bluuebunny/crossref_metadata_2025_split huggingface dataset:
India Aims To Offset Production Declines, Slash Energy Imports
Authors: Henni Abdelghani 
Published: June 2016

Country Profile
With 17% of the global population, India faces a huge challenge to meet its growing domestic energy consumption, especially as it holds only 0.35% of oil reserves and 0.6% of natural gas reserves in the world.
As a result of dynamic economic growth, the country’s oil consumption is expected to increase from 3.7 million BOPD in 2013 to approximately 4.4 million BOPD by 2018.
According to the BP Statistical Review of World Energy 2014, India’s proved oil reserves stand at 5.7 billion bbl with a production of 894,000 BOPD. Ranked as the fourth largest oil consumer after China, United States, and Russia, the country imports 82% of oil and 25% of natural gas to meet its demand.
Approximately 56% of India’s reserves are offshore and 44% onshore. The majority of the reserves is located in the western offshore region, near Gujarat and Rajasthan. The Assam-Arakan basin in the northeastern region holds 23% of reserves and 12% of the production in the country.
Although the country has enormous production potential, exploration efforts have not yet tapped the Indian sedimentary basin. Data from the Directorate General of Hydrocarbons (DGH) showed that India has a sedimentary area of 3.14 million km2 consisting of 26 basins, of which 1.39 million km2 is onshore, 0.4 million km2 is located in shallow water, and 1.35 million km2 is located in deep water. Deepwater oil production began in September 2008 when Reliance Industries (RIL), India’s largest private sector company, started production in the KG-D6 block of the Krishna-Godavari basin in the eastern offshore region.
According to the state-controlled Oil and Natural Gas Corp. (ONGC), only 22% of the sedimentary area is well explored, 44% has had exploration initiated, 12% is poorly explored, and 22% is unexplored. Of the 26 basins, only seven are currently producing.
To boost investment in the upstream sector, Indian exploration and production (E&P) companies want the government to provide incentives to local players. “The core policy initiative of the government of India’s ‘Make in India’ can gain necessary momentum and direction if supplemented by ‘Discover in India’ initiative, the latter aimed at discovering, developing, and producing energy resources in India,” said Manish Maheshwari, chief executive officer of Essar Oil E&P.
Maheshwari said that policies with a clarity of intent and richness in content are needed to attract the much needed capital in the upstream E&P sector. “We expect the Ministry of Petroleum and Natural Gas to usher in the next wave of reforms in the E&P sector through various policy initiatives. For instance, exploration focus through open acreage licensing policy, execution driven through simultaneous exploration and production of reserves across conventional and unconventional plays, and ensuring fiscal certainty,” he said.
Technology Focus: Reservoir Simulation (July 2015)
Authors: Bailey William 
Published: June 2016

Technology Focus
Coupled, full-field, integrated, holistic, or asset: Call it what you will, this class of modeling is becoming increasingly commonplace. The ability to interrogate the response of a system, from the reservoir to fiscal meter, is quite potent and encourages integration in all senses of the word—technically, operationally, and organizationally. Such end-to-end models may reveal bottlenecks, constraints, and potential flow-assurance issues.
While the benefits are manifest, two related issues are worthy of consideration: complexity and piloting. The complexity of any individual component (such as the reservoir model) refers to the engineering judgment required to ensure that it is fit for purpose. For example, should one use a simple model (computationally rapid but approximate) or should a more complex model (computationally slower but accurate) be adopted? The former is better suited for rapid scenario screening and sensitivity analysis, while the latter is better suited for detailed engineering, with a spectrum of models in between.
Piloting is another consideration. The degree of technical insight required to competently steer any single component simulator is often quite high. Having several simulators under a single, seamless platform places an extra burden on the pilots involved because the added layer of software (the integration platform) may mask possible shortcomings in a model, thus rendering potentially incorrect results and even suboptimal capital decisions.
These considerations notwithstanding, I am genuinely optimistic about the potential these full-field models will bring and the insights they can deliver. More articles are certain to appear detailing predictions vs. observations and how planning, operations, and economics benefited from such integrated studies. I respectfully submit that the story of fully coupled, full-field, integrated asset modeling has only just begun. JPT
An Efficient Work Flow for Planning Well Completions and Forecasting Profitability
Authors: Carpenter Chris 
Published: June 2016

