Observations geologiques dans la region d'Ouro Preto (Minas Gerais, Bresil)

1951 ◽  
Vol S6-I (1-3) ◽  
pp. 31-34
Author(s):  
Boris Brajnikov
Keyword(s):  
Sedimentary Cover ◽  
Minas Gerais ◽  
Regional Structure ◽  
Local Displacement ◽  
The Core ◽  
Crystalline Core ◽  
Principal Directions ◽  
Secondary Interest

Abstract Mountain ridges of Precambrian sandstone or quartzite in the Ouro Preto region of Brazil follow three principal directions. It is not yet clear whether these formations represent the lower Algonkian Minas series or the middle Algonkian Itacolomi series. The regional structure consists of a crystalline core overlain by phyllites and quartzites. The sedimentary cover has been sheared along with the core and, caught up in movements of isolated blocks of the core, subjected to more or less intense local displacement and folding. The result is a checkerboard of faulted segments. The topography is primarily determined by the structure, with erosion effects of secondary interest.

Chemiluminescence emission in cholesteric liquid crystalline core–shell microcapsules

2014 ◽  
Vol 2 (25) ◽  
pp. 4904-4908 ◽  
Author(s):  
Y. Iwai ◽  
H. Kaji ◽  
Y. Uchida ◽  
N. Nishiyama
Keyword(s):  
Liquid Crystalline ◽  
Double Emulsion ◽  
Core Region ◽  
Middle Phase ◽  
The Core ◽  
Emulsion Droplets ◽  
Crystalline Core ◽  
Oil Water ◽  
Double Emulsion Droplets ◽  
Cholesteric Liquid Crystalline

Chemiluminescence behaviour in the core region of water/oil/water double emulsion droplets with cholesteric liquid crystalline middle phase was demonstrated.

scholarly journals Refinement of the petrophysical model of the Achimov formation based on facial analysis of sedimentation conditions

2021 ◽  
Vol 6 (4) ◽  
pp. 22-31
Author(s):  
Guzel R. Vahitova ◽  
Anzhela A. Kazaryan ◽  
Timur F. Khaybullin
Keyword(s):  
Oil And Gas ◽  
Facies Analysis ◽  
Pore Space ◽  
Sedimentary Cover ◽  
Clay Content ◽  
Geological Structure ◽  
Space Structure ◽  
Reservoir Properties ◽  
The Core ◽  
Promising Source

Aim. Due to the depletion of reserves of the main oil and gas complexes, the greatest interest is attributed to hard-to-recover reserves, complex-built objects of the sedimentary cover, the development of which was unprofitable until recently. One of these is the oil-bearing complex of the Achimov deposits of the Malobalykskoye field in Western Siberia. This article is devoted to the facies analysis and typification of reservoir rocks of the Achimov deposits in order to increase the reliability of determining the boundaries of the reservoirs, their interpretation and assessment of the petrophysical properties of the reservoirs. At the same time, special attention is paid to the facies analysis, which determines the characteristics of the reservoir. The Achimov deposits are a promising source of increasing resources and maintaining production at a high level. With their increasing importance, there are problems that complicate the search and assessment of deposits. Such problems include a high degree of reservoir compartmentalization, sharp facies variability, complex pore space structure, high clay content, low permeability values, etc. Materials and methods. The work is based on a comprehensive interpretation of the data of the lithological description of the core, the results of laboratory studies of the core and well logging data analysis of the Achimov deposits of the Malobalykskoye field. The methods used in the interpretation of GIS data, statistical analysis, comparison. Due to the fact that the reservoir properties of sand bodies are determined by the peculiarities of their formation in different conditions of sedimentation, it is necessary to establish a relationship between the petrophysical characteristics of rocks and their facies nature by substantiating petrofacies models. The use of the latter in geological modeling makes it possible to more effectively predict the reservoir properties (reservoir properties) of various facies lithotypes. Results. The paper presents the results of facies analysis and typification of the reservoirs of the Achimov deposits of the Malobalykskoye field, on the basis of which the boundaries of the reservoirs and the effective oilsaturated thicknesses were refined. Conclusions. Based on the results of the study, it can be concluded that it is necessary to develop refined petrophysical models for reservoirs with complex geological structure that take into account the facies features of rocks.

