túlio Moreira de; Nogueira Neto, José de Araújo; Nogueira Neto, José de Araújo; Nascimento, Estela Leal Chagas do; Souza, Valmir da Silva
The 1:50.000 scale geological survey of the Anicuns region (GO) consisted in mapping an area of 128 km2, inserted in the domain of the inner zone of the Brasília Belt. In terms of mapped units, the area is constituted by metabasic-ultrabasic and metasedimentary psamo-pelitic rocks of Anicuns-Itaberaí Metavulcanosedimentary Sequence overlapped on ortho- and paraderived gneiss rocks of Anápolis-Itauçu Complex. This entire set is intruded by syn-tectonic granitic rocks of Lage Granite and Córrego Santa Rosa Metadiorite. Basic dykes related to 125º azimuth and alluvial sediments complete the local stratigraphy. In structural terms, the area contains five deformational phases related to the Brasiliano Event (the first indicated by intrafolial folds): the second formed nappes with an eastward vergence (Sn and Sn+1 foliations), the third formed interference patterns due to the change in regional stress (Sn+2 foliation) and the fourth and fifth formed transcurrent faults and sinister shear zones (Sn+3 foliation). The metamorphism of the rocks of Anicuns Itaberaí Metavulcanosedimentary Sequence varies from greenschist facies to amphibolite facies. In the Anápolis-Itauçu Complex, the metamorphism reaches amphibolite facies conditions higher than the amphibolite/granulite facies transition. The tectonic compartmentation of mapping area is marked by lateral placement of rocks of different crustal levels, but which were submitted to the same phases of regional deformation, related to compressional processes with an eastward trend. The contacts between the mapped units were defined based on the tectono-stratigraphic relationships observed in the field, complementing them with information extracted from the photointerpretation and geophysical maps.
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.
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.
Mapeamento geológico-ambiental, em escala 1:25.000, de área adjacente ao reservatório do ribeirão João Leite, região metropolitana de Goiânia - Goiás
(Universidade Federal de Goiás, 2022-10-08) Álvares, Amanda Pereira; Silva, Ariele Lisita; Silva, Icaro Souza; Canile, Fernanda Maciel; Canile, Fernanda Maciel; Nogueira Neto, José de Araújo; Trindade Netto, Gil Barreto
The area under study comprises a peri-urban strip, located in the northwest region of the municipality of Goiânia, capital of the state of Goiás, which is part of the rural macro-zone of João Leite, an area destined for the preservation and sustainable use of its resources, under the influence of the Área de Preservação Permanente de João Leite (APAJoL). It is inserted in the geological context of the Anápolis-Itauçu Complex, belonging to the Brasília Belt, formed during the Brasiliana Orogeny in the Neoproterozoic. The objective of this work was to carry out an integrated mapping, in which the main aspects of the physical environment are related to geoenvironmental characteristics, based on the analysis of variables such as hypsometry, slope, drainage density, soil use and occupation, erosive susceptibilit, structural surveys, among others. Furthermore, in the area, four lithotypes belonging to the Anápolis-Itauçu Complex were characterized: i) garnet-hornblende-clinopyroxene-plagioclase granulite; ii) hypersthene gneiss, with presence of hornblende; iii) tremolithites, indicative of metasomatism; vi) quartzite metasedimentary sequence. The results obtained suggest that it is necessary to adopt inspection measures and control the advance of areas for agricultural purposes, implementation of allotments and residential condominiums that increase the deforestation of the Cerrado and cause erosion that cause silting and pollution of the rivers that supply the city.
Mapeamento geológico-geotécnico: mina de Barro Alto - GO, Anglo American
(Universidade Federal de Goiás, 2022-10-14) Santos, Lavoisier Matias dos; Arab, Paola Bruno; Rodrigues, Sérgio Wilians de Oliveira; Rodrigues, Sérgio Wilians de Oliveira; Temporim, Filipe Altoé; Lima, Martha Noélia
The Barro Alto Mafic-Ultramafic Complex is part of the Goiás Massif, which is inserted in the geological context of the Tocantins Province. The deformations associated to the amalgamation of Gondwana generated in the study area a series of structures and deformation stages. A schistose (S1) subparallel to the compositional banding (S0) is characterized. Boomerang-like refolding patterns associated with flexural slip mechanisms are also observed. Conjunctively, a NE-SW and NW-SE fracture system compatible with idealized fracturing models associated with cylindrical flexural folding are observed. The Barro Alto supergene nickel deposit is composed of lithological units derived from ultrabasic rocks - dunite-serpentinized, dunite boulder, base ore, acid ore, ferruginous ore, internal waste rock, soft chalcedony, hard chalcedony and laterite soil. Nickel extraction in Barro Alto is characterized by open pit mining, which consists of excavation of the soil or soft rock and consequent modification of the topography. These modifications must be technically planned, in order to optimize resources and increase safety levels. Saprolitized heterogeneous massifs are composed of reliquary structural features, rock blocks immersed in the weathered profile (bedrock), and irregular zones with contrasting weathering. These heterogeneities usually control the failure mechanisms and locations, as well as the factor of safety. For this work, in addition to good internal practices, the geological-geotechnical characterization was carried out based on the recommendations suggested by the ISRM and the criteria established by the RMR rock mass classification system (Bieniawski, 1989). The geological-geotechnical characterization indicated a rather heterogeneous and anisotropic massif. Furthermore, the simple kinematic analysis performed as a preliminary study obtained indices higher than 0.1 (10%) for planar and wedge type ruptures.

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