33 resultados para Geostatistical inversion
Resumo:
The present work has the main goal to study the modeling and simulation of a biphasic separator with induced phase inversion, the MDIF, with the utilization of the finite differences method for the resolution of the partial differencial equations which describe the transport of contaminant s mass fraction inside the equipment s settling chamber. With this aim, was developed the deterministic differential model AMADDA, wich was admensionalizated and then semidiscretizated with the method of lines. The integration of the resultant system of ordinary differential equations was realized by means of a modified algorithm of the Adam-Bashfort- Moulton method, and the sthocastic optimization routine of Basin-Hopping was used in the model s parameter estimation procedure . With the aim to establish a comparative referential for the results obtained with the model AMADDA, were used experimental data presented in previous works of the MDIF s research group. The experimental data and those obtained with the model was assessed regarding its normality by means of the Shapiro-Wilk s test, and validated against the experimental results with the Student s t test and the Kruskal-Wallis s test, depending on the result. The results showed satisfactory performance of the model AMADDA in the evaluation of the MDIF s separation efficiency, being possible to determinate that at 1% significance level the calculated results are equivalent to those determinated experimentally in the reference works
Resumo:
The aim of this work is to use a new technology in the treatment of produced wastewaters from oil industry. An unit for treat produced waters called UTMDIF, was designed, installed and operated in an industrial plant for treatment of effluents from oil industry. This unit operates by means of the method of separation of phase inversion and can become a promising alternative to solve the problem of oil/water separation. This method constitutes the basis of the working of a new design of mixersettler of vertical configuration which occupies small surface area. The last characteristic becomes specially important when there is limitation on the lay-out of the plant, for example, over maritime platforms to explore oil. This equipment in a semi-industrial scale treats produced wastewaters contaminated with oil at low concentrations (ranging from 30 to 150 mg/L) and throughputs of 320 m3/d (47,4 m3 m-2 h-1). Good results were obtained in oil/water separation which leads to the necessary specification to discharge those wastewaters. Besides, the non dependence of the efficiency of separation in spite of the salinity of the medium becomes the equipment an attractive new technology to treat wastewaters containing oil at low concentrations
Resumo:
This work aims to determine a better methodology to help predicting some operational parameters to a new design of mixer-settler on treating wastewater produced by petroleum industry, called MDIF (Misturador-Decantador à Inversão de Fases/ Mixer-Settler based on Phase Inversion MSPI). The data from this research were obtained from the wastewater treatment unit, called MSPI-TU, installed on a wastewater treatment plant (WTP) of PETROBRAS/UO-RNCE. The importance in determining the better methodology to predict the results of separation and extraction efficiency of the equipment, contributes significantly to determine the optimum operating variables for the control of the unit. The study was based on a comparison among the experimental efficiency (E) obtained by operating MSPI-TU, the efficiency obtained by experimental design equation (Eplan) from the software Statistica Experimental Design® (version 7.0), and the other obtained from a modeling equation based on a dimensional analysis (Ecalc). The results shows that the experimental design equation gives a good prediction of the unit efficiencies with better data reliability, regarding to the condition before a run operation. The average deviation between the proposed by statistic planning model equation and experimental data was 0.13%. On the other hand, the efficiency calculated by the equation which represents the dimensional analysis, may result on important relative deviations (up 70%). Thus, the experimental design is confirmed as a reliable tool, with regard the experimental data processing of the MSPI-TU
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Mesenchymal stem cells (MSCs) are known as a population of multi-potential cells able to proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat and stroma. Several applications of the study of EC can be emphasized the therapeutic techniques such as guided bone regeneration by implantation of EC in the affected site, without the need for bone grafts, using titanium as a vehicle. The process of cryopreservation is essential for the maintenance of cell cultures, since the cell line is frozen, it can be maintained in liquid nitrogen for an indefinite period and then thawed for therapeutic or experimental purposes. The aim of this study was to isolate a population of MSCs derived from the subendothelium of the umbilical vein human (MSCs-SUVH) to assess cytogenetic analysis by the possibility of appearance of chromosomal changes in two different situations: MSCs-SUVH regarding the process of cryopreservation and MSCs-SUVH grown on the surface of titanium. Flow cytometry analysis revealed that, this cell population was positive for the markers CD29, CD73 and CD90, but there was no expression of hematopoietic lineage markers, such as CD14, CD34 and CD45 and demonstrated capacity for osteogenic differentiation. The chromosomes obtained from the primary culture of MSCs-SUVH were analyzed by GTW banding technique, and results are described as guidelines to ISCN 2005. There was not the emergence of clonal chromosomal changes in the MSCs-SUVH in different situations analyzed. However one of the strings presented a balanced paracentric inversion, probably a cytogenetic constitutional alterations, which was present before and after the experimental situations that the MSCs-SUVH was submitted
