This dissertation investigates the Pre-Albian mafic magmatism of the Santos Basin Pre-Salt sequence, associated with the rifting of Gondwana and the opening of the South Atlantic. The study integrates petrographic, stratigraphic, and geochemical data from two igneous sections of wells 3-BRSA-1290-SPS and 3-BRSA-883-RJS. The results demonstrate that the magmas from both wells are predominantly tholeiitic, with the exception of an alkaline sample (4923) in well 3-BRSA-883-RJS. Petrogenetic modeling indicates melting in the spinel zone, with depths between 44 km and 68 km, varying between wells: 63 km - 68 km for 3-BRSA-1290-SPS and 44 km - 51 km for 3-BRSA-883-RJS. The compositional distinction between the wells, separated by only 120 km, demonstrates mantle heterogeneity on an intra-basin scale, with the Southern well (3-BRSA-1290-SPS) deriving from enriched sources (E-MORB/OIB) and the Central well (3-BRSA-883-RJS) from more depleted sources (N-MORB to E-MORB), acting as markers of local tectonic segmentation during the rifting of Gondwana. The differentiation processes were predominantly governed by fractional crystallization in closed systems or with limited recharge (RFC), as demonstrated by the models applied to the sample pairs 6200-6185 and 5066-4904. AFC modeling indicates that crustal assimilation processes were restricted to specific samples (such as those from pairs 5025-4916 and 5066-4904), where they occurred with low assimilation rates (r = 0.2). The compositional diversity observed between wells is primarily attributed to the fusion of heterogeneous mantle domains at different depths in the spinel zone, with differentiation acting as a secondary process of mantle signatures. Academically, the results quantitatively validate the importance of mantle heterogeneities and lithospheric segmentation during the rifting of Gondwana, demonstrating that enriched (EM1) and depleted (DMM) domains coexisted in different sectors of the basin. From an exploratory standpoint, the petrogenetic definition of the 'Parati' (Post-Rift, enriched sources) and 'Tupi' (Rift, depleted sources) members offers geochemical criteria for mapping petroleum systems in the pre-salt province, conditioning the distribution of source rocks and reservoir architecture. Beyond their importance as chronostratigraphic markers, these events perform complementary exploratory functions: the first as an intrusive element (generation of traps and thermal maturation), and the second as a unit with reservoir/seal potential.

Geodiversity corresponds to the variety of geological environments, processes, and natural elements, such as rocks, minerals, fossils, and soils, to which cultural and intrinsic values are attributed, relating both to human history and to the importance of these elements in understanding the Earth itself. In this context, geoconservation extends beyond physical protection, recognizing geodiversity as a fundamental record of natural history preserved in rocks and landscapes. The definition of Heritage Stone, consolidated by the International Union of Geological Sciences (IUGS), reinforces the relevance of rocks used in historical constructions as essential cultural elements. In the Fluminense Paraíba Valley, the Além Paraíba Mylonite holds significant geological, historical, and cultural importance. Formed under conditions of intense metamorphism and tectonic deformation, this material was widely used in local historical constructions, especially during the 19th century, due to its availability and economic viability. Its use is directly associated with regional development during the coffee cycle, a period marked by economic expansion sustained by enslaved labor. Beyond its technical and aesthetic value, the mylonite constitutes an important link between geodiversity and the cultural identity of the Valley, being present in buildings, infrastructure, and historical landscapes. Thus, its recognition as a Heritage Stone contributes to the appreciation of regional memory and to the strengthening of geoconservation actions, integrating geological, historical, and cultural aspects.

