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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Originalité et développement du Paléolithique inférieur à l'extrémité occidentale de l'Eurasie : le Colombanien de Menez-Dregan (Plouhinec, Finistère) / Originality and development of the Lower Palaeolithic at the westernmost tip of Eurasia : the “Colombanian” of Menez-Dregan (Plouhinec, Finistère)

Ravon, Anne-Lyse 04 July 2017 (has links)
La variabilité des assemblages du Paléolithique inférieur dans l'ouest de l'Europe nourrit les débats actuels quant à leur relation avec les flux de populations, dans le contexte des changements environnementaux et paléogéographiques. Le faciès technique du Colombanien, localisé sur la façade atlantique bretonne, illustre cette variabilité. Selon la littérature, il diffère de l'Acheuléen, dominant dans les régions voisines, notamment par l'absence de bifaces. L'industrie du site de Menez-Dregan I (Plouhinec, Finistère) en constitue l'exemple dont le contexte géologique et paléoclimatique est le mieux documenté. Ce site a livré des traces de foyer qui sont parmi les plus anciennes d'Europe, ainsi qu'un abondant matériel, qui, dans les niveaux supérieurs, offre les prémices de la transition du Paléolithique inférieur vers le Paléolithique moyen. L'analyse des caractères techniques et typologiques des assemblages lithiques issus des couches 9 à 4 permettra de retracer l'évolution des stratégies d'approvisionnement et des comportements techniques et de replacer ce site dans le contexte régional et européen. La contemporanéité d’assemblages sans pièces bifaciales et à pièces bifaciales est attestée en Europe dès 700 ka. Si la plupart des sites européens présentent des assemblages à pièces bifaciales, les gisements à niveaux sans bifaces sont également assez nombreux. L’interstratification des niveaux à et sans pièces bifaciales sur certains sites est parfois interprétée comme le témoignage d’occupations liées à des activités spécialisées différentes, des matières premières différentes, ou des groupes humains aux traditions culturelles ou techniques différentes. De récentes publications de synthèse font état de la question : l’hypothèse de la coexistence de groupes humains aux traditions techniques différentes y est discutée, sur la base de modalités de débitage communes et d’utilisations similaires des territoires. Ainsi, seule la présence ou l’absence de bifaces tend à différencier ces occupations. Le travail engagé ici s’inscrit dans la lignée des études antérieures, mais a été entrepris dans le but de définir les systèmes techniques mis en œuvre au Paléolithique ancien dans l’ouest armoricain. Il permet ainsi de présenter des données nouvelles afin de caractériser les industries lithiques des sites dits « colombaniens ». Il ressort de notre étude que si le contexte paléogéographique et géologique ainsi que le type de gisement explique une certaine variabilité dans la composition des assemblages, cela n’explique pas les traditions techniques, et notamment la présence ou l’absence de pièces bifaciales ou de large cutting tools (LCTs). Si le type d’activité peut alors être mis en cause pour expliquer cette variabilité, une fréquentation répétée sur un même site, dans un contexte paléoenvironnemental globalement similaire, comme c’est le cas à Menez Dregan I indiquerait une visite régulière de groupes humains aux traditions techniques différentes, comme cela est aussi le cas sur d’autres gisements. Nous aboutissons ainsi à une révision du faciès Colombanien, qui s’avère être une variante régionale de l’Acheuléen. Ces résultats confrontés aux données paléoclimatiques et paléogéographiques contribuent à mieux comprendre la dynamique de peuplement de ce Finistère eurasiatique au Pléistocène moyen. / The variability in the Palaeolithic assemblages of western Europe feeds current debates about their relationship with population flows in a context of environmental and palaeogeographic changes. The technical Colombanian facies, located in the South Atlantic coast of Brittany, illustrates this variability. This facies differs from the Acheulean that is dominant in neighboring regions, especially in its lack of bifaces. The industry at the site of Menez-Dregan is an example where the geological and paleoclimatic context is the best documented in the region. Specifically, this site has yielded evidence of fireplaces that are among the oldest in Europe, and an abundance of lithic material, which, in the upper levels, evidences the beginning of the transition from the Lower Palaeolithic to the Middle Paleolithic. As for the analysis, the technical, typological and morpho-functional features of the lithic assemblages from layers 9 to 4 will trace the development of procurement strategies, techniques and behaviors to put this site into a regional and European context. The contemporaneity of assemblages with bifacial pieces and without bifacial pieces is attested in Europe from 700 ky. While most of the European sites display assemblages with handaxes, deposits without any bifacial components are quite numerous as well. On some sites, the interstratification of levels with bifacial pieces and without bifacial pieces is sometimes interpreted as a testimony of either specialized activities, different raw materials, or human groups with different cultural or technical traditions. Recent publications state the question: the hypothesis of a coexistence of human groups with different technical traditions is discussed, on the basis of similar modalities of debitage and similar use of landscape. Therefore, only the presence or absence of handaxes is left to differenciate these occupations. The work realised here joins in the lineage of the previous studies, but was undertaken with the aim of defining the technical systems operating during the Lower Palaeolithic in the western Armorican Massif. Therefore, it enables the presentation of new data in order to characterize the “Colombanian” lithic industries. It emerges from this study that if the palaeogeographical and geological context as well as the type of deposit explain a certain variability in the composition of the assemblages, it does not explain the technical traditions, especially the presence or absence of handaxes or large cutting tools. If the variability cannot be explained by activity alone then the repeated visits to a single site, given a globally similar palaeoenvironmental context as evidenced at Menez-Dregan I, likely indicates a regular occupancy by human groups with differing technical traditions. Therefore, we end up in a revision of the Colombanian facies, which turns out to be a regional variant of the European Acheulean. These results, when compared to paleoclimatic and palaeogeographic data, help develop a better understanding of the settlement dynamics of this region during Middle Pleistocene.
72