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Cytogenetics analyses in fish are important because they compose a private group among the vertebrates, occupying a central position in the animal evolution. The Perciforms Order, dominant in the marine and freshwater environment, it constitutes a model potentially useful in the genetic evaluation of populations, as well as in the understanding of its evolutionary processes. In spite of this, cytogenetics studies in this great group is scarce, above all for the inhabitants of sandy bottom and pelagics habits. The present work proposed to contribute for the cytogenetic characterization of nine species of fish marine of sandy bottom of the coast of Rio Grande do Norte (Brazil), identifying the evolutionary patterns related to the karyotype in these species and the existence of filogenetics affinities between them and other Perciformes. The animals were collected in the beaches of the Redinha, Ponta Negra and Búzios (Coast of Rio Grande do Norte) and in Saint Peter and Saint Paul Archipelago. Later on they were submitted to the cytogenetics technical that consist of mitotic estimulation, obtaining of mitotics chromosomes, proceeded by techniques of conventional coloration (Giemsa) and chromosomic bands (Ag-RONs and C band). Diploid number and fundamental number equal to 48 were observed in most of the species: Menticirrhus americanus, Ophioscion punctatissimus, Pareques acuminatus (Sciaenidae); Chloroscombrus chrysurus (Carangidae); Echeneis sp. 2 (Echeneidae); Archosargus probatocephalus (Sparidae) and Orthopristis ruber (Haemulidae). Trachinotus goodei (NF=52) (Carangidae) and Echeneis sp. 1 (Echeneidae) (NF=54) presented variation in NF, staying constant a diploid number equal to 48. RONs was situated in pericentromeric position in whole the scianids, and in the species Echeneis sp. 2 (22° pair), O. ruber and A. probatocephalus (1° pair), coinciding with great heterocromatics blocks in M. americanus (1° pair), P. acuminatus (2° pairl) and O. ruber (1° pair). RONs was also located in the telomeric area of the short arm of the 5° and 11° acrocentrics pairs in T. goodei, 4° and 19° pairs of C. chrysurus, 1° pair (sm) of Echeneis sp. 1. The C band detected centromeric blocks in most of the chromosomes of the species of Sciaenidae, Carangidae and Echeneidae, with great blocks in A. probatocephalus (4° pair). Heterocromatic blocks in telomeric areas in submetacentrics of Echeneis sp. 1, and pericentromerics in M. americanus (1° and 8° pairs), O. punctatissimus (1° pair) and P. acuminatus (2° pair) were also observed. It is noticed a marked conservatism cromossomic in the species of the family Scianidae and Haemulidae in what says respect to the number of acrocentrics chromosomes and the location of RONs. Even so it is outstanding the presence of heterocromatinization events during the karyotypic evolution of this family. Already in the families Sparidae and Carangidae, the obtained results reaffirm examples of small variations structural resultants of inversion and translocation Robertsonian, as important mechanisms of diversification karyotipical, as well as a pattern numerical evolutionary conserved, also observed in representatives of Echeneidae of Atlantic in relation to Pacific. The presence of RONs multiple, observed in the species T. goodei and C. chrysurus seems to represent a character derived in the family Carangidae. The results for the species O. ruber and A. probatocephalus suggest the presence of possible geographical or climatic barriers among populations of NE of Brazil in relationship the one of the SE
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Broadly speaking, the concept of gene therapy involves the transfer of a genetic material into a cell, tissue, or organ in order to cure a disease or at least improve the clinical status of a patient. Making it simple, gene therapy consists in the insertion of functional genes into cells containing defective genes by substituting, complementing or inhibiting them. The achievement of a foreigner DNA expression into a population of cells requires its transfer to the target. Therefore, it is a key issue to create systems able to transfer and protect the DNA until it reaches the target, the vectors. The disadvantages related to the use of viral vectors have encouraged efforts to develop emulsions as non-viral vectors. In fact, they are easily produced, present controllable stability and enable transfection. The aim of this work was to develop an emulsion for gene therapy and evaluate its ability to compact nucleic acids by the development of a complex with the plasmid pIRES2-EGFP. The first step was to determine the Hydrophilic Lipophilic Balance (HLB) of the Captex® 355 (oily internal phase of the emulsion) through long and short term stability assays. Based on the results, emulsions composed of Captex® 355, Tween 20® and Span 60® with 10.7 HLB were produced by three different methods: phase inversion, spontaneous emulsification and sonication. The results showed that the lowest diameter and best stability of the emulsions were achieved by the sonication method. The cationic emulsions were made by adding DOTAP to the basic emulsion. Its association with pIRES2-EGFP was evaluated by electrophoresis. Several rates of emulsion and DNA were evaluated and the results showed that 100% of the complex was formed when the rate DOTAP/DNA(nmol/µg) was 130. In conclusion, the overall results show the ability of the proposed emulsion to compact pIRES2-EGFP, which is a requirement to a successful transfection. Therefore, such formulation may be considered a promising candidate for gene therapy
