Caracterização hidroquímica dos sistemas aquíferos Serra Geral e Guarani da sub-bacia do Rio Pardo e municípios adjacentes, no sudoeste do estado de São Paulo

The main purpose of this work is to evaluate the chemical composition of the groundwaters from Guarani Aquifer System and Serra Geral Aquifer System in the Rio Pardo basin, located at the southwestern of São Paulo state. To the hydrochemical characterization, physicalchemical analyses from 32 sampled wells were used. These results were plotted in Piper diagrams allowing the classification of groundwater as calcium or calcium-magnesium bicarbonate type and sodium bicarbonate type for both aquifer systems. Distribution of hydrochemical facies over the study area was obtained using Stiff diagrams. The groundwater can be classified, representing in this sequence its hydrochemical evolution. The recognized mechanisms responsible for groundwater evolution are dissolution of minerals magnesium, such as olivine, present in the basalt, dissolution of feldspars and removal of the carbonate cement of the sandstones mineral framework. Ionic exchange may represent an important processes in the groundwater evolution, responsible for the increase in the sodium concentration and decrease of calcium

Caracterização estrutural do Lineamento de Piúma e sua influência na porção norte da Bacia de Campos

The detailed study of the Brazilian continental margin basins became possible with the advancement of geophysical tools, with emphasis on seismic reflection. Characterizing the structural and stratigraphic elements of Brazil’s marginal basins they realized that there was a relationship with structures present on the adjacent continental basement. So many works began to be made to understand this relationship and know the major factors that influenced the evolution of the continental margin. The study area of this work includes the northern portion of the Campos Basin and the continental outcropping adjacent areas, which corresponds to the northern of Rio de Janeiro state and the southern of Espirito Santo state. This area stands an important structural feature of NW-SE direction with a projection to the Campos Basin called Lineamento de Piúma. The outcropping basement rocks belongs to the Ribeira Belt which was bonded to other mobile bands forming the continent Western Gondwana during the Brasiliano Cycle, which later fragmented giving rise to the Atlantic Ocean. The opening of the ocean results on the formation of the marginal basins of Brazil. These basins have continental, transitional and marine facies. On Campos Basin the continental phase resulted on the formation of horsts and grabens bounded by synthetic and antithetic faults. Continuing rifting formed the saline lakes that deposited siliciclastic and carbonate sediments. The transitional phase resulted on thick packages consist of evaporites (halite and anhydrite) that was deposited in lagoon environment, tectonically quiet arid and semi-arid. The marine phase it deposited siliciclastic and carbonate in the Campos Basin resulting in shales, marls, limestones, ritmito, turbidites, sandstones and others. The objective of this study is to investigate the possible continuation... (Complete abstract click electronic access below)

A cunha do ciclo de fácies do Grupo Guatá (Eopermiano) na margem sub-aflorante do norte paranaense

A wedge facies cycle it‟s a body of sedimentary rock, bounded above and below by unconformity and which represents a transgressive-regressive cycle of deposition. This cycle is formed by the following succession of facies: non-marine (N), transitional-coarse texture, and marine-fine texture; The objective of this study have been members of the sandstones and Triumph Siderópolis, seconded by rare calcareous sandstones and very thin limb Paraguaçu. Through analysis of facies in wells testified by CPRM, it was possible to group on facies successions and set the standard stacking. The Triunfo Member consists of three cycles of facies, lithology whose standard indicates a vertical arrangement ''type'' tuning up, other words, a component sandy bottom in the form of '' box'', followed by components sandy-clayey and clayey-carbonaceous (1st and 2nd cycle) and / or shale and limestone (3rd cycle), represented by the base member Paraguaçu. The first cycle only occurs on NF-5 wells and NF-6 in the form of Onlap channel dug in post-Itararé group. The cycle II also reaches wells NF-4 and NF-3 to the north, while the cycle III reaches the southern area, well NF-9. The member Paraguaçu, well PP-25 is predominantly clay-síltico, also stand out limestones and sandstones. The limestones are not coastal marine organisms probably connected with the algae and cyanobacteria, the sandstones are fine-textured, very thin and coastal deposition environment. The member Siderópolis, well NF-2 consists of a sandstone fluvial-estuarine deployed in the valley section, and succeeded by sandstones and siltstones bioturbed, they have linked the transgression of the Fm. Palermo

