bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy Efficiency Scenarios Following the Energy Trilemma - Argentina's Commitment to COP21
Authors: Cervantes-Bravo R.J. , Ñaupari-Barzol H. , Jimenez-Nieves E.T. , Magnelli D. , Dabrowski A. 
Published: May 2017

Abstract
Energy efficiency in the framework of the energy trilemma will guide to energetic policies focused on economic growth and development of the Developing Countries. Many of the International Organizations: such as the International Energy Agency (IEA) agreed to promote the rational use of the expressed sources in reducing energy intensity to mitigate accelerated climate change through the reduction of CO2 emissions as agreed at COP21 in Paris.
The transition from Oil to Natural Gas in Argentina was marked in the years 1994 - 1999, because of an intense productive activity, causing an exponential increase in consumption. Although, if the Natural Gas less pollutant than oil, currently, the change in the matrix, did not report a reduction of C02 as expected due to the lack of technology and the rational use of these sources as energy. This implied that currently, the share of fossil fuels in the energy matrix more than 84 % above dealer, with nearly 51.1 % of Natural Gas.
Therefore, the study focuses on the energy security of Argentina's growing energy demand and environmental Commitments; through, increased energy efficiency with the assumptions in reducing Energy Intensity towards a more sustainable energy trilemma to the medium and long term. It is worth mentioning that the reduction of the total demand of a country is associated with levels of energy efficiency. In our case, by 2035 an increase in energy efficiency of 19% could we reduce demand 36%; that is, a reduction in energy intensity of 29 % compared to 2015.
The scenarios with reduction in energy intensity by 2035 are 1 %, 1.5 % and 2 % annually, which will involve a reduction in the consumption of primary sources and consequently a reduction in CO2 emissions of 5.3%, 14.4% and 20.2% respectively in each case. In this way, we could diversify the energy matrix progressively, towards more sustainable developments.
To project the demand for primary sources from 2015 to 2035, it is necessary to design a macro-econometric model, based on an annual GDP growth of 2.77% and the projection of energy intensity according to 3 proposed scenarios. Then the relationship population country / world, will enable us to project the maximum allowable CO2 emissions by 2035, with a commitment not to increase the temperature more than 2 °C by 2100 and the commitment of Argentina with COP21 to reduce 15% CO2 emissions by 2030.
Finally, the overall objective of the research will be to adjust energy policies of the country in the medium and long term through of the Evolution of Energy Matrix Primary versus the Evolution of Energy Efficiency, under the precept of securing the demand and comply with COP 21 under a more sustainable energy trilemma.
Optimizing Well Spacing of Multi Fractured Tight Gas Wells in Argentina's Lajas Formation through High Resolution Simulation: Barrosa Norte Field Case Study
Authors: Francos J. P. , Wagner F. , Coppo R. , Santiago E. 
Published: May 2017

Abstract
The area denominated Barrosa Norte, located in the south of Los Barreales and Mari Menuco Lakes (Neuquén Province, Argentina), is the most important Tight Gas development of YPF along with Sierra Barrosa and Aguada Toledo anticlines. Gas production from the unconventional Lajas Tight Gas formation in Barrosa Norte field is increasing as a result of an intense exploitation strategy since its discovery in 2014. Although multi fractured wells have already demonstrated the potential of the Lajas formation in the Neuquén Basin, optimization is still ongoing to determine the optimum well spacing.
The objectives of this paper are:
– To describe the methodology used to build a high resolution numerical model that represents the multi fractured wells in Barrosa Norte field – To present the results of an uncertainty and optimization study that narrows the range of the different uncertainty parameters defined – To describe and to present the infill development strategies evaluated and the optimum well spacing defined for the Barrosa Norte field
A high resolution simulator and a complex automatic workflow in a pre/post processor were used to achieve a history matching of observed production and pressure data of Barrosa Norte wells at well level and at hydraulic fracture level. This was achieved after an uncertainty analysis, which narrowed the range of uncertainty of different parameters, and after the application of optimization algorithms.
The multi fractured wells were modelled through a novel LGR approach to take into consideration the tilt of the reservoir. Several combinations of parameter values were obtained that satisfied the history match, resulting in a range of solutions. Finally, different infill development strategies were evaluated until the optimum well spacing was achieved.
The traditional LGR method for modelling hydraulic fractures is not best applicable in tilted reservoirs. Therefore an extension of the LGR method was developed proving to better characterize hydraulic fractures. The development of an automatic workflow in a pre/post processor proved to be a key tool for assisted history matching. On top of this, the use of uncertainty and optimization algorithms accelerated the achievement of results.
Use of Interference Tests to Constrain the Spacing of Hydraulically Fractured Wells in Neuquen Shale Oil Reservoirs
Authors: Chen T. , Salas-Porras R. , Mao D. , Jain V. , Thomas M. A. , Kruijs E. , Huckabee P. T. , Stephenson B. J. , Scholten S. O. 
Published: May 2017