Palladium minerals from the Cauê iron mine, Itabira District, Minas Gerais, Brazil

1995 ◽  
Vol 59 (396) ◽  
pp. 455-463 ◽  
Author(s):  
Gema Ribeiro Olivo ◽  
Michel Gauthier
Keyword(s):  
Copper Oxide ◽  
Lake Superior ◽  
Minas Gerais ◽  
Iron Formation ◽  
Chloride Complexes ◽  
Mylonitic Foliation ◽  
The Core ◽  
Physico Chemical ◽  
Iron Mine ◽  
Chemical Conditions

AbstractPalladium-bearing minerals from the Cauê iron mine, Itabira District, Minas Gerais, Brazil, are found in gold-rich jacutinga, a hydrothermally-altered Lake Superior-type carbonate-bearing oxide facies iron-formation. Palladium occurs as: native palladium with trace contents of Au, Fe and Cu; palladseite ((Pd,Cu,Hg)17Se15), which was found in the core of a grain of palladium; palladium–copper oxide ((Pd,Cu)O); and arsenopalladinite (Pd8(As,Sb)3), with inclusions of palladium–copper oxide. The palladium and palladium–copper oxide grains are coated with films of gold and commonly do not exceed 100 µm in width. These palladium minerals occur in hematite bands and in boudinaged bands of quartz and white phyllosilicate parallel to the S1 mylonitic foliation. Palladium-copper oxide also occurs as inclusions in gold grains which are strongly to weakly stretched parallel to S1.Palladium mineralization is interpreted as synchronous with intense D1 shearing and contemporaneous with the peak of thermal metamorphism. At high oxygen fugacities and high temperatures (up to 600°C), Pd may have been transported as chloride complexes and deposited following changes in pH caused by mineralizing fluids reacting with jacutinga. Deposition may also have been prompted by the formation of insoluble selenide and arsenide–antimonide minerals and by the dilution of C1 concentrations in the mineralizing fluid. Textural studies, and the zonation observed in palladium and other hydrothermal minerals, suggest that oscillations in the physico-chemical conditions of hydrothermal fluids occurred during the mineralizing event.

scholarly journals The Core Structure and the Mobility of Dislocations in Ice

1978 ◽  
Vol 21 (85) ◽  
pp. 341-359 ◽  
Author(s):  
R. W. Whitworth
Keyword(s):  
Alternative Model ◽  
Dislocation Core ◽  
Dislocation Mobility ◽  
Atomic Processes ◽  
The Core ◽  
A Value ◽  
Normal Lattice ◽  
Crystalline Core ◽  
Dislocation Movement ◽  
Proton Disorder

AbstractThe evidence concerning the velocity of glide of dislocations on the (0001) plane of ice Ih is reviewed and related to atomic processes occurring within or near the dislocation core. The velocity is directly proportional to stress at low stress, with a value of the order of 500 Burgers vectors per second at — 18°C and a stress of 105 N m-2. The usual idea of a dislocation core is that it is “crystalline” in the sense that the linkages between molecules are as far as possible the same as those in the normal lattice. For such a model the disorder of protons presents an obstacle to dislocation movement, and recent theories predict that dislocations should not be able to glide as fast as they are observed to do. Various ways of avoiding this difficulty within the context of a crystalline core are discussed, but none seems likely to be successful. An alternative model is that the core is “non-crystalline”, with a disordered arrangement of mobile molecules within it. The movement of such dislocations should not be seriously impeded by proton disorder. Dislocation mobility would then be limited at least in part by anelastic loss due to the stress-induced order of protons in the surrounding lattice.