Litofácies e relações estratigráficas da formação Aquidauana no nordeste da Bacia do Paraná - São Sebastião do Paraíso (MG)

The Aquidauana Formation is characterized by sandstones of variable granulation, mudstones and diamectites abundant in clay, typical colors like brick red (vermelho tijolo) of glacial, fluvial and lacustrine origin. It’s chronostratigraphic equivalent to the Itarará group from the Neo Carboniferous age, that under the exploratory view, such units represent important intervals in the basin, occurring together with them minerals as well as energy resources as petroleum, underground water and coal – what requires a great paleogeography and stratigraphy knowledge for its exploration. By gathering information from the columnar sections of the area, it was possible to characterize the sedimentary facies, the stacking pattern as well as the association. It was also made an attempt of stratigraphic correlation, which showed great difficulties since glacial environments present a great lateral discontinuity of the facies besides the complex relationship process of formation. As a result, it was obtained 8 sedimentary facies, the lateral and vertical relations and genesis process. It is proposed that the sedimentary environment in the study area is the fluvio glacial, characterized by alluvial systems formed by defrosted water which transport the sediments that are deposited in plains in front of the glacier (distal outwash). Petrographic thin section analysis showed that the transportation process was ineffective. The grains present punctual to lobular contacts, characterizing good porosity and permeability to the rock, varying these qualities according to more or less existence of matrix. The presence of Iron Oxide deposited between the recrystallization border and feldspathic mineral indicates that this rock has possibly presented a primary rubefaction, intensified by alkaline fluid percolation

Simulação numérica de fluxo de águas subterrâneas na bacia do Rio Grande (BA)

The Urucuia Aquifer System represents a strategic water source in western Bahia. Its baseflow is responsible for the flow rate of the main tributaries of São Francisco river left bank in the dry season, including the Rio Grande, its main tributary in Bahia state. This river has a hydrological regime heavily affected by groundwater and is located in a region with conflicts about water resources. The aquifers geology is constituted by neocretacious sandstones of Urucuia Group subdivided in Posse Formation and Serra das Araras Formation. The embasement is formed by neoproterozoic rocks of Bambuí Group. This work focuses on an important tool application, the mathematical model, whose function is represent approximately and suitably the reality so that can assist in different scenarios simulations and make predictions. Many studies developed in this basin provided the conceptual model basis including a full free aquifer, lithological and hydraulical homogeneity in entire basin, null flux at plateau borders and aquifer base. The finite element method is the numerical method used and FEFLOW the computational algorithm. The simulated area was discretized in a single layer with 27.357,6 km² (314.432 elements and 320.452 nodes) totaling a 4.249,89 km³ volume. Were utilized 21 observation wells from CERB to calibrate the model. The terrain topography was obtained by SRTM data and the impermeable base was generated by interpolation of descriptive profiles from wells and electric vertical drilling from previous studies. Works in this area obtained mean recharge rates varying approximately from 20% to 25% of average precipitation, thus the values of model recharge zones varying in this range. Were distributed 4 hydraulic conductivity zones: (K1) west zone with K=6x10-5 m/s; (K2) center-east zone with K=3x10-4 m/s; (K3) far east zone with K=5x10-4 m/s; e (K4) east-north zone with K=1x10-5 m/s. Thereby was incorporated to the final conceptual model...