Resumo:
The Borborema Province (BP) is a geologic domain located in Northeastern Brazil. The BP is limited at the south by the São Francisco craton, at the west by the Parnaíba basin, and both at the north and east by coastal sedimentary basins. Nonetheless the BP surface geology is well known, several key aspects of its evolution are still open, notably: i)its tectonic compartmentalization established after the Brasiliano orogenesis, ii) the architecture of its cretaceous continental margin, iii) the elastic properties of its lithosphere, and iv) the causes of magmatism and uplifting which occurred in the Cenozoic. In this thesis, a regional coverage of geophysical data (elevation, gravity, magnetic, geoid height, and surface wave global tomography) were integrated with surface geologic information aiming to attain a better understanding of the above questions. In the Riacho do Pontal belt and in the western sector of the Sergipano belt, the neoproterozoic suture of the collision of the Sul domain of the BP with the Sanfranciscana plate (SFP) is correlated with an expressive dipolar gravity anomaly. The positive lobule of this anomaly is due to the BP lower continental crust uplifting whilst the negative lobule is due to the supracrustal nappes overthrusting the SFP. In the eastern sector of the Sergipano belt, this dipolar gravity anomaly does not exist. However the suture still can be identified at the southern sector of the Marancó complex arc, alongside of the Porto da Folha shear zone, where the SFP N-S geophysical alignments are truncated. The boundary associated to the collision of the Ceará domain of the BP with the West African craton is also correlated with a dipolar gravity anomaly. The positive lobule of this anomaly coincides with the Sobral-Pedro II shear zone whilst the negative lobule is associated with the Santa Quitéria magmatic arc. Judging by their geophysical signatures, the major BP internal boundaries are: i)the western sector of the Pernambuco shear zone and the eastern continuation of this shear zone as the Congo shear zone, ii) the Patos shear zone, and iii) the Jaguaribe shear zone and its southwestern continuation as the Tatajuba shear zone. These boundaries divide the BP in five tectonic domains in the geophysical criteria: Sul, Transversal, Rio Grande do Norte, Ceará, and Médio Coreaú. The Sul domain is characterized by geophysical signatures associated with the BP and SFP collision. The fact that Congo shear zone is now proposed as part of the Transversal domain boundary implies an important change in the original definition of this domain. The Rio Grande do Norte domain presents a highly magnetized crust resulted from the superposition of precambrian and phanerozoic events. The Ceará domain is divided by the Senador Pompeu shear zone in two subdomains: the eastern one corresponds to the Orós-Jaguaribe belt and the western one to the Ceará-Central subdomain. The latter subdomain exhibits a positive ENE-W SW gravity anomaly which was associated to a crustal discontinuity. This discontinuity would have acted as a rampart against to the N-S Brasiliano orogenic nappes. The Médio Coreaú domain also presents a dipolar gravity anomaly. Its positive lobule is due to granulitic rocks whereas the negative one is caused by supracrustal rocks. The boundary between Médio Coreaú and Ceará domains can be traced below the Parnaíba basin sediments by its geophysical signature. The joint analysis of free air anomalies, free air admittances, and effective elastic thickness estimates (Te) revealed that the Brazilian East and Equatorial continental margins have quite different elastic properties. In the first one 10 km < Te < 20 km whereas in the second one Te ≤ 10 km. The weakness of the Equatorial margin lithosphere was caused by the cenozoic magmatism. The BP continental margin presents segmentations; some of them have inheritance from precambrian structures and domains. The segmentations conform markedly with some sedimentary basin features which are below described from south to north. The limit between Sergipe and Alagoas subbasins coincides with the suture between BP and SFP. Te estimates indicates concordantly that in Sergipe subbasin Te is around 20 km while Alagoas subbasin has Te around 10 km, thus revealing that the lithosphere in the Sergipe subbasin has a greater rigidity than the lithosphere in the Alagoas subbasin. Additionally inside the crust beneath Sergipe subbasin occurs a very dense body (underplating or crustal heritage?) which is not present in the crust beneath Alagoas subbasin. The continental margin of the Pernambuco basin (15 < Te < 25 km) presents a very distinct free air edge effect displaying two anomalies. This fact indicates the existence in the Pernambuco plateau of a relatively thick crust. In the Paraíba basin the free air edge effect is quite uniform, Te ≈ 15 km, and the lower crust is abnormally dense probably due to its alteration by a magmatic underplating in the Cenozoic. The Potiguar basin segmentation in three parts was corroborated by the Te estimates: in the Potiguar rift Te ≅ 5 km, in the Aracati platform Te ≅ 25 km, and in the Touros platform Te ≅ 10 km. The observed weakness of the lithosphere in the Potiguar rift segment is due to the high heat flux while the relatively high strength of the lithosphere in the Touros platform may be due to the existence of an archaean crust. The Ceará basin, in the region of Mundaú and Icaraí subbasins, presents a quite uniform free air edge effect and Te ranges from 10 to 15 km. The analysis of the Bouguer admittance revealed that isostasy in BP can be explained with an isostatic model where combined surface and buried loadings are present. The estimated ratio of the buried loading relative to the surface loading is equal to 15. In addition, the lower crust in BP is abnormally dense. These affirmations