Characterization of clastic sedimentary enviroments by clustering algorithm and several statistical approaches — case study, Sava Depression in Northern Croatia

Abstract This study demonstrates a method to identify and characterize some facies of turbiditic depositional environments. The study area is a hydrocarbon field in the Sava Depression (Northern Croatia). Its Upper Miocene reservoirs have been proved to represent a lacustrine turbidite system. In the workflow, first an unsupervised neural network was applied as clustering method for two sandstone reservoirs. The elements of the input vectors were the basic petrophysical parameters. In the second step autocorrelation surfaces were used to reveal the hidden anisotropy of the grid. This anisotropy is supposed to identify the main continuity directions in the geometrical analyses of sandstone bodies. Finally, in the description of clusters several parametric and nonparametric statistics were used to characterize the identified facies. Obtained results correspond to the previously published interpretation of those reservoir facies

EuS THIN FILM PROPERTIES IN RELATION TO STOICHIOMETRY AND DEFECTS

Par évaporation de EuS, on a condensé des couches minces polycristallines de EuxSy sur des substrats de verre de quartz à des températures comprises entre 20 K et 1400 K. La composition atomique, y/x, de ces couches minces varie de 0,8 à 1,2. Les changements systématiques observés à la température de Curie, la magnétisation, le champ coercitif, la mobilité des parois et la résistance électrique sont discutés en relation avec les changements mesurés dans la composition chimique (stoechiométrie) et avec les différences dans la concentration des défauts de structure.Polycrystalline EuxSy films with atomic ratios, x/y, ranging between 0.8 and 1.2 have been prepared by vacuum evaporation of EuS on to quartz glass substrates at temperatures ranging between 20 K and 1400 K. The systematic changes observed for the Curie temperature, the magnetization, the coercive field strength, the wall mobility, and the electrical resistivity have been related to the measured changes in chemical composition (stoichiometry) and to differences in the concentration of structural defects

The EU Geocapacity Project—Saline aquifers storage capacity in Group South countries

AbstractThe EU Geocapacity Project aims to obtain an estimation of the potential capacity of CO2 storage in deep saline aquifers, depleted hydrocarbon fields and coal beds in Europe. Prior to this project, the availability of data to calculate the storage capacity differed very much in each country. Some of them have already provided estimations for CO2 storage capacities in the framework of previous projects (e.g. GESTCO (FP5) and CASTOR (FP6)), while other countries have not been evaluated at all. Therefore, an important part of the work performed in the frame of the GeoCapacity project has been to homogenise estimation methodologies and reliability of data. Emphasis has been placed on the study of saline aquifers, as this type of geological formation, was until now, the less studied and most poorly understood compared to the depleted oil and gas fields. The work activities were organized in geographical groups to make them easier to manage.The Group South is composed of four Mediterranean countries: Spain, Italy, Slovenia and Croatia plus Bosnia–Herzegovina. Specific methodologies were adopted in order to achieve different goals: •Creation of maps of regional storage potential•Collection of geological information of storage sites•Estimation of storage capacities•Elaboration of databases to be inserted into GIS•Detailed analysis of case studies and scenarios for economic evaluation•Integration of the storage capacity data with emission sources and pipeline infrastructure Each of the countries belonging to Group South worked and continue to work in order to achieve such goals, despite of their different geological settings. The initial phase of such analyses included mapping of regional aquifers and locations of possible storages and seals described using data from hydrocarbon or water exploration, represented by borehole data and seismic surveys. Later on, structures contained in these aquifers were studied and CO2 storage capacity estimated with a higher precision. The two most promising or best defined structures in every country have been selected for a more detailed study.As a result of this project, it can be observed that CCS can play an important role in Mediterranean countries, as part of their strategy to mitigate GHG emission. Storage efficiency factor determination is the key issue, and also further exploration for new data