scholarly journals Newly Discovered and Exceptional Circumstances in Criminal Procedure of Some European States

2021 ◽  
Vol 4 (2) ◽  
pp. 44-66
Keyword(s):  
Criminal Procedure ◽  
European Countries ◽  
Court Decisions ◽  
Criminal Proceedings ◽  
Theoretical Justification ◽  
The Core ◽  
Legal Nature ◽  
Criminal Procedure Law ◽  
Principal Directions ◽  
Criminal Legislation

The article analyses the core and contents of the proceedings based on newly discovered or exceptional circumstances (hereinafter – PBNDEC) in the criminal procedure law of Ukraine and other European countries. The authors emphasize that the PBNDEC are not designed to eliminate shortcomings of the pre-trial investigation and the trial in criminal proceedings, providing the reserve function in discovering and correcting court errors, but rather serves its own purpose in the mechanism of legal defence. The order the criminal procedure activity during this stage is largely determined by the grounds for its implementation – newly discovered or exceptional circumstances (hereinafter – NDEC). The differences between both groups of such circumstances are provided. Procedural features of the PBNDEC, which separate them from the proceedings on appeal and cassation, are singled out. The goals of this stage in the criminal proceedings are formulated, and the significance of this stage has been revealed. The need for improvement in the criminal procedure legislation of Ukraine which regulates the PBNDEC has been justified. The articles answer the questions of how efficient the regulation of the PBNDEC in the criminal procedure law of Ukraine is: whether the regulation is in agreement with the standards, whether it is established in the criminal procedure law of European countries, whether any doctrine positions regarding the core of such a stage in criminal proceedings require rethinking or additional theoretical justification, and which, of the normative regulations of such form of appeal and review of the court decisions, the principal directions for improvement are. In order to obtain answers to the aforementioned and other questions, the legal nature and the models of PBNDEC in the criminal legislation of European countries are considered in section two of the article. Section three depicts the procedural specifics of the PBNDEC in the criminal legislation of Ukraine. Section four describes the definition, shows the goals and significance, and introduces the structure of this stage in the criminal proceedings. Section five embraces the characteristics of features of NDEC in the criminal legislation of Ukraine. In section six the grounds for the PBNDEC in the criminal procedure law of Ukraine are analysed.

scholarly journals The recent stress state of Germany – results of a geomechanical–numerical 3D model

2021 ◽  
Vol 1 ◽  
pp. 163-164
Author(s):  
Steffen Ahlers ◽  
Andreas Henk ◽  
Tobias Hergert ◽  
Karsten Reiter ◽  
Birgit Müller ◽  
...  
Keyword(s):  
Stress State ◽  
Stress Field ◽  
Boundary Conditions ◽  
3D Model ◽  
Sedimentary Cover ◽  
Calibration Data ◽  
Orientation Data ◽  
Displacement Boundary ◽  
The Core ◽  
Continuous Description