The Santos Basin, located on the southeastern continental margin of Brazil and covering approximately 350,000 km2, records six magmatic events throughout its evolution. While the rift and post-rift megasequences are dominated by tholeiitic magmatism, the drift megasequence comprises three alkaline events: two in the Santonian–Campanian interval (85 75 Ma) and one in the Early Eocene (c. 50 Ma), occurring as both intrusive and extrusive rocks. This dissertation investigates a magmatic interval intersected in well 1-BRSA-886-RJS, in the northern portion of the Santos Basin, near the Cabo Frio High, between depths of 6,720.7 m and 6,521.5 m. The study aims to determine the intrusive or extrusive nature of this magmatism, its differentiation processes, its stratigraphic framework within the basin megasequences, and the mantle geodynamic mechanisms involved, through the analysis of 34 sidewall core samples. Petrography revealed a complex intercalation of igneous rocks, including gabbros, anorthosites, mesocumulatic olivine gabbros, mesocumulatic peridotites, and lamprophyres, interbedded with pelitic and carbonate rocks of the Barra Velha Formation. Lithogeochemistry characterizes the magmatism as alkaline to transitional, with compositions ranging from ultrabasic to intermediate. Most samples classify as gabbros, peridotitic gabbros, and monzogabbros, whereas two intermediate samples, a monzonite (with the highest incompatible element concentrations) and a syenite (richer in SiO2 and cumulatic in nature), represent the most evolved products. Geochemical modeling, applied exclusively to non-cumulatic samples, confirmed the cogenetic relationship and evolution by fractional crystallization among these rocks, while cumulates represent the complementary solid material accumulated in situ during the differentiation process. The physical intercalation of these lithotypes along the section reflects the synchronous operation of multiple differentiation mechanisms within the magma chamber, demonstrating that even relatively thin intrusions can record complex differentiation processes. 40Ar/39Ar dating obtained for three samples yielded ages of approximately 83 Ma, linking the studied magmatism to the Santonian–Campanian alkaline events of the Santos Basin. Isotopic data indicate two distinct and contemporaneous episodes of partial mantle melting: one generating the lamprophyric (monzogabbro) rocks and another producing the gabbroic suite. Binary mixing modeling reveals that the parental magmas derived from approximately 20% EMII-type mantle and 80% depleted mantle (DM), with monzogabbros exhibiting higher 87Sr/86Sr enrichment than gabbros. The results of partial melting modeling, combined with the obtained ages, indicate that a melting process in the garnet stability field was triggered during the Campanian in the Santos Basin. The proposed model assumes that lithospheric thinning combined with asthenospheric upwelling generated magmas that ascended and emplaced as a complex 300-meter-thick sill within the carbonates of the Barra Velha Formation.

The Morro de São João Alkaline Massif (MSJ), part of the Poços de Caldas–Cabo Frio Alkaline Alignment (PCCF), consists predominantly of syenites, exhibiting wide compositional variation represented by melanocratic, mesocratic, and leucocratic lithotypes. Unlike other alkaline massifs in the same alignment, the MSJ does not have significant outcrops, and its lithotypes are mainly recognized in blocks and boulders of different shapes and sizes, which, combined with the difficult access to the interior of the massif, limits the detail of the lithological mapping. In this study, the geophysical method of gamma spectrometry was used at different scales (aerial, field, and laboratory) to radiometrically characterize the massif and associate the distribution of K, Th, and U with the lithotypes present. The aerial and field data were processed using Oasis Montaj Student Version software, resulting in maps of the distribution of radioelements, as well as interpretive maps (ternary, F factor) and isotopic ratios. A good correlation was observed between the aerial and field surveys; however, the field data revealed localized variations not detected by the aerial surveys, attributed to the higher resolution and proximity to the source of the portable equipment. Laboratory analyses confirmed a pattern of enrichment in K, Th, and U directly related to the degree of magmatic evolution, in which melanocratic rocks have lower contents, while felsic rocks exhibit progressive enrichment, due to the incompatible behavior of these elements during magmatic differentiation. In addition, radiogenic heat production rates were estimated from data measured in samples and in the field, highlighting the contribution of radiogenic elements to the crustal thermal regime in the region.

Aquifer vulnerability studies have been developed in order to identify areas more susceptible to contamination. To this end, methods of vulnerability of aquifers to contamination are widely used, serving as a tool for the management of groundwater resources. The study area of this work corresponds to the Guandu-Mirim and Coastal Basins Hydrological Planning Units (UHPs), inserted in the Hydrographic Region II of the state of Rio de Janeiro. The study aims to map the vulnerability of aquifer contamination, of sedimentary and fractured types, through the integration of thematic maps, aerogeophysical data and field data using Geographic Information Systems (GIS's). wells were selected for graphics generation: static level, depth, maximum flow and specific flow, as well as for the application of the GOD methodology of aquifer vulnerability. After plotting the lineaments in the Digital Elevation Model, it can be observed that there are mainly lineaments in the NE-SW direction and, subordinately, in the NW-SE and E-W directions. The interpretation of aerogeophysical data showed that the lineaments obey the preferential direction NNE-SSW, at different depths and allowed to identify anomaly with dipole characteristic, that is, with the presence of a positive signal to the north/northeast/northwest with a low amplitude and a negative sign to the south/southeast/southwest with more intense amplitudes. The DEM and aerogeophysical data are excellent tools for delimiting lineaments.

