bluuebunny/crossref_metadata_2025_split huggingface dataset:
Incorporating the Effect of Pyrite on Total Organic Carbon Estimation in Eagle Ford Shale
Authors: Jiang Shuxian , Mokhtari Mehdi , Borrok David M 
Published: August 2017

Abstract
Ignoring the presence of pyrite can lead to errors in the estimation of Total Organic Carbon (TOC) since pyrite has significantly higher density and conductivity compared to other minerals in shale formations. This study aims to improve the accuracy of estimating TOC from well log data by accounting for the pyrite effect in Eagle Ford shale. To this end, more than 50 feet of preserved cores samples from the Eagle Ford were analyzed using laboratory pyrolysis, X-ray fluorescence (XRF), X-Ray Diffraction (XRD), and spectral core gamma system.
Since there is significant vertical heterogeneity in the Eagle Ford shale, parameters such as TOC, pyrite content, Gamma ray intensity, content of Fe and S, and concentrations of U, Th, and K were analyzed on a fine scale in the Upper and Lower Eagle Ford respectively. Analysis of laboratory TOC data were applied to calibrate TOC data using geophysical well logs methodologies. Pyrite data from XRD analysis were used to find the relationship between pyrite and organic matter and to determine the effect of pyrite on well logs. Well-log-based TOC calculation methods were improved by considering pyrite as an adjustable parameter in equations. Schmoker's (1983) four-component system rock model and Alfred and Vernik's (2013) two-pore system model are two representatives of density-log-based TOC calculation methods. Based on these two models, a new petrophysical model considering pyrite and organic porosity was developed.
In this research, empirical correlation between TOC and pyrite was explored. Changes of Fe and S concentrations with depth and Gamma ray intensity was determined. The trends of Fe sand S contents matched Gamma ray intensity very well in the depth range from 13790 ft to 13825 ft. Empirical relationships were found between TOC and Gamma ray intensity, TOC and Uranium, respectively. Furthermore, a new petrophysical model considering pyrite and organic porosity was validated with TOC and density data from shale formations. The proposed model improves the estimation of TOC calculation in Eagle Ford formation by the incorporation of pyrite effect.
A Two-Phase Flow Model for Fractured Horizontal Well with Complex Fracture Networks: Transient Analysis in Flowback Period
Authors: Chen Zhiming , Yu Wei , Liao Xinwei , Zhao Xiaoliang , Chen Youguang , Sepehrnoori Kamy 
Published: August 2017

Abstract
Model developments for transient analysis of fractured horizontal wells have gained tremendous attention in tight reservoirs, especially, during the flowback period. However, the existing models so far have rarely considered two-phase flow and complex fracture networks. To improve this situation, in this work, we present a new semianalytical two-phase flow model. Water and oil simultaneously flow in the matrix and fracture networks. By iteratively correcting the relative permeability to water and gas phases, we incorporate the two-phase flow into fracture model. Complex fracture networks with arbitrary geometries are described and the fluid flow interplays at fracture intersections are eliminated through mass balance equation. The model solution is obtained by using Laplace transform inversion, and it is verified by performing a case study with a numerical simulator. Our results show that there exist two distinct flow regimes: fluid feed and pseudo-boundary dominated flow (PBDF), which is generated by the permeability contrast between fracture networks and matrix. We also investigate the impacts of some key reservoir and fracture properties on the characteristics of productivity index. Results indicate that the productivity index increases with an increase in initial water saturation. Furthermore, it is found that during the PBDF, different fracture-network parameters have various constant productivity indexes, providing an efficient tool to characterize the fracture networks. Based on that, we apply the model to estimate the fracture networks of a tight-oil well in CJ formation at Tarim Bain with flowback data and micro seismic data, which provides an efficient technique to estimate the stimulation effectiveness during the flowback period.
Complex Toe-to-Heel Flooding: A Completion Strategy to Increase Oil Recovery from Sandstone Formations
Authors: Algarhy Ahmed , Soliman M. Y. , Heinze Lloyd , Gorell Sheldon , Henderson Steven , Nasr-El-Din Hisham 
Published: August 2017