Abstract. A decisive criterion for the selection and the long-term safety of a deep geological repository for high radioactive waste is the crustal stress state and its future changes. The basis of any prognosis is the recent crustal stress state, but the state of knowledge in Germany is quite low in this respect. There are stress orientation data provided by the World Stress Map (WSM, Heidbach et al., 2018) and stress magnitude data from a database (Morawietz et al., 2020) for Germany, both providing selective information on the recent stress field. However, these data are often incomplete, of low quality and spatially unevenly distributed. Therefore, a 3D continuous description is not possible with these data so far, at most for the orientation of the maximum horizontal stress (SHmax), but not for the most important magnitudes of the minimum (Shmin) and SHmax. In the course of the SpannEnD project, a geomechanical–numerical 3D model of Germany is created, with which a continuous description of the complete tensor of the recent stress field in Germany is possible. The model covers an area of 1250×1000 km2 from Poland in the east, to France in the west, from Italy in the south to Scandinavia in the north. The depth extent is 100 km. Even though the focus is primarily on Germany, the model area was chosen to be so wide to minimize boundary effects and for a simplified definition of the displacement boundary conditions, which are ideally oriented perpendicular or parallel to the orientation of SHmax. The model contains a total of 21 units: The upper part of the lithospheric mantle, the lower crust, four laterally overlapping units of the upper crust, and 14 stratigraphic units of the sedimentary cover. The stratigraphic subdivision of the sedimentary cover is only done in the core area of the model; because this area is the focus of our study, our calibration data are mainly from this region and well-resolved geometry data are available. Outside of the core area, the sediments are grouped into an undifferentiated unit. The units are parameterized with density and elastic material parameters (Poisson's ratio and Young's modulus). The model has a lateral resolution of 2.5×2.5 km2 and a vertical resolution of a maximum of 240 m; in total it includes 11.1 million hexahedral elements. The equilibrium of forces between body and surface forces is solved by finite element method. The model is calibrated with Shmin and SHmax magnitudes from the WSM and data from the stress magnitude database. First, an initial stress state is generated and in a second step displacement boundary conditions are defined at the model edges, which are adjusted until a best-fit to the calibration data is found. The results show good agreement with both the SHmax orientation data from the WSM and the magnitudes of the two principal horizontal stresses (Shmin and SHmax) from the magnitude database.

scholarly journals MAPEAMENTO GEOLÓGICO DA REGIÃO DA SERRA DOS TURVOS, CARATINGA (MG), SETOR SUL DO ORÓGENO ARAÇUAÍ

2012 ◽  
Author(s):  
Gláucia Queiroga ◽  
Tiago Novo ◽  
A. C. Pedrosa-Soares
Keyword(s):  
Sedimentary Cover ◽  
Granulite Facies ◽  
Geological Mapping ◽  
Iron Formation ◽  
High Grade ◽  
Crystalline Core ◽  
High Grade Metamorphism ◽  
Iron Formations ◽  
Araçuaí Orogen ◽  
Southern Section

A área de estudo situa-se na parte sul do núcleo cristalino do Orógeno Araçuaí, próximo à fronteira com o Orógeno Ribeira. A característica fundamental da região é a abundância de rochas de alto grau metamórfico, na transição de fácies anfibolito-granulito. Uma cobertura metassedimentar neoproterozóica é a unidade dominante e está representada por paragnaisse migmatítico, bandado, com intercalações de quartzito, formação ferrífera micácea e formação ferrífera maciça. Corpos de anfibolito, pegmatito e charnockito também ocorrem na área. A principal estrutura dúctil é a foliação (Sn) regional, paralela ao bandamento composicional do granada-biotita paragnaisse. Fraturas são abundantes no quartzito e formação ferrífera maciça. As formações ferríferas são ricas em magnetita e formam corpos lenticulares com espessura decamétrica a centimétrica, concordantes com o bandamento composicional do granada-biotita paragnaisse. Preliminarmente, interpreta-se a gênese dessas formações ferríferas como sedimentar, durante a deposição dos protolitos areno-pelíticos do paragnaisse.Palavras-chave: metamorfismo de alto grau, formação ferrífera, Orógeno Araçuaí. ABSTRACT: GEOLOGICAL MAPPING OF THE SERRA DOS TURVOS REGION, CARATINGA (MG), SOUTHERN SECTION OF THE ARAÇUAÍ OROGEN. The study area is located in the southern part of the crystalline core of the Araçuaí orogen, close to the boundary with the Ribeira orogen. The main feature of the region is the abundance of high-grade metamorphic rocks of the amphibolite-granulite facies transition. A Neoproterozoic sedimentary cover is the dominant unit in the area and consists of migmatitic banded paragneiss with intercalations of quartzite, mica-bearing iron formation and massive iron formation. Amphibolite, pegmatite and charnockite bodies are also found in the area. The main ductile structure is the regional foliation (Sn) which is parallel to the compositional banding of the garnet-biotite paragneiss. Fractures are abundant in the quartzite and massive iron formation. The iron formations form lenticular bodies ranging in thickness from centimeters to decameters, which are concordant to the banding and foliation of the garnet-biotite paragneiss. Accordingly to field data, a sedimentary genesis can be suggested for the iron formations.Keywords: high grade metamorphism, iron formation, Araçuaí Orogen