Abstract
Well spacing is a key factor in the evaluation of pad economics for hydraulically fractured horizontal wells. The drilling at the wrong well spacing leads to either over-capitalization risk or leaving reserves in the ground both resulting in loss of net present value risk. This paper presents data acquisition techniques that aid in well interference identification and quantification. Integrated analysis of data from a well pad in the Vaca Muerta formation, including microseismic, chemical tracers, geochemical fingerprinting, and pressure measurement, indicates both pressure and production communication between the two wells studied. Then a dedicated interference test is designed and analyzed to provide insights on well spacing. The test consists of alternating shut-in periods of the two wells during which pressure and rate are closely monitored. Analytical and modeling work has quantified the degree of interference to be up to 20% on production rates. This interference test is performed between two ‘semi-confined’ wells. Future multi-well pads are planned to understand the production potential of a fully ‘confined’ well and the interference between neighboring wells, to further understand the well spacing and pad economics.
Historical Production Analysis of VacaMuerta Formation in the Neuquén Basin: A Guide to Understand the Past, Present and Future
Authors: Tagarot-Seadi G. , Vicente M. , Luongo S. A. 
Published: May 2017

Abstract
In this study, the historical production of VacaMuertais evaluated aiming to capture the complexities of this formation in terms of fluids production and recovery performance. This paper integrates the Neuquén province production analysis with the objective to understand the oil and gas historical production behavior in a development area of roughly 12,000 sq mi (31,000 km2).A comprehensive evaluation using public data was conducted to present the contribution and the impact of VacaMuerta oil and gas production on the region and the country.
The VacaMuerta formation represents the most-challenging source of new oil and gas in Argentina, with a huge potential considering the size of the development area in any block across the basin, the reservoir gross thickness and the resulting fluids in place, and the way forward to be achieved regarding the balance between well cost reduction and productivity improvement. There have been important drilling and development efforts in the last 4 years in which both vertical and horizontal wellbore configurations have been implementedand tested over the longterm. However, there are still uncertain factors under evaluation to assess the VacaMuerta formation performance, which achieved 29 million barrels and 124Bcf in December 2016, with 674 oil and gas producer wells.
The workflow focuses on the analysis of historical production for both vertical and horizontal wells, average rates and cumulative production of initial 6 and 12 months, water cut and gas-oil ratio (GOR), decline analysis and vintage performance, with the addition of heterogeneity index plots. Production history statistics and probabilistic analysis were incorporated in the study to summarize and present the evaluation results. Important aspects related to well decline behavior and estimated recovery for the initial years were also analyzed.
In this paper, we present the main findings and results of a complete production analysis of VacaMuerta formation after more than 10 years of production. This paper provides an overview of the historical production performance and the key elements for production forecasting. The integration of this production information with geology, reservoir characterization, well design, and completion and operation strategies provides an essential reference to improve the understanding of the production potential and the visualization and ranking of any well, field, or area in the Neuquén basin.
First Project of Auto-injection in Patagonia Argentina
Authors: Bogan F. , Ordoñez M. N. , Pyczil D. , Salvarredy Aranguren M. , Verde R. 
Published: May 2017

Abstract
This contribution presents the concept of auto-injection with mechanical pump, as an alternative to the initial stage of a waterflooding project without the prior need of building a water treatment and injection pilot plant, aqueducts and injection lines (facilities). This case of study shares the results of this technique applied for first time in the development of a marginal oil field called Cerro Piedra, operated by YPF on the western flank of San Jorge Gulf basin (Patagonia, Argentina).
The auto-injector, unlike a multilayer conventional injector, is self-sufficient and simple injection. It produces and injects briny water in the same wellbore; it is not required to invest on facilities to evaluate waterflooding response. Moreover, it forwards the start of injection and consequently quickens the reservoir's response improving project's profitability.
The fluid enters to the mechanism's circuit by a crossflow piece, where a hollow mechanical pump, driven by an individual pumping unit and hollow rods (4,600 ft maximum depth), produces up to 700 STB/D of water to the wellhead and pressurizes it up to 2,000 psia. At the surface, a measuring bridge registers flow, pressure and temperature. Finally, the pressurized fluid reenters to the well by the annular tubular-rod and passes through the crossflow piece to the injection zone.
The oil field is located 75 miles far away from Las Heras (Santa Cruz, Patagonia Argentina) and 40 miles from the nearest water treatment plant. The San Jorge Gulf basin is filled by a sequence of fluvial sediments which generate thin and low areal extent multilayer reservoirs. Bajo Barreal sedimentary unit is characterized from top to bottom by: briny water levels (3,500-8,000 ppm) to oil productive levels reservoirs. This distribution allows the auto-injector to produce shallow briny water layers and inject it into deeper hydrocarbon reservoirs.
The project includes an initial pilot phase to evaluate the waterflooding response, established with five auto-injectors; an intermediate stage of full development, developed by the completion of the water treatment and injection plant and conversion of eight selective injectors; and a final conversion phase, where the auto-injectors are reconverted to traditional injectors.
This auto-injection strategy allows us to evaluate the waterflooding response in a marginal virgin zone, without needing to build facilities for water treatment. Therefore it gives a sustainable water management of the field. This alternative approach improves at least 2% of original project's profitability, which was planned with the construction of an injection pilot plant.
Automated MPD System in Offshore Gulf of Mexico Further Substantiates Value of Drilling Technique in High-Pressure Zones
Authors: Barbosa Alberto , Gallego Gilbert , Clemente Fabricio , Padilla Rivelino , Mondragón Gabriel Enrique , Balderas Jose Antonio 
Published: May 2017