are particularly adequate to the northern portion of BP where adherence of the observed data to the isostatic model is quite good. Using the same above described isostatic model to calculate the coherence function, it was obtained that a single Te estimate for the entire BP must be lower than 60 km; in addition, the BP north portion has Te around 20 km. Using the conventional elastic flexural model to isostasy, an inversion of crust thickness was performed. It was identified two regions in BP where the crust is thickened: one below the Borborema plateau (associated to an uplifting in the Cenozoic) and the other one in the Ceará domain beneath the Santa Quitéria magmatic arc (a residue associated to the Brasiliano orogenesis). On the other hand, along the Cariri-Potiguar trend, the crust is thinned due to an aborted rifting in the Cretaceous. Based on the interpretation of free air anomalies, it was inferred the existence of a large magmatism in the oceanic crust surrounding the BP, in contrast with the incipient magmatism in the continent as shown by surface geology. In BP a quite important positive geoid anomaly exists. This anomaly is spatially correlated with the Borborema plateau and the Macaú-Queimadas volcanic lineament. The integrated interpretation of geoid height anomaly data, global shear velocity model, and geologic data allow to propose that and Edge Driven Convection (EDC) may have caused the Cenozoic magmatism. The EDC is an instability that presumably occurs at the boundary between thick stable lithosphere and oceanic thin lithosphere. In the BP lithosphere, the EDC mechanism would have dragged the cold lithospheric mantle into the hot asthenospheric mantle thus causing a positive density contrast that would have generated the main component of the geoid height anomaly. In addition, the compatibility of the gravity data with the isostatic model, where combined surface and buried loadings are present, together with the temporal correlation between the Cenozoic magmatism and the Borborema plateau uplifting allow to propose that this uplifting would have been caused by the buoyancy effect of a crustal root generated by a magmatic underplating in the Cenozoic
Resumo:
This thesis describes the general behavior of the northern shore of the State of Rio Grande do Norte relating beach profile morphology with hydrodynamic and sedimentological parameters. The Macau and Serra Oil Field are inserted on this area and are under accelerated coastal erosion. At these oil fields are installed oil wells from PETROBRAS, nowadays located directly in the shoreline, under constant attacks of coastal processes (e.g. waves, tides and currents), which promote an intense morphodynamic variability of this sandy coast. The area was monitored for 24 months in three different stations (P01, P02 and P03). The methodology applied involved current techniques of beach profiles, hydrodynamical processes, remote sensing and geophysics. A synthesis of results obtained through the use of different time scales (monthly, lunar cycle, seasonal, annual) from a coastal dynamics study is presented. The average wind direction corresponded to 77ºAz (NE). The steepness of the berm and of the shoreface, as well as coastal current direction, do not present major changes, with an average of 36º for the steepness of the berm, 15º for the shoreface and 15º for the coastal current direction. This data set allows us to infer that the months of larger coastal erosion were November/2000 and April/2001, because of the largest wave parameter during this time. The months of worse coastal erosion in this area are related with the increasing wavy energy. This in turn, seems to be related to seasonal climatic variations, with the wave energy and tide currents speed increasing during months of minor precipitations (June to January). The months of worse coastal erosion were September and November, when the largest wave parameters and speed currents are measured in the area. Since these months are included on the period of minor precipitations, we related the coastal erosion to seasonal climatic variations. The results obtained during these 24 months of monitoring confirms a situation of accentuated erosion, mainly in Profile 03 (Barra do Corta-Cachorro), where the wave height, period, and coastal current speed are always larger than the values found in Profile 02 (Macau5). Probably these values are more expressive in Profile 03, because it does not present any natural structure of protection against the wave impacts, as the barrier island located at Ponta do Tubarão, or the sand banks in front of Macau5. The transport of the sediments occurs from East to West, and the sand accumulation is more pronounced on Profile 03 intertidal zone, where there are embrionary dunes in dryer months. The tidal currents speed, on the other hand, is more accentuated in the Macau5 area (Profile 02). At Ponta do Tubarão, the tidal currents presented a preferential direction for NE, at times of flood, currents and for NW, at times of ebb current; at Barra do Corta-Cachorro the direction of the currents were predominantly for NW, independent of the tide phase, coinciding with the preferential direction of the longshore current. This currents inversion at Ponta do Tubarão is attributed to the presence of the Ponta do Tubarão island barrier and by the communication channel of the lagoon with the sea. The tide currents are better observed in protected areas, as in the Ponta do Tubarão, when they present inversion in their direction accordingly to the flood and ebb tide. In open areas, as in Barra do Corta-Cachorro, the tide currents are overprinted by the longshore currents. Sediment analysis does not show important modifications in grain size related to seasonality (dry- and rainy seasons). On the foreshore and backshore zones, the sediments vary from fine to medium sand, while in the