Guanabara Bay is one of the most eutrophic tropical ecosystems in the world and is of
enormous importance, both locally and nationally. It is of great importance to properly manage the
availability of fresh water and reduce the levels of degradation of its quality, promoting the rational
use of water resources. In view of the scarcity of information regarding the hydrochemical analysis of
the Hydrographic Region V, this study aims to analyze the hydrogeochemical aspects of aquifersaround Guanabara Bay – RJ, as percolated by geological material, being possible to establish a spatial correlation between urban and industrial areas with the hydrogeochemistry of groundwater around RHV. 

Soil mapping is fundamental for the proper planning of activities related to land use, such as agriculture, the construction of roads and buildings, or the zoning of industrial areas, among others. However, soil mapping involves extensive and costly work, which often results in inefficient results. In this sense, digital soil mapping tools have been used to improve quality, measure the intrinsic error in soil maps, and with a better cost-benefit ratio. Some of the main characteristics and classifications of soils are influenced by factors in their formation, known as S.C.O.R.P.A.N. factors, which stand for Soil, Climate, Organisms, Relief, Parent Material, Age and Position. Digital elevation models (DEMs) and their derived data are the most widely used covariates to represent topographic conditions, playing an important role in digital soil mapping. Topographic features such as altimetry, slope, curvature and others that represent the relief of an area are effectively used to predict soil characteristics. As most existing soils are mineral soils, and their mineral composition reflects their properties and characteristics, the use of covariates that directly reflect characteristics of the parent material, such as Aero Geophysical Data (AGD), is justified in order to improve the quality of digital soil mapping (DSM). The aim of this study was to use topographic and aero-geophysical data to map the spatial distribution of soil classes in the Hydrological Planning Unit of the Guandu-Mirim River Basin and Coastal Basins, in Rio de Janeiro, Brazil. The Decision Tree and Random Forest predictive models that obtained the best statistical results used DAG as covariates and obtained overall accuracies of 0.87 and 0.97 respectively. Among the covariates derived from DAGs, uranium appeared among the 10 most important covariates for all the models that used DAGs. The results obtained indicate that the use of DAG as a representative of the source material formation factor can contribute to obtaining more accurate maps.

Campos Basin is located in SE Brazil, being among the most productive sedimentary basins regarding hydrocarbons in the country. Hydrocarbon production from volcanic reservoir rocks in Brazil is rare but it was succesfully achievied in the Badejo field, Campos Basin. The Badejo field is located southern Campos, about 75 km offshore SE the São Tomé Cape, in the continent, under 85 m of sea water. The volcanic rocks are basalts of the Cabiúnas Formation, related with the voluminous flows that erupted prior and during the Gondwana breakup in the Early Cretaceous. Despite their widespread distribution in Campos Basin, volcanic facies architectures and studies of physical volcanology regarding the Cabiúnas basalts are still scarce. The study area is 12 km2 and includes about 650 m of magmatic rocks of the Cabiúnas Formation. The aims of the study was to discriminate volcanosedimentary sequences in detail and to represent their distribution using concepts of physical volcanology and architecture of volcanic facies. The methods applied included usual systematics in petrological research as well as volcanic stratigraphy, with macroscopic description of well cores, optical microscopy and lithogeochemical analysis. The cores recovered from wells BD-02, BD-04 and BD-08, drilled in the Badejo field, provided an excelent material to reconstruct the 3D geometries of the volcanic flows in the area. Two Compound-braided flows (Sequence 1 and 3) and a Tabular-classic flow Sequence (Sequence 2) were identified in the studied wells. Morphologies or lithofacies associations include classical, hummocky, sheet and rubbly pahoehoe lavas. Coherent, brecciated, peperites and intertraps lithofacies were also described in the well cores. Effusion rates, based on the thickness of the lobes, indicated that pulsed inflation was the major process in Sequence 3. Minimum emplacement duration is estimated in 3 and 7 months for wells BD-2 and BD-04, respectively. Estimated D values for hummocky lavas are higher than those for classical pahoehoe lavas, pointing to porosities and permeabilities adequate to potential plays. Lithogeochemical data revealed a good correlation in the upper part of Sequence 3 indicating eruption from the same emission center. The compound-braided Sequence 2 may have reach 89.5 m, much thicker than the 40 m thick tabular-classical lavas in Sequence 3. The volcanic paleoenvironment corresponds to subaerial lava flows with humidity in all sequence. This information can be of great importance for better characterization of potential offshore volcanic reservoirs within Campos and other sedimentary basins associated with the Gondwana breakup in SE Brazil.