Fácies, diagênese e arquitetura estratigráfica de reservatórios deltaico-lacustres da fase rifte (formação pendência), campo Serraria da Bacia Potiguar

Of the four lacustrine deltaic models, which were found in the Pendência formation, two are represented in the Serraria field. Respectively the deltaic models 1 and 3 shows the reservoir zones A and B. The Zone A is divided into six sub-areas. Each is representing a smaller cycle of development of sigmoidal lobes of deltaic front. Zone B produces in reservoirs of Model 3, or so called Full delta. The Zone B is formed by overlapping the deltaic plain system over the deltaic/prodeltaic front (model 1). This work uses the method of zooming with the aim to contextualize the geometric aspects of the sand bodies, highlighting the analysis of facies and diagenesis with help of pictures and testimonies of thin sections. The sigmoidal lobes of Zone A are fine to very fine sandstones, well sorted, with a arcosian composition.;practically with a weak compaction and cementation of a kind of film of clay (if very fine) and overgrowth feldspar (fine texture). This silicate phases are succeeded by cementation of poiquilotópica calcite, and after this a stage of dissolution, containing only regular permoporosity for this reservoir. Zone B has a combination of two types of deltaic plain reservoir. One is the rarest of distributary channel and the other the most common of lobes of crevasse. In the channel coarse to medium-grained and poor to moderate sorted sandstones are formed (tuning up), and with a lytic arcosiana nature. Rarely there are cements, including growth of feldspar and rhombohedral dolomite, which prevent a high permoporosity of the reservoir. In the crevasse lobes, the sandstones are laminated, fine and well sorted, arkosic, rarely with overgrowth feldspar and calcite poiquilotópica, and with a good intergranular permoporosity

Geologia do platô N6 - província mineral de Carajás (SP)

The N6 Plateau presents an iron-ore occurence in Carajás Mineral Province, standing near to actually operating deposits. Geological mapping in 1:10,000 scale and integration of geochemical, geophysical, petrography and drilling turns possible interpretation of his geological evolution. The mapped area has lithotypes from Archean Grão Pará Group, comprising very lowgrade metamorphic basic rocks and iron formation and an Proterozoic sedimentary association of conglomeratic sandstones called as Caninana Unity. The structural geology in given by a regional scale homoclinal, where the Grão Pará Group strata dips towards SW, as a part of the Northern Limb of the Carajás Fold. Subsequent deformation associated to the installation of the Carajás Shear Zone presents as E-W fold axis. Geochemical evidence permits to consider de Parauapebas Formation as the rocks which has been hydrothermally-altered to outsourcing fluids responsible to deposition of iron formations in the oceanic system, including different signatures which can be interpreted as possible sub-embayments in the Carajás Basin. The iron ore in the area occurs in subsurface as very fine friable hematite generated by supergenous enrichment of the iron formation. The conceived geologic model differs from the current academic proposal on the fact that hydrothermal alteration has been involved on the jaspelite enrichment. Metamorphism on the Parauapebas Formation presents paragenesis considered as ocean-floor metamorphism which precedes de deformation insofar as the rocks show no tectonic fabric referring to shallow crust evolution. Geophysical methods such as magnetometry and gravimetry presents excellent results for structural interpretation in uneven exposed terrain

Mapeamento geológico-geontécnico de trecho da estrada vicinal na Serra de Itaqueri, Charqueada (SP)

Geological-geotechnical problems affecting escarps as well as embankment and fill slopes of roads and motorways may generate different types of unsteadiness, which are mainly arisen from the deficient knowledge about the physical environment. This results in unsuitable engineering projects and inadequate executions, which can be worsened by an occasional inappropriate maintenance of the construction. A geologically-geotechnically characterization of escarps and slopes is crucial in order to prevent these problems. This work deals with a geological-geotechnical study of 1:10.000 scale mapping in a stretch of a local road (CHQ-40) at the Serra de Itaqueri, Charqueada town, State of São Paulo. The stretch is known by several physical problems as erosion and mass movement. The methods of study were based on an integrative analysis of the diverse elements of the physical environment by using aerial photographs - to obtain the physiographic compartmentalization of terrain units - as well as field work - to accomplish the evaluation of the units by employing sketch lists. To achieve this, we selected several techniques in order to identify and classify different types of existing problems as erosion, landslide in embankments and fill slopes, rockfall, block rolling, among others. We also included the analysis of soil horizon, thickness and composition. The geological-geotechnical mapping resulted in six units: 1- Sandstones in cuesta’s backhill; 2 – Basalts in cuesta’s front; 3- Sandstones in cuesta’s front; 4 – Talus and colluvial deposits at cuesta’s foothill; 5- Sandstones of the Piramboia Formation in hillside; and 6 – Colluvial soil in the hill top. A characterization of the geological-geotechnical units is detailed, coupled to the cartographic material. Other cartographic products elaborated for this study included 1:10.000 maps of hypsometry, slope and curvature