shoreface they very from fine to very sands. The grains are mostly spheres, varying from sub rounded to sub angled. Quartz is the main component alongside Feldspat and heavy minerals as accessory components. Biogenic content is also present and mainly represented by mollusks fragments. The calculated sediment transport show values around 100 m3/day. The morphodynamic studies indicated that this is a reflexive area from October to April, and intermediate from May to September. The Relative Tide Range-RTR for this area is 4 < RTR < 15, and so classified in the mixed wave-tide group. Having this exposed we can affirm that the more active natural factors in this area are the currents, followed by the tides and the winds. The anthropic factors are exclusively local and punctual (Macau and Serra Oil Field). Taking in account the economic importance of the area, as well as the intensity of coastal processes acting on this shore, it is important a continuity of the monthly environmental monitoring looking for variations on longer-period cycles. These data have been stored on the geo-referenced database of the projects MARPETRO and PETRORISCO (REDE 05), aiming to model the coastal and sea environment, susceptible to oil spills and their derivatives
Resumo:
This thesis deals with the sedimentological/stratigraphic and structural evolution of the sedimentary rocks that occur in the NW continental border of the Potiguar Basin. These rocks are well exposed along coastal cliffs between the localities of Lagoa do Mato and Icapuí, Ceará State (NE Brazil). The sedimentological/stratigraphic study involved, at the outcrop scale, detailed facies descriptions, profile mapping of the vertical succession of different beds, and columnar sections displaying inferred lateral relationships. The approach was complemented by granulometric and petrographic analyses, including the characterization of heavy mineral assemblages. The data set allowed to recognize two kinds of lithological units, a carbonate one of very restricted occurrence at the base of the cliffs, and three younger, distinct siliciclastic units, that predominate along the cliffs, in vertical and lateral extent. The carbonate rocks were correlated to the late Cretaceous Jandaíra Formation, which is covered by the siliciclastic Barreiras Formation. The Barreiras Formation occurs in two distinct structural settings, the usual one with nondeformed, subhorizontal strata, or as tilted beds, affected by strong deformation. Two lithofacies were recognized, vertically arranged or in fault contacts. The lower facies is characterized by silty-argillaceous sandstones with low-angle cross bedding; the upper facies comprises medium to coarse grained sandstones, with conglomeratic layers. The Tibau Formation (medium to coarse-grained sandstones with argillite intercalations) occurs at the NW side of the studied area, laterally interlayered with the Barreiras Formation. Eolic sediments correlated to the Potengi Formation overly the former units, either displaying an angular unconformity, or simply an erosional contact (stratigraphic unconformity). Outstanding structural features, identified in the Barreiras Formation, led to characterize a neocenozoic stress field, which generated faults and folds and/or reactivated older structures in the subjacent late cretaceous (to paleogene, in the offshore basin) section. The structures recognized in the Barreiras Formation comprise two distinct assemblages, namely a main extensional deformation between the localities of Ponta Grossa and Redonda, and a contractional style (succeeded by oblique extensional structures) at Vila Nova. In the first case, the structural assemblage is dominated by N-S (N±20°Az) steep to gently-dipping extensional faults, displaying a domino-style or listric geometry with associated roll-over structures. This deformation pattern is explained by an E-W/WNW extension, contemporaneous with deposition of the upper facies of the Barreiras Formation, during the time interval Miocene to Pleistocene. Strong rotation of blocks and faults generated low-angle distensional faults and, locally, subvertical bedding, allowing to estimate very high strain states, with extension estimates varying between 40% up to 200%. Numerous detachment zones, parallel to bedding, help to acommodate this intense deformation. The detachment surfaces and a large number of faults display mesoscopic features analoguous to the ones of ductile shear zones, with development of S-C fabrics, shear bands, sigmoidal clasts and others, pointing to a hydroplastic deformation regime in these cases. Local occurrences of the Jandaíra limestone are controled by extensional faults that exhume the pre-Barreiras section, including an earlier event with N-S extension. Finally, WNWtrending extensional shear zones and faults are compatible with the Holocene stress field along the present continental margin. In the Vila Nova region, close to Icapuí, gentle normal folds with fold hinges shallowly pluging to SSW affect the lower facies of the Barreiras Formation, displaying an incipient dissolution cleavage associated with an extension lineation at high rake (a S>L fabric). Deposition of the upper facies siliciclastics is controlled by pull-apart graben structures, bordered by N-NE-trending sinistral-normal shear zones and faults, characterizing an structural inversion. Microstructures are compatible with tectonic deformation of the sedimentary pile, burried at shallow depths. The observed features point to high pore fluid pressures during deformation of the sediments, producing hydroplastic structures through mechanisms of granular flow. Such structures are overprinted by microfractures and microfaults (an essentially brittle regime), tracking the change to microfracturing and frictional shear mechanisms accompanying progressive dewatering and sediment lithification. Correlation of