As printed form delivered to PPGMEG

Six magmatic sections interbedded with coquinas were sampled along well X drilled in Santos
Basin. Sidewall core samples from these magmatic sections were studied applying a
methodology divided in three main steps: analysis of well sections, petrography and
lithogeochemistry. The magmatic sections were taken as stacking miaskitic, alkaline basalt
flows, being time-related with the coquinas of the post-rift phase of Santos Basin. Geochimical
modelling showed that basalts from different magmatic sections are not cogenetic by
differentiation processes, except for the bottom section, indicating that the flows were erupted
from different vents. Modal batch partial melting models showed that the parental magmas can
derive from different amounts of partial melting from the same fertile source within the garnet
stability zone. However, this could only happen at extreme values within the wide range of
amounts of partial melting required to give rise to alkaline basalts. Therefore, derivation from
distinctive mantle sources should be kept in mind as a likely possibility for the petrogenesis of
these alkaline basalts. Binary mixing models showed that neither the subcontinental
lithospheric mantle nor the depleted mantle contributed to the petrogenesis of the alkaline
basalts. The lithogeochemica data indicate a role for the melting of the Tristan da Cunha plume
tail. Altogether, the petrogenesis of the alkaline basalts allow to propose a geodynamic model
for Santos Basin in which the Tristan plume tail melts beneath a strongly stretched continental
crust. This crust was not thick enough to support large magma chambers with long time of
residence so that crustal assimilation could take place. The petrogenetic and geodynamic
models imply in a shallow Moho and location of Santos Basin above a anomalous hot mantle
during the Aptian. The petrophysical data of the well profiles were qualitatively evaluated as a
means of test possible correlations with the petrographic data. Different values of gamma-ray,
resistivity, sonic, neutron porosity and bulk density may be related mainly with distinctive
structures of the basalts, such as brecciation, absence of amydales and amounts e sizes of the
amygadales.

The knowledge about soil attributes and hydropedology is important for studies that aim
understand the hydrological regime and monitoring water flow, especially in whatersheds,
where the stored and available water content affects both soils environmental functions, as well
as the biodiversity and the sustainability of this natural resource. In Brazil, soil databases have
few information collected about soil water parameters such as basic infiltration speed ratio (bir)
and saturated hydraulic conductivity (Ksat), due to the non-systematic performance of
infiltration tests at soil surveys and the difficulty of measuring such parameters in the
pedosphere`s deepest layers. In this context, it is possible to estimate the bir and Ksat by
associating the granulometric and physicochemical properties of the soil collected in the field,
by means of algorithms for quantitative pedology (Algorithms for Quantitative Pedology -
AQP) and implementation of pedotransfer functions using multivariate regressive analysis and
tree-based machine learning algorithms, capable of modeling them vertically (in profile) and
spatially at the study area. Still, as a way of expanding the information about the studied area
and guaranteeing a more reliable and robust modeling, it is desirable to associate measurable
parameters in the field and laboratory with other relevant information that help the analysis of
hydrographic basins, thus composing the input variables in the models mentioned. This study
suggests the application of variables from numerical modeling of the terrain, obtained through
the Digital Elevation Model (DEM), radiometric data, derived from environmental
aerogeophysics (aeromagnetometry and aerogamaespectrometry) and spectral analysis through
indices related to vegetation, soil and water using images from the Sentinel-2A sensor (spectral
indexes). The quantitative analysis and covariates selection, statistical-descriptive and
multivariate methods were applied, aiming to select potential covariates and the reduction of
dimensionalities and / or multicollinearity in the input variables in the models. Based on the
results obtained, the tree-based models (Random Forest - RF and Regression Trees - RT)
showed better performance in modeling the physical-hydric attributes when compared to the
regressive model to build pedotransfer functions. The multivariate approach using covariates
selection and dimensionality reduction methods allowed the optimized choice of input variables
in the modeling, elimination of multicollinearity problems, obtaining a diversified response to
the evaluated soil layers. The study shows the potential for integrating topographic, pedological
and radiometric data and their contribution to digital soil mapping and modeling, aiming at
understanding the variability of physical-hydric attributes in the studied watershed.