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 169821, “Well Completions and Profitability: A Horn River Shale Case Study,” by C.R. Ross, SPE, and D.M. Anderson, SPE, IHS; C.P. Stephens, SPE, Calfrac Well Services; and C. Virues, SPE, Nexen Energy, prepared for the 2014 SPE Hydrocarbon Economics and Evaluation Symposium, Houston, 19–20 May. The paper has not been peer reviewed.
The objective of this paper is to develop and demonstrate an efficient work flow that will help stakeholders make better decisions in the area of completion planning. The work flow uses information from fracture modeling, production-data analysis, and project economics to quantify the relationship between the key input parameters of the well completion (pumping rate, proppant, and fluid pumped) and expected profitability expressed in net-present-value (NPV) terms.
Introduction
Over the past decade, completion costs have risen because of longer laterals, higher pressures, and an increase in stages and in fluid and proppant pumped. As completion teams continue to see economic production from larger completions, it is safe to assume that the cost of completions will remain high relative to total well cost. While drilling costs are generally spread out over weeks or months, completion costs are highly concentrated at the end of the development phase. Furthermore, the risk of unforeseen costs in the completion phase creates significant uncertainty in profitability. This type of cash-flow profile (Fig. 1) causes the completion phase to largely determine the profitability of a well. It is difficult to separate the impact of completion and reservoir effects on production.
A quick review of the variation in completions used currently (provided in the complete paper) emphasizes that different strategies are needed to maximize profitability in different plays.
Summary of Work Flow
The purpose of this work flow is to evaluate the effectiveness and profitability of a completion for a well that has an established production history, with the intention of recommending improvements for future well completions. This work flow is best applied at an initial decision phase. Essentially, this work flow combines fracture modeling with production-data analysis—two independent techniques. Effective fracture height, length, and conductivity are key to linking the two methods.
Although a shale-gas case study is presented in the complete paper to illustrate the work flow, it is intended to be of use on any producing oil or gas well. The work flow should be thought of as a modular process into which analysis methods can be substituted as required.
Enhanced Gas Recovery by CO2 Sequestration vs. Refracturing Treatment
Authors: Carpenter Chris 
Published: June 2016

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 172083, “Enhanced Gas Recovery by Use of CO2 Sequestration vs. Refracturing Treatment in Unconventional Shale-Gas Reservoirs,” by Mohammad O. Eshkalak, SPE, Emad W. Al-Shalabi, SPE, Alireza Sanaei, SPE, Umut Aybar, SPE, and Kamy Sepehrnoori, SPE, The University of Texas at Austin, prepared for the 2014 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 10–13 November. The paper has not been peer reviewed.
In this paper, shale-gas-field data have been evaluated and incorporated in simulations for both carbon dioxide (CO2) enhanced-gas-recovery (EGR) and refracturing-treatment purposes. This comprehensive sensitivity study helps in understanding the key reservoir and fracture properties that affect production performance and EGR in shale-gas reservoirs. The findings of this study recommend initial hydraulic refracturing of shale reservoirs for enhancing gas production, followed by CO2 injection at a later time.
Introduction
In this paper, two different EGR methods are investigated and systematically compared in terms of efficiency. The first method is a refracturing treatment in order to revive a shale-gas well that has failed to achieve economic gas-production rates. The second proposed method is CO2 injection for both storage/ sequestration and EGR. Discussions and definitions of each of these methods, as well as governing equations, are provided in the complete paper.
Basic Reservoir Model With Multifractured Gas Wells
The numerical-simulation technique is a technology that enables characterization, development, and management of a producing reservoir. It integrates geologic, geochemical, and petrophysical properties and examines their effects on production. The ability to use simulation to investigate the sensitivity of production to various reservoir properties is critical for the decision-making process in unconventional shale formations. Fig. 1 shows the configuration of Wells UT-1 and UT-2 in the shale-reservoir model. As seen in Fig. 1b, in order to maximize methane-gas production by a refracturing treatment, the new fractures are placed in the middle of each primary fracture.
CO 2 Huff ’n’ Puff Scenario. In this scenario, after 5 years of production from both wells, one of the producers is converted into a CO2 injector for 5 years. Also, another 5 years is given as a soaking time. Afterward, wells are put back on production. Methane (CH4) recovery for this scenario is almost less than 4%. On the basis of the observed mass fraction of production after soaking time in the 15th year, it is observed that 96% of CO2 is produced back while only 4% of CH4 is produced at the well. This finding shows that the huff ’n’ puff process is not a viable option for CO2 EGR because it delays 5 years of profitable gas production. Hence, this scenario was excluded as an option for CO2 EGR, and, for the rest of the study, the authors compare CO2 flooding with refracturing treatment.
SERENDIPITOUS DISCOVERY OF A PROJECTED PAIR OF QSOs SEPARATED BY 4.5 arcsec ON THE SKY*
Authors: Heintz K. E. , Fynbo J. P. U. , Krogager J.-K. , Vestergaard M. , Møller P. , Arabsalmani M. , Geier S. , Noterdaeme P. , Ledoux C. , Saturni F. G. , Venemans B. 
Published: June 2016