Étude multi-échelle des variations structurales, géochimiques et des propriétés magnétiques des coulées basaltiques prismées : exemple de la coulée de La Palisse (Ardèche) et de Saint-Arcons-d’Allier (Haute-Loire) / Multi-scale study of structural, geochemical and magnetic properties variations in columnar basalt flows : example of the La Palisse (Ardèche) and Saint-Arcons-d’Allier (Haute-Loire) basalt flows.

Boiron, Tiphaine 12 October 2011 (has links)
Des structures prismées sont fréquemment observées dans les coulées de lave comme la Chaussée des Géants (Irlande). Plusieurs théories existent pour expliquer ces formations, dont la plus répandue est celle de la contraction thermique. Or cette théorie permet difficilement de comprendre certaines observations de terrain comme la séparation fréquente des coulées en plusieurs niveaux. Afin de mieux comprendre la structuration au sein des coulées basaltiques, nous avons procédé à une étude pluridisciplinaire basée sur les propriétés magnétiques, les variations structurales et géochimiques de deux coulées prismées du Massif Central (La Palisse, Ardèche et Saint-Arcons-d’Allier, Haute-Loire). Notre approche permet de montrer que les fabriques cristallographiques et magnétiques sont gouvernées par l’écoulement de la lave. L’orientation du plagioclase contrôle la distribution des titanomagnétites à l’origine des fabriques magnétiques. Notre étude montre également que l’utilisation de l’ASM est un outil fiable pour déterminer l’orientation de l’écoulement à condition d’être contrôlée par des mesures de fabriques cristallographiques. Les mesures de la quantité d’eau et les analyses isotopiques (H et O) montrent que l’effet de l’altération météorique est faible et que l’eau contenue dans la roche est essentiellement de l'eau de constitution. De plus, à l’échelle du prisme, des variations de deuxième ordre sont observées comme celle des paramètres d’hystérésis qui indique des tailles de grains de titanomagnétites plus importantes vers le centre. Ces variations au sein du prisme semblent difficilement compatibles avec une structuration des coulées par la simple contraction thermique. / Columnar jointing is frequently observed in lava flows, as in the Giant Causeway (Ireland). The most common theory explaining the formation of prisms is by the thermal contraction. However, this theory hardly explains some field observations such as the frequent existence of three parts within the lavas flows, from the base to the top. To complete our understanding of the structuring lava flows, we carried out a multidisciplinary study based on the magnetic properties, structural and geochemical characterization of two basaltic flows from the French Massif Central (La Palisse, Ardèche and Saint-Arcons-d'Allier, Haute-Loire). Our approach shows that crystallographic and magnetic fabrics are governed by the flow. The distribution of titanomagnetite grains carrying the magnetic fabrics is mainly controlled by the plagioclase orientation. Our study also shows that the use of the AMS to determine the flow direction is a reliable tool, provided punctual control by measurements of crystallographic fabrics are performed. Measurements of the water content and isotopic analyses (H and O) show a limited weathering effect in the studied areas: rock water is mostly primary water in equilibrium with the magma. Moreover, second order changes are noted across the prism section such as hysteresis parameters associated to grain size variation of titanomagnetite (larger grains in the center). The variations of magnetic properties across the prism section suggest a gradient of the crystallization rate from the center to the edge of the prism, which seems difficult to reconcile with the structuring of the flow by thermal contraction only.
73

Historická ložiska cinabaritu v Čechách - genetická studie. / Historical cinnabar deposits in Bohemia - genetic study.

