A method is presented that integrates a triple porosity model with sonic, density and resistivity logs for evaluation of tight gas formations. The interpretation takes into account results from petrographic work in the Western Canada Sedimentary Basin (WCSB), which indicates that tight rocks are comprised of different types of pores including (i) intergranular, (ii) slot + microfractures, and (iii) isolated non-effective porosities. Seismic data are powerful in the exploration and production domains but a method that integrates seismic velocities and the observed triple porosity petrographic characteristics of tight gas formations is not available. This paper provides the theoretical foundation and development of equations for this integration along with examples using real data from tight gas formations in the WCSB. The proposed method provides estimates of inter-well formation resistivity, porosity and water saturation to obtain estimates of original gas in place. The comparison between resistivity from seismic velocities and resistivity from well logs is good with a strong statistical effectiveness. Under favorable conditions, the partition between effective and non-effective porosity might be estimated. The proposed methodology has significant potential for application in tight gas formations of the WCSB. The method can probably be extended to other regions around the world, which possess tight gas formations with similar characteristics to the ones described in this work.

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A post stack seismic inversion has been applied to 2D and 3D seismic data in order to obtain a quantitative assessment of rock properties including density, compressional velocities and porosity in a tight gas sandstone. To achieve this objective, the study develops a new relationship between Acoustic Impedance (AI) and porosity.This study focuses on a post stack seismic inversion through a band limit technique that involves three major steps: 1) Derive a low frequency velocity model using sonic logs, 2) Invert the seismic traces using a recursive inversion procedure giving as a result the middle frequency model band of the AI, and 3) Combine the previous models in order to obtain the full band limit inversion product.The methodology is demonstrated using data from a tight gas reservoir formation chracterized with low porosity and permeability located at approximately 2, 000 meters (TVDSS) in the study area. From the model inversion, the acoustic impedance (AI) is compared with variations in porosity resulting in a reasonable correlation for the stratigraphic interval studied.The methodology can probably be extended to other regions around the world, which possess tight gas formations with similar characteristics to the ones described in this work.

Two phase flow occurs in many applications in industry, mainly in the transport of mixtures in pipes. The identification of these patterns is of fundamental importance in the design of piping systems and equipments. In this scenario, this work proposes an experimental study to identify multiphase flow patterns of water and air in horizontal tubes. The study was developed using an experimental circuit of 26 mm diameter and 9.2 m length pipe, at Thermal Sciences Lab at Federal Technological University of Paraná. To characterize the parameters one used an intrusive mesh electrodes sensor, a tomographic technique that allows details of the distribution of phases with good temporal and special resolution. Tests were conducted using several experimental settings of water and gas superficial flows, mostly with slug flow characteristics. Measurements were compared to models and the temporal void fraction series were analyzed to produce bubble velocity and frequency information, showing the characteristics for each two-phase pattern.

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