Abstract
Because any increase in hydrocarbon recovery helps the petroleum industry respond to the ever-increasing demand for energy, increasing recovery from both conventional and unconventional reservoirs is the primary goal of developing new completion strategies. This paper introduces a new completion strategy, called Complex Toe-to- Heel Flooding (CTTHF), that increases oil recovery from sandstone formations. It then confirms the viability of CTTHF by using a commercial reservoir simulator to compare CTTHF to conventional waterflooding and Toe-to- Heel waterflooding. Finally, it presents several different methodologies for implementing CTTHF successfully, efficiently, and cheaply.
CTTHF improves reservoir management and enables better oil recovery than do other methods. It begins with the injection of a highly viscous slug near the toe of a horizontal well to form an impermeable barrier. An appropriate plug is then set to separate the perforations used to inject the barrier from the rest of the well. Then, the entire horizontal section of the well is perforated and a suitable packer is set to separate the horizontal section into a flooding zone (the perforations immediately heel-side from the plug) and production zone. The flooding zone is then used to create an injector hydraulic fracture into which water is injected to flood oil towards the production zone. As the flood material to oil ratio increases, the packer can be moved heel-ward. The oil is produced from the annulus through dual tubing completion or by any other convenient method, and the flood material can be either liquid or gas, depending on the application.
Though CTTHF is more complex than conventional strategies, it enables better recovery and can be implemented using a variety of completion techniques and technologies. Because the location of the packer can be changed, moreover, CTTHF minimizes the production of flood material. It is also compatible with dual tubing, coil tubing, and annulus production, and its design can be optimized using a variety of tubes, plugs, and packers.
Polyelectrolyte Complex Stabilized CO2 Foam Systems for Hydraulic Fracturing Application
Authors: Anandan Rudhra , Johnson Stephen , Barati Reza 
Published: August 2017

AbstractHydraulic fracturing of oil and gas wells is a water intensive process. Limited availability, cost and increasing government regulations restraining the use and disposal of fresh water have led to the need for alternative fracturing fluids. Using CO2 foam as a fracturing fluid can drastically reduce the need for water in hydraulic fracturing. We address the addition of polyelectrolyte complex nanoparticles (PECNP) to surfactant solutions to improve foam stability, durability and rheological properties at high foam qualities. Polyelectrolyte pH and polyanion/polycation ratios were varied to minimize particle size and maximize absolute zeta potential of the resulting nanoparticles. Rheological tests were conducted on foam systems of varying surfactant/PECNP ratios and different foam quality to understand the effect of shear on viscosity under simulated reservoir conditions of 40°C and 1300 psi. The same foam systems were tested for stability and durability in a view cell at reservoir conditions. Supercritical CO2 foam generated by surfactant alone resulted in short lived, low viscosity foam because of surfactant drainage from foam lamellae. However, addition of PECNP strengthens the foam film by swelling the film due to increased osmotic pressure and electrostatic forces. Electrostatic interactions reduce dynamic movement of surfactant micelles, thereby stabilizing the foam lamellae, which imparts high durability and viscosity to supercritical CO2 foams. From the rheology test results, it was concluded that increasing foam quality and the presence of PECNP resulted in improved viscosity. Also, foam systems with PECNP showed promising results compared with foam generated using surfactant alone in the view cell durability test. The addition of optimized polyelectrolyte nanoparticles to the surfactant can improve viscosity and durability of supercritical CO2 foam during hydraulic fracturing, which can lead to large reductions in water requirements.
Stacked Pay Pad Development in the Midland Basin
Authors: Alimahomed Farhan , Malpani Raj , Jose Rohann , Haddad Elia , Arteaga Edgar V. , Smith Lance , Lati Shrutesh 
Published: August 2017

Abstract
The Midland Basin has seen an unprecedented boom in pad drilling over the last year, largely due to the stacked pay, comprising of the Spraberry and the Wolfcamp formations. Operators are targeting up to four different reservoirs in one section, using a wine-rack pattern, which is the future of pad drilling. The workflows discussed in this paper will help us in understanding the growth of the hydraulic fractures and their production interference with the offset wells. These integrated workflows are centered on building a calibrated 3D model, to perform predictive modeling on various combinations of stacked laterals and determine the optimum spacing, both vertically and laterally.
Technology integration plays a significant role in identifying the key drivers of production. Our workflows involve building a geomodel using high tier pilot well logs and utilizing an unconventional fracture model (UFM) to simulate hydraulic fractures to understand the overall fracture footprint. The fractures are then gridded in an unstructured manner and fed to a numerical reservoir simulator to perform production history matching. This is the most crucial step in the process because this calibrated model is then usedfor predictive modeling of the various combinations of lateral spacing and stacking.
Pilot well logs show varying degrees of high stress barriers that exist across the basin, and knowing the stress regime local to a field or section is important in determining the optimum landing locations and completion designs. Typical pump schedules for the zones of interest were selected based on current industry practices. Fully 3D planar fracture simulations performed on the pilot well resulted in 18 potential landing locations spanning the Upper Spraberry to the Lower Cline, based on fracture heights and theinterference between the zones. Out of the 18 targets, fivewere selected based on production potential. UFM simulations along the lateral show different fracture geometries in different reservoirs due to varying rock properties and natural fracture orientations. The production history matching was performed using a P50 type curve generated using public data for eachreservoir in the county, and using known reservoir fluid properties.
The modeling approach discussed in this paper can be applied to any data set within the basin to determine the optimum landing location, which could vary depending on changing reservoir properties. It acts as an alternative approach to field testing varying spacing combinations, which could be both, expensive and time consuming.
Low Density Proppant in Slickwater Applications Improves Reservoir Contact and Fracture Complexity - A Permian Basin Case History
Authors: Jackson Kale , Orekha Olatunji 
Published: August 2017