Quimioestratigrafia do vulcanismo ácido mesozóico da província magmática do Paraná: porção SE do estado de Santa Catarina

The Mesozoic acid volcanism of the Paraná-Etendeka Province can be considered as one of the biggest events of its kind in the Earth's surface, and its study have attracted special interest in characterizing the end of magmatism that preceded the rupture process and the formation of continental Africa and South America Although significant, the acid volcanism featuring Members Chapecó Palmas and Serra Geral Formation represents only 2.5% of the total generated by the magmatic rocks and perhaps therefore the existing literature on these rocks is well less significant than that on the basalts. However, there are still aspects still unclear about the origin and evolution of these rocks in relation to the associated basalts. Thus, two profiles were selected, called RA and TA, which be a systematic collection of samples from the base where the Botucatu Formation sandstones occur at the top, where they observe Palmas acid rock type. These samples should be analyzed for major, minor and trace elements and treated in specific diagrams to define the vertical variation lithochemistry and their possible relationships with the associated basalts

Sucessão estratigráfica do Andar Alagoas na Serra do Tonã, Bacia do Tucano (BA)

STRATIGRAPHIC SUCCESSION OF ALAGOAS STAGE ON SERRA DO TONÃ, TUCANO BASIN (BAHIA). Located in northeast of Bahia, serra do Tonã is a NS elongated plateau that standsout in the flattened relief of Tucano Basin. The stratigraphic succession belongs to the Aptian post-rift sequence of this basin. Based on facies analysis, vertical stratigraphic profiles and satelite images interpretation, three stacked stratigraphic units were recognized: (1) lower carbonate unit, composed by laminated limestones and breccias, 5 m thick, correlated with Camadas Batateira of Arripe Basin; (2) intermediate siliciclastic unit, 100m thick and made of sandstones exhibiting finning upward cycles, overlaid by mudstones and sandstones wich sedimentary structures suggest action of tidal currents and (3) upper carbonate unit, composed by laminated limestones, 2-10 m thick, related with Santana Formation, that record lacustrine environment with possible marine influence. Paleocurrent analysis indicates proviniance from north and paleoflows towards south, similar to the Aptian fluvial facies of Araripe Basin, showing that both basins integrated the same continental paleodrainage

Caracterização magnetométrica de Sill de diabásio na região de Limeira - SP

Pós-graduação em Geologia Regional - IGCE

Contexto deposicional da sequência Balbuena III (Maastrichtiano/ Daniano) da formação Yacoraite na sub-bacia metán-alemania, na região de Salta, Argentina

Pós-graduação em Geologia Regional - IGCE

Volcanological aspects of the northwest region of Parana continental flood basalts (Brazil)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Características químico-mineralógicas e cerâmicas da matéria-prima utilizada pelo polo cerâmico de Rio Verde de Mato Grosso, MG

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização magnetométrica do Sill de Limeira-SP

The purpose of this study is to characterize the geological subsurface structure of the diabase sill of the Paraná Magmatic Province intruded in the Itararé Group, located near the city of Limeira, in the east-central region of São Paulo state. The magnetometric method served as an important tool defining the igneous body in view of the great contrast between the physical properties of the diabase sill and the host sandstones. Previous cartographic data signaled in region a possible lateral continuity in subsurface, of the various sills that occur in the region. However, the magnetic data obtained herein indicate that the area of occurrence of this body is very restricted and independent of the others observed in the region. The analysis of the radial average power spectrum obtained allowed determine the interval of number of waves adequate for the separation of shallow and deep sources, and thus conclude that the sill of the Limeira region is located more than 100 m deep.