Electron Microscopical Morphology of Cytoplasmic Granules from Horse Eosinophil Leucocytes

1993 ◽  
Vol 48 (7-8) ◽  
pp. 669-672 ◽  
Author(s):  
J. C. Stockert ◽  
C. I. Trigoso ◽  
A. Tato ◽  
J. M. Ferrer
Keyword(s):  
Structural Features ◽  
Cytoplasmic Granules ◽  
Considerable Heterogeneity ◽  
The Core ◽  
Crystalline Core ◽  
Specific Granules ◽  
Electron Microscopical

The structure of specific granules from horse eosinophil leucocytes is still largely unknown. In this work, electron microscopical studies of horse eosinophils reveal that the large cytoplasmic granules contain an external membrane, a m atrix o f less density, and a dense (non crystalline) core. Round vacuolar inclusions of matrix materials were often observed within the cores. Horse eosinophil granules showed a considerable heterogeneity, and three morphological types could be identified according to structural features of the core and matrix.

scholarly journals Is the World-System Approach Just a Global Perspective? The Connection Between Global and Regional Developments in Pre-Industrial France

1995 ◽  
pp. 497-511
Author(s):  
Kees Terlouw
Keyword(s):  
System Approach ◽  
World System ◽  
Global Perspective ◽  
Specific Situation ◽  
Regional Structure ◽  
Stable Position ◽  
The Core ◽  
The World ◽  
Mode Of Transportation ◽  
Entire World

France is the only state who always belonged to the core of the world-system and never attained hegemony, nor declined into the semi-periphery. This paper focuses on the reasons for this relatively stable position in the pre-industrial world-system. Crucial is France's size and fragmented regional structure. These constraints prevented France from building on its favorable position at the inception of the world-system. France's development within the world-system was further retarded by the shift in the center of gravity and mode of transportation of the world-system. This interplay between general processes, at the level of the entire world-system, and the specific regional structure within France, demonstrates how the general processes of the world-system can be linked to the specific situation in a given country.

Tectonic implications of syn- and post-emplacement deformation of the Mount Stuart batholith for mid-Cretaceous orogenesis in the North Cascades

1992 ◽  
Vol 29 (3) ◽  
pp. 479-485 ◽  
Author(s):  
Robert B. Miller ◽  
Scott R. Paterson
Keyword(s):  
British Columbia ◽  
High Temperature ◽  
Main Part ◽  
North Cascades ◽  
Geochronological Data ◽  
The Core ◽  
The North ◽  
Crystalline Core ◽  
Thrust System ◽  
Unknown Period

The 93–96 Ma Mount Stuart batholith intruded across the boundary between the Northwest Cascades thrust system and the crystalline core of the North Cascades. Although previously considered posttectonic, the northeast margin of the Mount Stuart batholith and its wall rocks have been involved in syn- to post-emplacement, southwest-directed thrusting and folding, and west-northwest stretching. Contraction ended shortly after emplacement, as indicated by high-temperature recrystallization in thrust-related mylonites of the pluton and by geochronological data, whereas west-northwest stretching continued for an unknown period of time. This is the best documented mid-Cretaceous contractional belt in the main part of the crystalline core. The shortening direction and timing are identical to that of southwest-vergent thrusts in the offset continuation of the core in British Columbia. The contractional belt provides a link between thrusting in the Northwest Cascades thrust system and deformation in the crystalline core.

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