Velebil, Dalibor January 2010 (has links)
The study of fluid inclusions proved the metamorphic origin of the cinnabar-pyrite mineralization at the deposit of Horní Luby. In addition, thermal conditions of the mineralization formation were determined. During the deposit forming processes, the primary homogenous H2O-CO2 fluid of the temperature of about 300řC was differentiated to fractions rich in H2O or CO2. The differentiation took place in several stages in the temperature range between 200 to 150řC. Quartz crystallized from the parent fluid at the temperature about 300řC, pyrite at temperatures in the range of 220řC to 210řC and cinnabar at temperatures in the range of 195řC to 160řC. The cinnabar is thus the youngest mineral at the deposit (crystallization succession. quartz - pyrite - cinnabar). At the deposit of Jedová hora, quartz crystallized at the temperature of about 160řC to 150řC, barite at temperature of about 115řC (the fluid boiling point) and cinnabar in the range between these temperatures. The origin of mercury at all Czech historical deposit of cinnabar can be very likely related to Lower Paleozoic submarine volcanism. In all cases, the pre-concentrated mercury was remobilized during the Variscian metamorphosis, followed by precipitation in form of veins with cinnabar or as cinnabar impregnation. Study of tetrahedrite...
74

Geneze Au-Sb mineralizace na ložisku Krásná Hora / Genesis of Au-Sb ores at the Krásná Hora deposit

Němec, Matěj January 2014 (has links)
Ore deposits of the Krásná Hora ore district are the main representative of the Sb-Au mineralization in the Czech Republic. It can be classified genetically as epizonal subtype of orogenic gold deposits. Spatially and partly temporally are associated with the intrusion of the Central Bohemian Pluton. The ore bodies are related to quartz veins that follow the course of E-W striking lamprophyre dykes, which are usually heavily crushed and altered. Ore shoots with massive stibnite are located mainly at the intersections of these E-W trending veins with the NW-SE striking tectonic fault zones. Au-Sb ores at Krásná Hora ore district formed in an area of repeatedly activated fault zones. Three generations of hydrothermal quartz were identified on microscopic scale. Earliest quartz (Qtz1), which was considered in the literature auriferous originated from low-salinity H2O - CO2 fluids at ~350 řC and at a depth of about 5 km. The younger quartz (Qtz2) originated at lower temperatures of about 260 řC and lower depth of about 3-4 km from low/saline aqueous fluids. Both older (Qtz1) and younger quartz (Qtz2) are not auriferous. The gold is associated with younger paragenetic formation (Anti + Au + Cc + Qtz3) that fills in intergranular spaces and fractures in Qtz1 and Qtz2 . Due to the partial exhumation of the...
75

Variabilita chemického složení apatitů alkalických hornin Českého masívu / Variability of chemical composition of apatites from alkaline rocks of the Bohemian Massif

Mészárosová, Noemi January 2015 (has links)
III Summary This thesis is focused on crystal chemistry and crystal structure of apatites from alkaline rock of the Bohemian Massif. Fifteen samples of volcanic rocks, mostly of the Cenozoic age was selected for the study. Sample No. 5 is of the Silurian age. Sample No. 15 originates from volcanic rock of the Cenozoic age from the Slovak Western Carpathians. This sample was chosen for this study due to its substantially different chemical composition. The contents of major and minor elements in apatites were measured on an electron microprobe, the contents of some minor and trace elements were determined by laser ablation inductively coupled plasma mass spectrometry. Selected samples were investigated by cathodoluminescence (CL) spectrometry. Crystal structure of studied apatites was characterized by X-ray diffraction and Raman spectroscopy. It was found that dominant anion at position X is fluorine. The OH content calculated on the basis of the fully occupied position X is significant in some samples. The amount of Cl is generally low. The exception is the sample No. 15 where Cl reached up to 0.6 apfu (Z = 2). Studied apatites contain many substitutions but they are generally of minor extent. Strontium, iron and REE at position M belong to the most common and most important substituents for calcium in...
76

Stavby a mechanismy vmístění granitoidů typu Weinsberg (Moldanubický batolit) / Fabrics and emplacement of Weinsberg - type granitoids (Moldanubian Batholith)