the structures observed at the surface with those present at depth was tested through geophysical data (Ground Penetrating Radar, seismics and a magnetic map). EW and NE-trending lineaments are observed in the magnetic map. The seismic sections display several examples of positive flower structures which affect the base of the cretaceous sediments; at higher stratigraphic levels, normal components/slips are compatible with the negative structural inversion characterized at the surface. Such correlations assisted in proposing a structural model compatible with the regional tectonic framework. The strong neogenepleistocene deformation is necessarily propagated in the subsurface, affecting the late cretaceous section (Açu and Jandaíra formations), wich host the hydrocarbon reservoirs in this portion of the Potiguar Basin. The proposed structural model is related to the dextral transcurrent/transform deformation along the Equatorial Margin, associated with transpressive terminations of E-W fault zones, or at their intersections with NE-trending lineaments, such as the Ponta Grossa-Fazenda Belém one (the LPGFB, itself controlled by a Brasiliano-age strike-slip shear zone). In a first step (and possibly during the late Cretaceous to Paleogene), this lineament was activated under a sinistral transpressional regime (antithetic to the main dextral deformation in the E-W zones), giving way to the folds in the lower facies of the Barreiras Formation, as well as the positive flower structures mapped through the seismic sections, at depth. This stage was succeeded (or was penecontemporaneous) by the extensional structures related to a (also sinistral) transtensional movement stage, associated to volcanism (Macau, Messejana) and thermal doming processes during the Neogene-Pleistocene time interval. This structural model has direct implications to hydrocarbon exploration and exploitation activities at this sector of the Potiguar Basin and its offshore continuation. The structure of the reservoirs at depth (Açu Formation sandstones of the post-rift section) may be controlled (or at least, strongly influenced) by the deformation geometry and kinematics characterized at the surface. In addition, the deformation event recognized in the Barreiras Formation has an age close to the one postulated for the oil maturation and migration in the basin, between the Oligocene to the Miocene. In this way, the described structural cenario represents a valid model to understand the conditions of hydrocarbon transport and acummulation through space openings, trap formation and destruction. This model is potentially applicable to the NW region of the Potiguar Basin and other sectors with a similar structural setting, along the brazilian Equatorial Atlantic Margin
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Numerous studies have indicated that the Potiguar Basin is affected by Cenozoic tectonics. The reactivation of Cretaceous fault systems affect the post-rift units, witch include Neogene and overlying Quaternary sediments. In this context, the objectives of this thesis are the followings: (1) to characterize the effects of post-rift tectonics in the morphology of Apodi Mossoró-river valley located in the central portion of the Potiguar, (2) to characterize the drainage of the Apodi Mossoró river valley and investigate the behavior of their channels across active faults, and (3) to propose a geologic-geomorphological evolutionary model for the study area. This study used a geological and geomorphological mapping of the central part of the basin, with emphasis on the Quaternary record, luminescence dating of sediments, and geoelectric profiles of the area. The results reveal by maps of structural lineaments and drainage channels of the rivers form valleys that are affected by faults and folds. In Apodi-Mossoró valley, anomalies of channel morphology are associated with the deformation of the post-rift basin. These anomalies show the reactivation of major fault systems in the Potiguar Basin in Cenozoic. On a regional scale, can be seen through the vertical electric profiles that the Cenozoic tectonics is responsible for the elevation of a macro dome NE-SE-trending 70-km long and 50km wide and up to 270 above sea level. In this sector, the vertical electric profiles data show that the contact between the Cretaceous and Neogene rise more than 100m. This Is an important feature of inversion data obtained in this work showed that the deposits that cover the macro dome (Serra do Mel) have ages of 119 ka to 43 ka. In the river valley and surrounding areas Apodi-Mossoró ages vary between 319 ka and 2.7 ka. From these data it was possible to establish the correct geochronological posiconamento paleodepósitos of distinguishing them from the fluvial deposits of the Neogene (Barreiras Formation)
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The circadian behavior associated with the 24 hours light-dark (LD) cycle (T24) is due to a circadian clock , which in mammals is located in the hypothalamic suprachiasmatic nucleus (SCN). Under experimental conditions in which rats are espoused to a symmetric LD 22h cycle (T22) the two SCN regions, ventrolateral (vl) and dorsomedial (dm), can be functionally isolated, suggesting that each region regulates distinct physiological and behavioral components. The vl region regulates the locomotor activity and slow wave sleep (SWS) rhythms, while the dm region assures the body temperature and paradoxical sleep (PS) rhythms regulation. This research aimed to deepen the knowledge on the functional properties of circadian rhythmicity, specifically about the internal desynchronization process, and its consequences to locomotor activity and body temperature rhythms as well as to the sleep-wake cycle pattern in rats. We applied infrared motion sensors, implanted body temperature sensors and a telemetry system to record