Abstract
The use of slickwater fluid systems in hydraulic fracture design has grown tremendously in recent years relative to "conventional" linear gel or cross-linked fluid systems. The primary drivers for this change in design methodology are cost, proppant pack damage minimization, fracture complexity and environmental footprint. The efficiency of proppant placement in the fracture using slickwater systems remains a subject of ongoing research none-the-less.
The diminished capability of slickwater systems to effectively suspend and transport proppant in a fracture (and the wellbore) due to its relatively low viscosity is well known, and presents the most significant drawback of utilizing slickwater systems. This inferior transport behavior requires that fracture designs consist of low proppant concentrations (0.25 – 2.0 PPA, typically) and leads to the requirement of very large volumes of fluid for placement. Furthermore, the majority of slickwater completion designs in recent times have incorporated a high percentage of small mesh size proppant (100 Mesh and 40/70) into the pump schedules to afford placement in these thin fluid systems, which have impacted proppant pack conductivity.
This paper will present a new low density proppant that has been developed to enhance the transport capabilities of slickwater fluids leading to increased reservoir contact area while enhancing proppant pack conductivity. Proppant performance in slot flow testing in comparison with conventional proppant will be presented as well as various novel deployment methodologies in which the proppant can find optimal applications by leveraging its lightweight characteristics which can lead to longer effective half lengths and greater frac height. Finally, the authors will present a case study detailing the successful deployment of the new Ultra Lightweight Ceramic (ULWC) proppant in the 2nd Bone Spring formation of the Permian basin. Lessons learned and benefits to the overall completions design will also be discussed.
Completions engineers, reservoir engineers and all technical stakeholders who are actively developing or plan to develop acreage in unconventional resource shale plays where the use of slickwater fracture fluids systems are currently in high utilization will find this paper beneficial.
Simplifying Wellhead Facilities for Multiphase Production
Authors: Gupta A.. , Pitts J.. 
Published: August 2017

Abstract
Liquids-rich gas plays present significant challenges to producers to keep wells flowing and maximize production. In particular, liquid loading is a frequent issue as production rates decline and flow rates are no longer sufficient to keep liquids entrained in the gas stream. Many strategies exist and have been attempted over the years for attempting to keep these wells flowing and avoid liquid loading.
Perhaps the most attractive option is wellhead compression, which will lower wellhead pressures and increase flowrates, both items necessary to eliminate liquid loading. By reducing wellhead pressures, compressors will also increase the recoverable assets of a well. Traditional compression is not able to operate with liquids present and thus requires additional infrastructure and facilities to separate, store, and transport the liquids. Multiphase production facilities are a good solution to eliminate the need for additional infrastructure at the wellhead, and instead move the multiphase flow downstream to a central facility for processing. However, the more common multiphase pump technologies suffer from low efficiencies in the high gas volume fraction (GVF) conditions typical in liquids-rich gas wells.
A new multiphase compression technology is identified with the potential to achieve the benefits of multiphase production while operating at efficiencies closer to a traditional compressor. Testing is conducted with the new technology on several different wet gas wells in the Eagle Ford. Testing shows that the compressor is successfully able to handle a multiphase stream coming directly from the well without any additional separation facilities. Additional testing further demonstrates that the compressor may even be able to unload a well that is already loaded.
Further testing and development work will be required to broaden the conditions at which the compressor can operate and to prove that it can successfully maintain a variety of different wells flowing above their critical rates and unloaded. Initial indications are very promising and suggest that the new compressor technology will be a powerful tool for producers to use in maximizing the production of liquids-rich wells.
Mobile Mindfulness Intervention on an Acute Psychiatric Unit: Feasibility and Acceptability Study
Authors: Mistler Lisa A , Ben-Zeev Dror , Carpenter-Song Elizabeth , Brunette Mary F , Friedman Matthew J 
Published: August 2017

Background
Aggression and violence on acute psychiatric inpatient units is extensive and leads to negative sequelae for staff and patients. With increasingly acute inpatient milieus due to shorter lengths of stay, inpatient staff is limited in training and time to be able to provide treatments. Mobile technology provides a new platform for offering treatment on such units, but it has not been tested for feasibility or usability in this particular setting.

Objective
The aim of this study was to examine the feasibility, usability, and acceptability of a brief mindfulness meditation mobile phone app intended to reduce anger and aggression in acute psychiatric inpatients with schizophrenia, schizoaffective disorder, or bipolar disorder, and a history of violence.