Pour, Ondřej January 2012 (has links)
English abstract This diploma thesis is concerned with the brief introduction to the structures and fabrics in granitoid plutons. In the next part of this work are sumarized results of structural analyses of Weinsberg-type granite intrusion (Prášily and Strážný pluton) located in the SW part of high-grade rocks of the Moldanubian Zone. This research proceeded based on a combination of field structural data and results of AMS (Anisotropy of magnetic susceptibility) method. The emplacement and crystallization of both studied magmatic bodies took place in cooperation with the final phases of S3-fabrics development. This "bavarian phase" has a character of heterogenous deformation with indications of the dextral subhorizontal shear (WNW-ESE strike). During this event, syntectonic emplacement and internal fabrics development of strážný pluton took place at ~322 Ma. The transpression was followed by the localized transtension tectonics in NE direction, probably in cooperation with exhumation of high-grade metamorphic rocks of Bavarian terrane. In this phase, at ~320 Ma, the granitoids of Prášily pluton were emplaced into the considerably exhumed crust of the Moldanubian region.
77

Stavby a geodynamický vývoj ortorul moldanubika / Fabrics and geodynamic evolution of orthogneisses in the Moldanubian Zone

Kryl, Jakub January 2013 (has links)
Fabrics and geodynamic evolution of Moldanubian orthogneisses English abstract The aim of this paper is a structural analysis of selected mostly Cambro-Ordovician orthogneisses cropping out in a part of high-grade rocks of western Moldanubian Zone. These rocks have been affected by HT-MP/LP metamorphism and the polyphase deformation during the Variscan orogeny. In the blaník orthogneisses, (Qtz + Kfs + Plg + Bt ± Ms ± Sill ± Ky) an early deformation banding dips steeply to SSE to ESE. These fabrics were overprinted by NW to N gently dipping foliation with well developed stretching lineations plunging to W. Rare kinematic indicators (e. g. fold and pressure shadows asymmetry) reveal a strong subvertical contraction and stretching in the ~N-S direction. Based on the microstructural analysis this contractional event was connected with the activity of "Grain Boundary Migration Recrystallization" (GBM). Ductile shear zones dipping to E, locally ESE or ENE were identified. Bechyně orthogneisses (Qtz + Kfs + Plg + Bt ± Ms) is a N-S elongated body with the presence of regional pervasive metamorphic foliation dipping homogenously under low angles from SSW to WNW . These foliations bear well developed mineral or stretching lineation of quartz, biotite and feldspar aggregates plunging to ~SW. In the blaník orthogneiss...
78

Caracterização de áreas favoráveis à extração de blocos graníticos de grade porte com o uso da eletrorresistividade, Cabo de Santo Agostinho, PE / not available

Silva, Diego Daniel 24 October 2014 (has links)
Os métodos geoelétricos, principalmente a eletrorresistividade, estão sendo cada vez mais requisitados na área da mineração, indicando espessura de capeamento de solo, zonas fraturadas e heterogeneidades do material, viabilizando economicamente, ou não, um projeto minerário. Este trabalho, realizado no município do Cabo de Santo Agostinho -PE, apresenta e discute resultados de aplicações do método geofísico, da eletrorresistividade, como instrumento de auxílio na abertura de uma nova frente de lavra para extração de blocos graníticos de grande porte. Foi investigada a espessura do capeamento de solo, bem como as principais zonas locais de falhas e fraturas. Para isso foram realizadas 32 SEVs (03 SEVs por perfil, à exceção da Linha 11, com 02) com arranjo Schlumberger de AB/2 máximo de 60metros, e 11 caminhamentos elétricos com arranjo dipolo-dipolo de AB=MN=20 metros,com aproximadamente 1000m de extensão cada perfil. As SEVs foram dispostas nas linhas de modo a cobrir adequadamente a área do terreno, possibilitando a confecção de um mapa de contorno da profundidade do topo rochoso e a caracterização do perfil de alteração pedológico. Os caminhamentos elétricos foram dispostos paralelamente entre si e espaçados de 60 metros, podendo ser observadas as possíveis configurações do topo rochoso, como rocha não fraturada e zonas fraturadas. A partir dos dados dos caminhamentos elétricos foram elaboradas simulações 3D de resistividade e para a estimativa de volume de rocha não fraturada na área de estudo (com base nas resistividades mais elevadas).Os resultados obtidos mostraram a eficiência da eletrorresistividade na determinação do topo da rocha sã e detecção das zonas fraturadas no maciço granítico. / The geoeletric methods, especially electroresistivity, are being progressively more required on mining, for identifying soil thickness, fractured zones and geological heterogeneities, to check economical viability of mining projects. This work, held in Cabo de Santo Agostinho-PE city, presents and discusses geophysics application results of electroresistivity as a tool for helping the opening of a new granitic blocks exploitation front. The soil thickness was investigated, as well as the main local fault zones and fractures. A total of 32 VESs (03 VESs per section, exception made to line 11, with 02 VESs) using Schlumberger array with AB/2 maximum of 60 m, and 11 geoelectrical profilings using dipole-dipole array (AB=MN=20 m), with section lengths close to 1000 m. The VESs lines were organized in order to cover the studied area properly, allowing mapping the top of the rock massif and characterizing the soil profile. The geoelectrical profilings were disposed parallel with 60 m gap among each other, enabling the observation of the massif top configurations, such as fractured and non fractured zones. 3D resistivity simulations were performed using the geoelectrical profilings data in order to estimate the total volume of non fractured rock in the studied area (based on the highest resistivities). The obtained data showed the efficiency of electroresistivity for fractured zones detection and for mapping the top of the fresh rock massif.
79