ABSTRACT
We present the serendipitous discovery of a projected pair of quasi-stellar objects (QSOs) with an angular separation of Δθ = 4.50 arcsec. The redshifts of the two QSOs are widely different: one, our program target, is a QSO with a spectrum consistent with being a narrow line Seyfert 1 active galactic nucleus at z = 2.05. For this target we detect Lyα, C iv, and C iii]. The other QSO, which by chance was included on the spectroscopic slit, is a Type 1 QSO at a redshift of z = 1.68, for which we detect C iv, C iii], and Mg ii. We compare this system to previously detected projected QSO pairs and find that only about a dozen previously known pairs have smaller angular separation.
FINDING THE CENTER: AN ANALYSIS OF THE TILTED RING MODEL FITS TO THE INNER AND OUTER PARTS OF SIX DWARF GALAXIES
Authors: Boisvert John H. , Rhee George 
Published: June 2016

ABSTRACT
We present a study of the H i emission of six dwarf galaxies. Profiles of dark matter halos of galaxies such as these have been the subject of much debate. In this paper we investigate the accuracy with which the dynamical center (the center of rotation) of each galaxy can be determined. We have used the tilted ring model. We find that the tilted ring method produces plausible centers that are consistent with other published works that used rings at radii larger than 1 kpc. At a radius of 1 kpc the method often converges on centers that do not make sense, producing, for example, radial velocities for the galaxies that are inconsistent with the data. The only way to get the method to work in the centers of galaxies is to use prior information about the redshifts to rule out implausible centers. This suggests that the tilted ring ring method may not be producing reliable rotational velocities in the central kiloparsecs of dwarf galaxies.
MICROLENSING PARALLAX FOR OBSERVERS IN HELIOCENTRIC MOTION
Authors: Novati S. Calchi , Scarpetta G. 
Published: June 2016

ABSTRACT
Motivated by the ongoing Spitzer observational campaign, and the forthcoming K2 one, we revisit, working in an heliocentric reference frame, the geometrical foundation for the analysis of the microlensing parallax, as measured with the simultaneous observation of the same microlensing event from two observers with relative distance of order au. For the case of observers at rest, we discuss the well-known fourfold microlensing parallax degeneracy and determine an equation for the degenerate directions of the lens trajectory. For the case of observers in motion, we write down an extension of the Gould relationship between the microlensing parallax and the observable quantities and, at the same time, highlight the functional dependence of these same quantities from the timescale of the underlying microlensing event. Furthermore, through a series of examples, we show the importance of taking into account themotion of the observers to correctly recover the parameters of the underlying microlensing event. In particular, we discuss the cases of the amplitude of the microlensing parallax and that of the difference of the timescales between the observed microlensing events, which are key to understand the breaking of the microlensing parallax degeneracy. Finally, we consider the case of the simultaneous observation of the same microlensing event from the ground and two satellites, a case relevant for the expected joint K2 and Spitzer observational programs in 2016.
COSMIC REIONIZATION ON COMPUTERS. MEAN AND FLUCTUATING REDSHIFTED 21 cm SIGNAL
Authors: Kaurov Alexander A. , Gnedin Nickolay Y. 
Published: June 2016

