Search

Accurate prediction of the spatial distribution of subsurface permeability is a fundamental task in reservoir characterization and monitoring studies for hydrocarbon production and CO2 geologic storage. Predicting permeability over large areas is challenging, due to their high variability and spatial anisotropy. Common approaches for modeling permeability generally involve deterministic calculations from porosity using precalibrated rock-physics models (RPMs) or geostatistical cosimulation methods that reproduce observed experimental porosity-permeability relationships. Instead, we have predicted permeability from seismic data using an iterative geostatistical seismic inversion method that combines the advantages of rock-physics and geostatistical modeling methods. First, we simulate facies through 1D vertical Markov chain simulations. Then, permeability, porosity, and acoustic impedance are sequentially generated and conditioned to the previously simulated facies model. An RPM is used to evaluate the misfit between the permeability predictions obtained from geostatistical cosimulation at the well locations and well-log values computed from the acoustic impedance. The residuals of the misfit function are used as conditioning constraints in the stochastic update of the models in the subsequent iteration. The outcome of our methodology is a set of multiple geostatistical realizations of facies, permeability, porosity, and acoustic impedance conditioned to seismic data and constrained by an RPM. We first illustrate the method on a synthetic 1D example and compare it to a traditional geostatistical inversion approach. We then apply our inversion to a 3D real data set to assess the methodology performance with scarce conditioning data and in the presence of noise.

Understanding the thermal behavior of nonsteady state subsurface geosystems, when temperature changes over time, requires knowledge on the speed of heat propagation and, thus, of the rock's thermal diffusivity as essential thermo-physical parameter. Mixing models are commonly used to describe thermo-physical properties of polymineralic rocks. A thermal diffusivity-porosity relation is known from literature that incorporates common mixing models into the heat equation and properly works for unconsolidated, clastic clayey, and sandy marine sediments of high porosity (35%–80%). We have proofed the relation's applicability for consolidated, isotropic sedimentary rocks of low porosity (

Realizou-se um estudo observacional, descritivo e retrospectivo a fim de se detectar alguns pontos na viabilidade do cumprimento da legislação brasileira em vigor, Portaria 344/98. Para tanto, foi criado um banco de dados contendo informações a respeito da prescrição ambulatorial em 4.405 receitas emitidas em cinco dias seguidos, durante o mês de novembro de 2002, nos diferentes setores do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo e dispensadas na Divisão de Farmácia do mesmo hospital. Os dados coletados de cada receita, foram usados para verificar a conformidade dos procedimentos relativos a referida portaria. Os resultados obtidos foram: as prescrições dos medicamentos não foram realizadas, na sua totalidade, de acordo com a denominação comum brasileira (DCB), o que vai contra os dispositivos da portaria; a prescrição de morfina foi muito baixa (0,25%), seguindo a tendência internacional; as prescrições de anorexígenos foram muito poucas (0,2% do total); com relação aos retinóicos, estes não foram prescritos; limitações das quantidades de medicamentos para tratamento de doenças crônicas e preenchimento incompleto das receitas foi também observado; a farmácia do Hospital das Clínicas cumpre os dispositivos legais da Portaria 344/98 diante de baixas não conformidades constatadas neste estudo e a dispensação de medicamentos na farmácia hospitalar do HC parece diferir de uma farmácia comercial. Brazilian legislation on prescriptions and dispensing of psychoactive drugs is enforced by \"Portaria 344/98\" enacted by \"Secretaria de Vigilância Sanitária\" - Ministry of Health as a result of the jointing of two former laws which were valid until 1998. Current legislation is quite complex and in many points does not contemplate some recommendations of international conventions. Professionals taking part in psychoactive-drug dispensing when not familiar with the legislation can bring difficulties to accomplish its determinations. The aim of this observational, descriptive, retrospective five-day survey was to detect points of vulnerability of the current legislation, as far as the documents for dispensing controlled drugs are concerned in a major university hospital in the city of São Paulo, Brazil. Database constructed with information about prescriptions and clinical dispensing of controlled drugs was used to verify the conformity of procedures related to \"Portaria 344\". The obtained results were as follows: Brazilian designation for drugs applied to public hospitals was not fully used; only 0.25% of prescriptions involved opiates like morphine followed the international tendency; anoretic and retinoid drugs were practically not prescribed; limitations in quantity of drugs prescribed for chronic diseases as well as incomplete prescriptions make out were also detected; the hospital pharmacy of College of Medicine of University of São Paulo has satisfied the legal requisites of \"Portaria 344/98\" once low compliance during the execution of this study has been noticed; all psychoactive dispensing in hospital pharmacies seems to be quite different from dispensing in commercial drugs.

Lake Garda, the largest lake in Italy at the southern front of the central Alps, provides a unique opportunity to reconstruct Quaternary geological processes related to the interplay between deglaciation driven sedimentation and tectonic activity. In fact, the topographic depression presently occupied by the lake was site of a major glacial tongue during the LGM, and is located close to the epicentral areas of two of the largest magnitude historical earthquakes recorded in the Po Plain, the Verona (Jan. 13, 1117) and Brescia, (Dec. 25, 1222) seismic events, characterized by Io IX-X MCS, respectively. Despite this peculiarity, geophysical surveys of the lake are scant. We present results of a waterborne geophysical survey of Lake Garda, leading to the acquisition of a densely-spaced grid of high-resolution seismic reflection profiles which image the lake floor and uppermost sedimentary sequence. These data enabled us to compile thematic maps which provide insights on active geologic processes in different sectors of the basin. We focused our work on a prominent seismic reflector (H1), correlated over the entire lake surface, to estimate the sediment deposition rate at the scale of the last 10 ka, and to evaluate the variability of seismic facies and geological processes in different sectors of the basin. Based on available stratigraphic data, we discuss whether H1 could mark the diachronic glacial/fluvio-glacial transition after the Last Glacial Maximum, when the ice tongues south of the Alps started to melt and collapse. We observed that sediments of the southern Lake Garda are affected by incipient tectonic deformation, and two major seismoturbidite-homogenite beds might represent over 50% of the Holocene sedimentary record in the lake depocenter, making the study of the Lake Garda stratigraphy an interesting tool for assessing earthquake hazards at the southern front of the Alpine chain.