electrocorticogram (ECoG) and electromyogram (EMG) in two rat groups. The control group under 24h period LD cycle (T24: 12hL-12hD) to the baseline record and the experimental group under 22h period LD cycle (T22: 11hL- 11hD), in which is known to occur the uncoupling process of the circadian locomotor activity rhythm where the animals show two distinct locomotor activity rhythms: one synchronized to the external LD cycle, and another expressed in free running course, with period greater than 24h. As a result of 22h cycles, characteristic locomotor activity moment appear, that are coincidence moments (T22C) and non coincidence moments (T22NC) which were the main focus or our study. Our results show an increase in locomotor activity, especially in coincidence moments, and the inversion of locomotor activity, body temperature, and sleep-wake cycle patterns in non coincidence moments. We can also observe the increase in SWS and decrease in PS, both in coincidence and non coincidence moments. Probably the increases in locomotor activity as a way to promote the coupling between circadian oscillators generate an increased homeostatic pressure and thus increase SWS, promoting the decreasing in PS
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It is presently assumed that the Borborema Province resulted from a complex collisional process associated with the convergent movement of plates, possibly involving amalgamation and accretion of microplates. This process was consolidated at the end of the Brasiliano event. It is investigated the possible limits for the tectonostratigraphic terranes in the northern portion of the province based on an integrated study of geological and gravity data. The study area comprises the portion of the Borborema Province located north of the Patos Lineament, limited by longitudes 33º00 W and 43º29 44"W and latitudes 1º36 S and 8º00 S. A revision of the regional geology allowed to identify areas presenting contrasting geological attributes, possibly representing different terranes whose limits are always shear zones of Brasiliano-age. The Sobral-Pedro II shear zone is the only one undoubtedly presenting geological attributes of sutures zones. The other shear zones are very likely associated with a geodinymic context of accretion, involving oblique collisions (docking), transcurrent and/or transforming sutures, and deep intracrustal shear zones. The gravity data contributed as a tool to identify strong lateral contrasts of density inside the upper crust possibly associated with crustal blocks tectonically juxtaposed. The dominant long wavelength anomaly in the Bouguer anomaly map is an expressive gradient, grossly parallel to the continental margin, caused by density variation across the crust-mantle interface in the transition from the continental crust to the oceanic crust originated by the separation between South America and Africa. Medium to small wavelength anomalies are due to intracrustal heterogeneities such as different Precambrian crustal blocks, Brasiliano-age granites and Mesozoic sedimentary basins. A regional-residual separation of the Bouguer anomaly map was performed in order to enhance in the residual map the effect due to intracrustal heterogeneities. The methodology used for this separation was a robust polinomial fitting. The inversion of residual gravity field resulted in a density contrast map (Δρ), in an equivalent layer that provided more accurated anomalies contours and consolidated the model which the sources of residual anomalies are located in the upper part of the present crust. Based on the coincidence of gravity lineaments in the residual map and Brasiliano shear zones, and using additional geological information, the following shear zones are proposed as limits between terranes: Patos shear zone, Sobral-Pedro II shear zone, Picuí-João Câmara shear zone, Remígio-Pocinhos shear zone, Senador Pompeu shear zone, Tauá shear zone, and Portalegre shear zone. Based on the geological/geophysical information it is attributed a higher level of confidence to the first three proposed limits(Patos, Sobral Pedro II, and Picuí-João Câmara shear zones). From west to east, these shear zones individualize the following terranes: Northwest of Ceará terrane, Central Ceará terrane, Tauá terrane, Orós-Jaguaribe terrane, Seridó terrane, and São José de Campestre terrane. In our study, the Rio Piranhas and Patos terranes are questioned because their previously proposed limits do not present good geological and gravimetric evidences. On the other hand, the previously proposed Cearense terrane is now subdivided into Central Ceará and Tauá terranes. Two residual gravity profiles located in the Seridó belt were interpreted using 2 ½ D direct gravity modeling. The main result of the modeling process is that all anomalies, with the exception of one, can be explained by outcroppring bodies, therefore restricted to the upper part of the present crust
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The history match procedure in an oil reservoir is of paramount importance in order to obtain a characterization of the reservoir parameters (statics and dynamics) that implicates in a predict production more perfected. Throughout this process one can find reservoir model parameters which are able to reproduce the behaviour of a real reservoir.Thus, this reservoir model may be used to predict production and can aid the oil file management. During the history match procedure the reservoir model parameters are modified and for every new set of reservoir model parameters found, a fluid flow simulation is performed so that it is possible to evaluate weather or not this new set of parameters reproduces the observations in the actual reservoir. The reservoir is said to be matched when the discrepancies between the model predictions and the observations of the real reservoir are below a certain