ABSTRACT
We explore the mean and fluctuating redshifted 21 cm signal in numerical simulations from the Cosmic Reionization On Computers project. We find that the mean signal varies between about ±25 mK. Most significantly, we find that the negative pre-reionization dip at z ∼ 10–15 only extends to

, requiring substantially higher sensitivity from global signal experiments that operate in this redshift range (EDGES-II, LEDA, SCI-HI, and DARE) than has often been assumed previously. We also explore the role of dense substructure (filaments and embedded galaxies) in the formation of the 21 cm power spectrum. We find that by neglecting the semi-neutral substructure inside ionized bubbles, the power spectrum can be misestimated by 25%–50% at scales k ∼ 0.1–1h Mpc−1. This scale range is of particular interest, because the upcoming 21 cm experiments (Murchison Widefield Array, Precision Array for Probing the Epoch of Reionization, Hydrogen Epoch of Reionization Array) are expected to be most sensitive within it.
RELATIONSHIPS BETWEEN FLUID VORTICITY, KINETIC HELICITY, AND MAGNETIC FIELD ON SMALL-SCALES (QUIET-NETWORK) ON THE SUN
Authors: Sangeetha C. R. , Rajaguru S. P. 
Published: June 2016

ABSTRACT
We derive horizontal fluid motions on the solar surface over large areas covering the quiet-Sun magnetic network from local correlation tracking of convective granules imaged in continuum intensity and Doppler velocity by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory. From these we calculate the horizontal divergence, the vertical component of vorticity, and the kinetic helicity of fluid motions. We study the correlations between fluid divergence and vorticity, and between vorticity (kinetic helicity) and the magnetic field. We find that the vorticity (kinetic helicity) around small-scale fields exhibits a hemispherical pattern (in sign) similar to that followed by the magnetic helicity of large-scale active regions (containing sunspots). We identify this pattern to be a result of the Coriolis force acting on supergranular-scale flows (both the outflows and inflows), consistent with earlier studies using local helioseismology. Furthermore, we show that the magnetic fields cause transfer of vorticity from supergranular inflow regions to outflow regions, and that they tend to suppress the vortical motions around them when magnetic flux densities exceed about 300 G (from HMI). We also show that such an action of the magnetic fields leads to marked changes in the correlations between fluid divergence and vorticity. These results are speculated to be of importance to local dynamo action (if present) and to the dynamical evolution of magnetic helicity at the small-scale.
KINEMATICALLY IDENTIFIED RECOILING SUPERMASSIVE BLACK HOLE CANDIDATES IN SDSS QSOs WITH z < 0.25
Authors: Kim D.-C. , Evans A. S. , Stierwalt S. , Privon G. C. 
Published: June 2016

ABSTRACT
We have performed a spectral decomposition to search for recoiling supermassive black holes (rSMBHs) in Sloan Digital Sky Survey (SDSS) quasi-stellar objects (QSOs) with z < 0.25. Out of 1271 QSOs, we have identified 26 rSMBH candidates that are recoiling toward us. The projected recoil velocities range from −76 to −307 km s−1 with a mean of −149 ± 58 km s−1. Most of the rSMBH candidates are hosted by gas-rich luminous infrared galaxies (LIRGs)/ultra-luminous infrared galaxies (ULIRGs), but only 23% of them show signs of tidal features, which suggests that a majority of them are advanced mergers. We find that the black hole masses M
BH of the rSMBH candidates are on average ∼5 times smaller than those of their stationary counterparts and cause a scatter in the