Étude d'une structure d'inducteur supraconducteur à modulation de champ magnétique / Study of a superconducting inductor structure with magnetic field modulation

Malé, Gaël 02 October 2012 (has links)
Dans le domaine du génie électrique et plus particulièrement dans celui des moteurs électriques, un des principaux challenges à relever pour les années qui viennent est l'augmentation de la puissance et du couple massique. Un moteur synchrone fonctionne sur le principe de l'interaction de deux champs magnétiques. Un inducteur alimenté en courant continu crée un champ magnétique variable dans l'espace. L'induit produit quant à lui un champ tournant par l'intermédiaire d'un bobinage, principalement, triphasé. Le couple électromagnétique généré est fonction du produit du champ tangentiel (Ht) par le champ radial (Bn). On a alors la possibilité d'augmenter le couple d'une machine, soit en agissant sur Ht (produit par l'induit) ou en agissant sur Bn (produit par l'inducteur). L'inducteur est composé de deux solénoïdes supraconducteurs alimentés par des courants opposés qui créent une induction magnétique importante. La présence de plaques supraconductrices qui, par leur propriété d'écrantage du champ magnétique, module et canalise ces lignes de champ. C'est cette variation spatiale de l'induction qui permet de générer un couple mécanique. La structure de cet inducteur supraconducteur est susceptible En effet, Dans un moteur conventionnel, l'amplitude de l'induction dans l'entrefer est autour de 2 Teslas (de -1 Tesla à +1 Tesla). Les matériaux supraconducteurs permettent d'atteindre des niveaux d'induction magnétique que nous ne pourrions envisager avec les matériaux classiques. Cette structure offre la possibilité d'accroître cette valeur et par conséquent, de présenter un saut technologique en augmentant le couple dans les mêmes proportions. Le domaine d'application relève des moteurs embarqués d'une puissance comprise entre plusieurs MW et plusieurs dizaine de MW. Cependant, un des verrous technologiques restant est la possibilité de réaliser des écrans supraconducteurs de grande taille pour un inducteur de moteur de forte puissance (par exemple quelques dizaines de MW) / In the electrical engineering, especially in electric motors, one of the main challenges in the coming years is the increased of mass power and mass torque. A synchronous motor operates by the interaction of two magnetic fields. An inductor supplied with direct current creates a variable magnetic field in space. The armature produces a rotating field by a three-phase winding. The electromagnetic torque generated depends from the product of tangential field (Ht) by the radial field (Bn). The torque can be increased by acting on Ht (produced by the armature) or by acting on Bn (produced by the inductor). The inductor consists of two superconducting solenoids fed by opposed currents which create a huge magnetic induction. By using superconducting bulks which present magnetic screening property, we modulate this field. So, this spatial variation of induction generates a mechanical torque. Indeed, in a conventional engine, the amplitude of induction in the gap is around 2 Tesla (Tesla from -1 to 1 Tesla). Superconducting materials can exceed these levels of magnetic induction. This structure offers the possibility to increase this value and therefore to increase the torque in the same proportions and to present a technological leap. The application area is embedded engines for power between several MW and more. However, a technological limit is the possibility of making large superconducting screens for an inductor of large motors (eg a few tens of MW)
80