tolerance. The determination of the model parameters via history matching requires the minimisation of an objective function (difference between the observed and simulated productions according to a chosen norm) in a parameter space populated by many local minima. In other words, more than one set of reservoir model parameters fits the observation. With respect to the non-uniqueness of the solution, the inverse problem associated to history match is ill-posed. In order to reduce this ambiguity, it is necessary to incorporate a priori information and constraints in the model reservoir parameters to be determined. In this dissertation, the regularization of the inverse problem associated to the history match was performed via the introduction of a smoothness constraint in the following parameter: permeability and porosity. This constraint has geological bias of asserting that these two properties smoothly vary in space. In this sense, it is necessary to find the right relative weight of this constrain in the objective function that stabilizes the inversion and yet, introduces minimum bias. A sequential search method called COMPLEX was used to find the reservoir model parameters that best reproduce the observations of a semi-synthetic model. This method does not require the usage of derivatives when searching for the minimum of the objective function. Here, it is shown that the judicious introduction of the smoothness constraint in the objective function formulation reduces the associated ambiguity and introduces minimum bias in the estimates of permeability and porosity of the semi-synthetic reservoir model
Resumo:
The Cumuruxatiba basin is located at the southern coast State of Bahia in northeastern of Brazil. This basin was formed in distensional context, with rifting and subsequent thermal phase during Neocomian to late Cretaceous. At Cenozoic ages, the Abrolhos magmatism occurs in the basin with peaks during the Paleocene and Eocene. In this period, there was a kinematic inversion in the basin represented by folds related to reverse faults. Structural restoration of regional 2D seismic sections revealed that most of the deformation was concentrated at the beginning of the Cenozoic time with the peak at the Lower Eocene. The post-Eocene is marked by a decrease of strain rate to the present. The 3D structural modeling revealed a fold belt (trending EW to NE-SW) accommodating the deformation between the Royal Charlotte and Sulphur Minerva volcanic highs. The volcanic eruptions have caused a differential overburden on the borders of the basin. This acted as the trigger for halokinesis, as demonstrated by physical modeling in literature. Consequently, the deformation tends to be higher in the edges of the basin. The volcanic rocks occur mainly as concordant structures (sills) in the syn-tectonic sediment deposition showing a concomitant deformation. The isopach maps and diagrams of axis orientation of deformation revealed that most of the folds were activated and reactivated at different times during the Cenozoic. The folds exhibit diverse kinematic patterns over time as response to behavior of adjacent volcanic highs. These interpretations allied with information on the petroleum system of the basin are important in mapping the prospects for hydrocarbons
Resumo:
The gravity inversion method is a mathematic process that can be used to estimate the basement relief of a sedimentary basin. However, the inverse problem in potential-field methods has neither a unique nor a stable solution, so additional information (other than gravity measurements) must be supplied by the interpreter to transform this problem into a well-posed one. This dissertation presents the application of a gravity inversion method to estimate the basement relief of the onshore Potiguar Basin. The density contrast between sediments and basament is assumed to be known and constant. The proposed methodology consists of discretizing the sedimentary layer into a grid of rectangular juxtaposed prisms whose thicknesses correspond to the depth to basement which is the parameter to be estimated. To stabilize the inversion I introduce constraints in accordance with the known geologic information. The method minimizes an objective function of the model that requires not only the model to be smooth and close to the seismic-derived model, which is used as a reference model, but also to honor well-log constraints. The latter are introduced through the use of logarithmic barrier terms in the objective function. The inversion process was applied in order to simulate different phases during the exploration development of a basin. The methodology consisted in applying the gravity inversion in distinct scenarios: the first one used only gravity data and a plain reference model; the second scenario was divided in two cases, we incorporated either borehole logs information or seismic model into the process. Finally I incorporated the basement depth generated by seismic interpretation into the inversion as a reference model and imposed depth constraint from boreholes using the primal logarithmic barrier method. As a result, the estimation of the basement relief in every scenario has satisfactorily reproduced the basin framework, and the incorporation of the constraints led to improve depth basement definition. The joint use of surface gravity data, seismic imaging and borehole logging information makes the process more robust and allows an improvement in the estimate, providing a result closer to the actual basement relief. In addition, I would like to remark that the result obtained in the first scenario already has provided a very coherent basement relief when compared to the known basin framework. This is significant information, when comparing the differences in the costs and environment impact related to gravimetric and seismic surveys and also the well drillings