relation. The Eddington ratios of all of the rSMBH candidates are larger than 0.1, with a mean of 0.52 ± 0.27, suggesting that they are actively accreting mass. Velocity shifts in high-excitation coronal lines suggest that the rSMBH candidates are recoiling with an average velocity of about −265 km s−1. The electron density in the narrow line region of the H ii rSMBH candidates is about 1/10 of that in active galactic nucleus (AGN) rSMBH candidates, probably because the AGN in the former was more spatially offset than that in the latter. The estimated spatial offsets between the rSMBH candidate and the center of the host galaxy range from 0.″21 to 1.″97 and need to be confirmed spatially with high-resolution adaptive optics imaging observations.
PIC SIMULATIONS OF THE EFFECT OF VELOCITY SPACE INSTABILITIES ON ELECTRON VISCOSITY AND THERMAL CONDUCTION
Authors: Riquelme Mario A. , Quataert Eliot , Verscharen Daniel 
Published: June 2016

ABSTRACT
In low-collisionality plasmas, velocity-space instabilities are a key mechanism providing an effective collisionality for the plasma. We use particle-in-cell (PIC) simulations to study the interplay between electron- and ion-scale velocity-space instabilities and their effect on electron pressure anisotropy, viscous heating, and thermal conduction. The adiabatic invariance of the magnetic moment in low-collisionality plasmas leads to pressure anisotropy,

, if the magnetic field

is amplified (

and

denote the pressure of species j (electron, ion) perpendicular and parallel to

). If the resulting anisotropy is large enough, it can in turn trigger small-scale plasma instabilities. Our PIC simulations explore the nonlinear regime of the mirror, IC, and electron whistler instabilities, through continuous amplification of the magnetic field

by an imposed shear in the plasma. In the regime

(

), the saturated electron pressure anisotropy,

, is determined mainly by the (electron-lengthscale) whistler marginal stability condition, with a modest factor of ∼1.5–2 decrease due to the trapping of electrons into ion-lengthscale mirrors. We explicitly calculate the mean free path of the electrons and ions along the mean magnetic field and provide a simple physical prescription for the mean free path and thermal conductivity in low-collisionality β

j
≳ 1 plasmas. Our results imply that velocity-space instabilities likely decrease the thermal conductivity of plasma in the outer parts of massive, hot, galaxy clusters. We also discuss the implications of our results for electron heating and thermal conduction in low-collisionality accretion flows onto black holes, including Sgr A* in the Galactic Center.
RESOLVE AND ECO: THE HALO MASS-DEPENDENT SHAPE OF GALAXY STELLAR AND BARYONIC MASS FUNCTIONS
Authors: Eckert Kathleen D. , Kannappan Sheila J. , Stark David V. , Moffett Amanda J. , Berlind Andreas A. , Norris Mark A. 
Published: June 2016

ABSTRACT
In this work, we present galaxy stellar and baryonic (stars plus cold gas) mass functions (SMF and BMF) and their halo mass dependence for two volume-limited data sets. The first, RESOLVE-B, coincides with the Stripe 82 footprint and is extremely complete down to baryonic mass M
bary ∼ 109.1
M
⊙, probing the gas-rich dwarf regime below M
bary ∼ 1010
M
⊙. The second, ECO, covers a ∼40× larger volume (containing RESOLVE-A) and is complete to M
bary ∼ 109.4
M
⊙. To construct the SMF and BMF we implement a new “cross-bin sampling” technique with Monte Carlo sampling from the full likelihood distributions of stellar or baryonic mass. Our SMFs exhibit the “plateau” feature starting below M
star ∼ 1010
M
⊙ that has been described in prior work. However, the BMF fills in this feature and rises as a straight power law below ∼1010
M
⊙, as gas-dominated galaxies become the majority of the population. Nonetheless, the low-mass slope of the BMF is not as steep as that of the theoretical dark matter halo MF. Moreover, we assign group halo masses by abundance matching, finding that the SMF and BMF, separated into four physically motivated halo mass regimes, reveal complex structure underlying the simple shape of the overall MFs. In particular, the satellite MFs are depressed below the central galaxy MF “humps” in groups with mass <1013.5
M
⊙ yet rise steeply in clusters. Our results suggest that satellite destruction and stripping are active from the point of nascent group formation. We show that the key role of groups in shaping MFs enables reconstruction of a given survey’s SMF or BMF based on its group halo mass distribution.