Methods
Participants were recruited between November 1, 2015 and June 1, 2016. A total of 13 inpatients at an acute care state hospital carried mobile phones for 1 week and were asked to try a commercially available mindfulness app called Headspace. The participants completed a usability questionnaire and engaged in a qualitative interview upon completion of the 7 days. In addition, measures of mindfulness, state and trait anger, and cognitive ability were administered before and after the intervention.

Results
Of the 13 enrolled participants, 10 used the app for the 7 days of the study and completed all measures. Two additional participants used the app for fewer than 7 days and completed all measures. All participants found the app to be engaging and easy to use. Most (10/12, 83%) felt comfortable using Headspace and 83% (10/12) would recommend it to others. All participants made some effort to try the app, with 6 participants (6/12, 50%) completing the first 10 10-minute “foundation” guided meditations.

Conclusions
This is the first known study of the use of a commercially available app as an intervention on acute psychiatric inpatient units. Acutely ill psychiatric inpatients at a state hospital found the Headspace app easy to use, were able to complete a series of meditations, and felt the app helped with anxiety, sleep, and boredom on the unit. There were no instances of an increase in psychotic symptoms reported and there were no episodes of aggression or violence noted in the record.
BIOLOGI DAN NERACA HAYATI KUTU PUTIH PEPAYA PARACOCCUS MARGINATUS WILLIAMS & GRANARA DE WILLINK (HEMIPTERA: PSEUDOCOCCIDAE) PADA TIGA JENIS TUMBUHAN INANG
Authors: Maharani Yuni , Rauf Aunu , Sartiami Dewi , Anwar Ruli 
Published: August 2017

Biology and life table of papaya mealybug Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae) on three host plant species. The papaya mealybug, Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae), has been considered as a new invasive pest causing heavy damage on papaya in Indonesia since 2008. The pest is polyphagous with more than 55 host plant species. Study was conducted in laboratory with the objectives to determine developmental biology and life table parameters of the mealybug feeding on papaya, physic nut, and cassava leaves. Host plant species affected papaya mealybug performances. Egg stage lasted 7.25, 8.09, and 9.86 d on papaya, physic nut, and cassava, respectively. The shortest female nymphal developmental time was on papaya (18.91 d) and the longest on cassava (32.45 d). Longevity of adult males ranged from 1.09-2.85 d while females 12.29-14.93 d. When the mealybugs were reared on a seedling, the fecundity was higher on papaya (324.6) than those on physic nut (186.6) and cassava (157.5). No egg production occurred in virgin females. The sex ratio of P. marginatus favoured females, which comprised about 90% of population on papaya and cassava. The intrinsic rate of increase (rm) was significantly different among hosts, with the highest rate (0.117 female offspring/female/d) on papaya, followed by physic nut (0.079) and cassava (0.057). The maximum values of rmalong with net reproductive rate (Ro) and finite rate of increase(λ), and the shortest mean generation time (T) and doubling time (Dt) on papaya, indicating that papaya was the more favorable host plant for P.marginatus.
HERITABILITAS, NISBAH POTENSI, DAN HETEROSIS KETAHANAN KEDELAI (Glycine max [L.] Merrill) TERHADAP SOYBEAN MOSAIC VIRUS
Authors: Sa’diyah Nyimas , Akin Hasriadi Mat , Putri Ria , Jamil Risa , Barmawi Maimun 
Published: August 2017

Heritability, potential ratio, and heterosis of soybean (Glycine max [L.] Merrill) resistance to soybean mosaic virus. The use of soybean cultivars with resistance to SMV is a way for controlling soybean mosaic disease. The objective of this research was to estimate the disease severity, the narrow sense heritability, potential ratio and heterosis of resistance character and number of pithy pods, number of healthy seeds, and healthy seeds weight per plant of ten F1 populations of soybean crossing result to SMV infection. The experiment was arranged in a randomized complete block design in two replications. Observed characters were disease severity, number of pithy pods, number of healthy seeds, and healthy seeds weight per plant. The result of this research showed that 1) the crossing combinations those which were resistant to SMV (lower disease severity) were Yellow Bean x Tanggamus, Tanggamus x Orba, and Tanggamus x Taichung, 2) the narrow sense heritability of disease severity was included in medium criteria, 3) number of pithy pods belonged to high criteria, and 4) number of healthy seeds and healthy seeds weight per plant were included in low criteria. The crossing combinations that had low estimation value of heterosis and heterobeltiosis of resistance to SMV infection were Yellow Bean x Taichung, Bean x Tanggamus and Tanggamus x B3570. Disease severity or resistance to SMV is influenced by genetic and environmental factors.