The Vaca Muerta shale has been developed for oil and gas production since 2010 and to date nearly 500 wells have been drilled. The large amount of static and dynamic information from these wells has enabled fracture design and production strategy optimization. This paper details the methodology used to integrate all available data in 3D models, in order to understand the impact of rock properties in the production. The model was simulated using a commercial reservoir simulator, showing that hydraulic fractures are acting as a dual porosity system with a large conductivity (~10 D) connecting a low permeability matrix (~100 nD). We studied multiple wells in the history match (HM), using separator pressure and choke size as the control variables for the wells, and rates and pressures as comparison variables. A multi-segmented well approach was used to describe the pressure drop inside the well, and a vertical lift performance (VLP) table to describe the flow from the tubing all along to the separator including the wellhead choke. The static model included the seismic interpretation, stratigraphic framework, geomechanical and petrophysical characterization. Rock permeability, initial pore pressure and total fracture pore volume were calibrated with field measurements used as constraints in the HM process. Fracture conductivity degradation was introduced in the model to explain observed changes in the wells productivity. Laboratory tests are being designed to validate these hypotheses. We established early in the project that individual well HM were not unique. It was only through the HM of multiple wells that we were able to reduce the range of uncertainties affecting well performance (matrix permeability, initial water saturation and fracture height). This has given us a more reliable tool to obtain ultimate recovery estimation ranges. The described model showed a good prediction of a well with water lift problems, giving an accurate forecast for the incremental gas rate after a tubing diameter change. We concluded that the multi-segmented well model is a good representation of the water hold-up fraction behavior. This methodology enables us to integrate all the knowledge of the subsurface into a model that can be run in short simulation time (~30 minutes), allowing us to iterate quickly during the HM process. The model can be run for single wells or multiple wells and is flexible to adapt for new areas. We plan to use this methodology to design and monitor pilots in new blocks and to evaluate different development plans for existing projects.

A number of fields in the Neuquén Basin are currently mature waterfloods. To obtain significant incremental volumes of additional oil, EOR technologies need to be screened and then implemented. Señal Picada is one of Argentina's largest fields with nearly 500 wells in 2013. These wells have exploited all the oil bearing areas of the field and have identified all of the oil water contacts in the various reservoir that make up this field. In 2013 the field was producing with a 96% water cut. Therefore for this field to have a long term future, post waterflood opportunities need to be identified. To accelerate the characterization of such a large field, it was decided to study a sector of the field which was thought to be suitable for an EOR pilot and where an excellent quality core has been acquired. By focusing on a sector, the construction and data QC of both the static and dynamic models was faster than if an attempt was made to construct a full field model. Additionally more iterations between static and dynamic models were possible in less time to identify which variables had the greatest impact on the history matching process and forecasts. With the main reservoir layers characterized, it was possible to both extrapolate the learning to the whole field and to evaluate EOR processes in more detail. The sector modeling demonstrated that 3–4 stratigraphic cycles had the highest potential for EOR. However within these cycles two very different facies were identified by the study, a high permeability sandstone suitable for EOR and a low permeability carbonate which would negatively impact any chemical injection program. The dynamic modeling of the field combined with analysis of the logs of infill wells surprisingly demonstrated that there was significant attic oil potential. This was interpreted as being due to the high vertical permeability in the field resulting in a waterflood which was more affected by gravity forces than viscous forces. In conclusion the sector modeling study characterized the reservoir, identified the key sands with potential for exploitation by EOR and that there was remaining oil to be recovered both by the reduction of the residual oil saturation to water or by improving the vertical sweep efficiency.

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Habitualmente, en los cursos de Electricidad y Magnetismo, el cálculo del campo magnético generado por una bobina de sección circular es abordado usando muchas pero no especificadas aproximaciones, tanto desde la Ley de Biot y Savart como desde la Ley de Ampère (considerando materiales lineales). En el primer caso se considera un modelo de solenoide finito o infinito como superposición de "muchas" espiras y se usa el resultado del campo generado en el eje para una espira circular por la que circula corriente. De este modelo se obtiene un resultado para la determinación del campo magnético en el eje del solenoide que se supone también válido para todo punto dentro del mismo despreciando efectos de borde. En el segundo, se supone que el solenoide es infinito o que se desprecian efectos de borde y se acepta como "acto de fe" que el campo fuera del solenoide puede considerarse nulo. En este trabajo, realizado entre docentes y alumnos ya formados, proponemos una manera poco usual de abordar la

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