Abstract
This paper presents a case history that demonstrates the benefits of drilling using automated managed pressure drilling (MPD) technology rather than conventional equipment. Primary factors for the comparison include drilling time, volume of fluid losses to the formation, and performance drilling statistics.
Automated MPD technology provided a non-conventional approach to achieve the main objective during this project. The goal was to reach the planned total depth (TD) in the 8 1/2-in. well section that has a high-pressure zone while reducing pressure-related nonproductive time (NPT). An automatic monitoring and reaction system was used to identify and control undesirable events—such as influxes, losses, ballooning, or all of the above—even when there was no longer a visible operational drilling window available (judging from the pore pressure, collapse pressure, and fracture pressure). Using the automatic MPD system enabled the driller to exercise precise control over bottomhole pressure (BHP) during the entire drilling process, to locate the perfect balance point, to minimize fluid losses and potential influxes, and to drastically reduce NPT.
Shale Reservoir Characterization Using LWD Azimuthal Sonic and Advanced Gas Detection
Authors: Mejia C. , Crosby Z. , Barnett C. , Heard S. , Llanos D. , Marchal D. , Porras J. 
Published: May 2017

Abstract
Unconventional reservoirs such as the Vaca Muerta formation in Argentina continue to be an important source of oil and gas, and represent a vital source of energy for specific segments of the global market. Achieving technical and financial objectives when developing such reservoirs requires operators to manage operational costs while still obtaining sufficient geological, petrophysical, and geomechanical information to successfully evaluate and develop the reservoir. In a recent Vaca Muerta exploration well, LWD resistivity and azimuthal sonic measurements were combined with advanced mud gas analysis of C1 to C8, toluene, and benzene gas components. These two data sources, acquired while drilling, were used in an integrated petrophysical analysis which characterized the stratigraphic variation of key reservoir parameters and geomechanical properties to identify sweet spots for further horizontal well development.
Geomechanical analysis from azimuthally oriented LWD slowness measurements revealed stressinduced anisotropy by identifying the splitting of shear slowness around the wellbore. The comparison with wireline sonic and micro-imaging tools in the same well confirmed the relatively isotropic acoustic response (2-3 % anisotropy) in the upper section and a more anisotropic acoustic response (7-9 % anisotropy) in the lower section of the Vaca Muerta. Additional mechanical properties such as elastic moduli were calculated to evaluate fracability, and the unconfined compressive strength (UCS) was correlated to the mechanical specific energy (MSE) from drilling mechanics measurements to monitor drilling efficiency.
Mud gas ratio analysis revealed variations in reservoir thermal maturity, identifying wet gas and dry gas intervals, while LWD resistivity and sonic data were used to compute TOC (using the Passey overlay method), porosity, and water saturation. The key reservoir quality parameters (TOC, porosity, water saturation, thermal maturity, and clay volume) were then combined with geomechanical properties (Poisson’s ratio, Young’s modulus, and UCS).The resulting interpretation provided a continuous evaluation of the entire Vaca Muerta sequence, facilitating zonation and selection of potential landing points for horizontal development wells.
This comprehensive evaluation from the integration of the LWD azimuthal sonic and advanced mud gas analysis demonstrated a cost-effective solution to characterize the formation which enhances real-time decision making, and provides the basis for optimizing well placement and completion strategies in the Vaca Muerta formation.
Detailed Modeling of Carbonate Acidizing by Coupling a Multi-Purpose Pore-Network Simulator to the Chemistry Package PHREEQC - Application to Chelating Agents
Authors: Ameri A. , Raoof A. , Blonk N. C. , Cnudde V. 
Published: May 2017