Processamento e interpretação de dados aeromagnéticos do Maciço Alcalino Ponte Nova (SP-MG) / Processing and interpretation of aeromagnetic data of the Ponte Nova Alcalino Massif (SP-MG)

Diego Prado Barroso 04 September 2018 (has links)
O Maciço Alcalino máfico-ultramáfico Ponte Nova localiza-se no setor norte da Província Serra do Mar, junto à porção oriental da Serra da Mantiqueira, na fronteira dos Estados de São Paulo e Minas Gerais. Caracteriza-se por dois afloramentos de áreas 5 km² e 1 km². Dados magnéticos obtidos dos aerolevantamentos realizados para a CPRM pela Microsurvey Aerogeofísica e Consultoria Científica Ltda evidenciaram a presença de uma anomalia magnética extensa e de grande amplitude sobre os afloramentos. Este trabalho apresenta os resultados da interpretação geofísica e de modelagem direta integrando os dados aeromagnéticos com dados geológicos e gravimétricos do maciço visando uma caracterização do maciço em subsuperfície. Para uma determinação mais eficaz da localização e das dimensões da fonte da anomalia magnética, foram utilizadas técnicas de redução ao polo, amplitude do sinal analítico da anomalia magnética de campo total e aplicação de derivadas direcionais. Em laboratório, foram medidas as susceptibilidades magnéticas e intensidade da magnetização remanente natural de 14 amostras retiradas da região. Os resultados confirmaram a presença de magnetização remanescente em algumas das amostras, e susceptibilidade magnética média da ordem de 10-2 SI. A partir da conjunção dos dados do aerolevantamento e de dados geológicos, foi feita a modelagem direta 3-D com as propriedades magnéticas parametrizadas pelas medidas em laboratório. Os modelos consideraram a discriminação das fácies petrográficas do maciço, com susceptibilidades magnéticas variando de 0,1 a 0,9 SI. Os corpos modelados atingiram profundidades da base de pelo menos 3 km e seus volumes foram da ordem de 25 km³. Com base nas dimensões obtidas nos modelos magnéticos diretos, foi realizado um modelo gravimétrico direto com valores de densidade variando entre 2,77 g/cm³ e 3,30 g/cm³. Os resultados obtidos pelos modelos diretos foram discutidos e comparados com o modelo geológico e com outros modelos gravimétricos desenvolvidos. Apesar dos resultados alcançados pelos modelos apresentarem valores compatíveis com os observados nos levantamentos, os modelos não permitiram discriminar entre as duas hipóteses de trabalho sobre a configuração do maciço em subsuperfície: um corpo único que aflora em duas regiões ou dois corpos desconectados em subsuperfície. / The Ponte Nova mafic-ultramafic alkaline massif is located in the northern sector of the Serra do Mar Province, near the eastern portion of the Serra da Mantiqueira, on the border of the states of São Paulo and Minas Gerais. It is characterized by two outcrops measuring 5 km² and 1 km² of area. Magnetic data obtained from the airborn surveys carried out for the CPRM by Microsurvey Aerogeofísica and Consultoria Científica Ltda. evidenced the presence of an extensive magnetic anomaly with great amplitude on the outcrops. This work presents the results of geophysical interpretation and direct modeling integrating the aeromagnetic data with geological and gravimetric data of the massif, aiming a characterization of the massif in the subsurface. To determine a better location and shape values of the magnetic anomaly\'s source, we use pole reduction techniques, amplitude of the analytical signal of the total field magnetic anomaly and directional derivative applications. Magnetic susceptibilities and natural remanent magnetization intensity of 14 samples from the region were measured in laboratory. The results confirm the presence of remanent magnetization in some samples, and the average magnetic susceptibility about 10-2 SI. From the conjunction of the aero-survey data and the geological data, two direct 3-D model were developed with the magnetic properties parameterized by the laboratory measurements. These models considered different petrographic facies, with magnetic susceptibilities ranging from 0.1 to 0.9 SI. The modeled bodies reached depths of the base of at least 3 km and their volumes were about 25 km³. Based on the dimensions obtained from direct magnetic models, a direct gravimetric model was performed, with density values ranging from 2.77 g / cm³ and 3.30 g / cm³. The results obtained by the direct models were discussed and compared with the geological model and with other existing gravimetric models. Although the direct models yielded results compatible with those observed in the surveys, the results do not allow for discrimination of the following working hypotheses on the configuration of the subsurface massif: a single body outcropping in two regions or two bodies disconnected in the subsurface.

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