Abstract
In this study, an effective method is developed to couple the multi-directional pore-network (MDPN) model, called PoreFlow, with the chemistry simulator PHREEQC in order to simulate the reactive flow of chelating agents into carbonate media. A novel method based on solving a 1D chemical reactions and projecting the chemistry in the 3D pore scale flow field is developed, which significantly increased the computational efficiency. Results from several simulations are presented to demonstrate the capability of PoreFlow and the developed method to mimic reactive transport of chelating agents in porous media. It is also shown that the interactions between chelating agents and carbonate rocks can be accurately modeled by implementing the proper multi-step protonation kinetic of chelating agents versus pH. The developed model is capable of computing the change in porosity and the 3D flow field due to calcite dissolution by the progress of chemical reactions. In addition, the evolving flow model provides the corresponding relationship between porosity and permeability for a specific porous media. The model successfully reproduced the experimentally observed permeability changes due to the creation of wormholes at various acid flow rates. The results are validated by comparing the simulation outputs to the micro-CT images taken from the samples after the chelating experiments. Moreover, it is shown that the average dissolution rate for heterogeneous carbonate rocks is not only governed by the pore-scale physical heterogeneities but also by the local chemical equilibrium and speciation of chelating agents at various pH values.
Prediction of PVT Properties in Crude Oil Using Machine Learning Techniques MLT
Authors: Ramirez A. M. , Valle G. A. , Romero F. , Jaimes M. 
Published: May 2017

Abstract
A new mathematical model is proposed using machine learning techniques for estimating PVT fluids properties such as bubble pressure and oil formation volume factor as a function of the solution gas-oil ratio, gas specific gravity, oil specific gravity, and temperature.
The result obtained with this new approach are compared with previous published correlations. The proposed method for PVT properties estimation consists of two stages: data decorrelation through Principal Component Analysis (PCA) and PVT properties estimation through an Artificial Neural Network (ANN). Data decorrelation is used to reduce redundancy in the data, which decrease the number of neurons and hidden layers needed for an ANN to achieve a high accuracy estimation. In the development of the proposed method there were used 504 points obtained from the literature as follows: 360 for training, 40 for cross-correlation and 104 for testing. The present model was compared with empirical correlations of PVT fluids properties in terms of absolute average percent error, standard deviation, and correlation coefficient; using worldwide experimental PVT data.
The results obtained show that the proposed model provides better estimation and higher accuracy than the published empirical correlations. The present model provides predictions of the bubble pressure and formation volume factor with a correlation coefficient approximately of 98%. Trend tests were performed to check the behavior of the predicted values of bubble pressure and formation volume factor for any change in reservoir temperature, solution gas-oil ratio, gas gravity and stock-tank oil gravity.
The model was based on artificial neural networks, and developed using 504 published data sets from the Middle East, Malaysia, and North Sea fields. This improvement in PVT calculation accuracy will be of invaluable support for simulations and designs applied in Oil industry.
Visualization of Opportunities through Quick Workflows and Methods for Reservoir Characterization and Correlation
Authors: Saccomano A. F. , Limeres A. C. 
Published: May 2017

Abstract
The purpose of this paper is to present some alternative workflows and methods that can be used for a quick initial reservoir characterization. We apply these methods in different fields to analyze stratigraphic correlation, sand distribution, and recovery opportunities.
We analized Spontaneus Potential (SP) and Resistivity (R) logs, the only two curves run in the wells of the old mature fields studied. We built envelope curves for them, which are moving window averages that capture SP or R values for shales and clean sands. These curves are applied to compute the shale volume (Vsh) as an automatic multiwell process that takes into account formation and well variations in a simple way. We compared this Vsh with a traditional petrophysiscal interpretation and showed good validation results in many oilfields. We used this Vsh to build a simple sand-shale log and then a 3D model, analyzing spatial trends and connected volumes, which helped visualize main production units and waterflooded intervals. By means of simple calculations, it is also possible to determine non perforated hydrocarbon-bearing sands, and obtain a list of workover opportunities in a quick way. Zones for a possible EOR project could also be determined.
Additionally, we computed a derivative for the base envelope curve of R, which shows large scale variations in rock properties. We find vertical patterns in wells that can be followed for long distances, showing great lateral continuity, and helping determine a stratigraphic correlation between different oilfields. Although it has low resolution, it captures the main stratigraphic features.
Lastly, we computed a probabilistic forecast in 3D for each fluid type observed at swabbing tests. This is a routine workflow based on nearby swabbing tests, and should be simply used as a quick guide.
The envelope curves proved to be useful for a quick log normalization, baseline shift correction, Vsh calculation, and regional trend analysis. All these approaches are very effective in big fields with hundreds of wells and multiple layered reservoirs due to the speedy methodology. They are useful in visualization stages as an initial project overview.