bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proposed Modification of Abandonment and Site Restoration Mechanism in Gross Split PSC for Marginal Field in Indonesia
Authors: Kurniawan Temmy Surya , Jaenudin Jemi 
Published: October 2017

Abstract
Referring to the Ministry of Energy and Mineral Resources regulation in 2017 number 8, the government intends to encourage contractor in Indonesia to conduct exploration and exploitation activity to be more effective and efficient in way of implementing gross split PSC in Indonesia, especially for expiry block. In 2018-2028, there will be 23 expired blocks. Some of those blocks have been reaching the marginal category and they are needed to be evaluated with current regulation of fiscal regime. In marginal block, abandonment and site restoration (ASR) cost is being issue for economic feasibility.
To evaluate impact of ASR mechanism in Indonesia's gross split PSC for marginal block, a model block is evaluated. The model has high cost per barrel (USD39/boe) and ASR cost is 34% of total cost. Economic evaluation for this marginal block with ASR issue is assessed using NPV as feasibility indicator. The evaluation result using Indonesia's gross split PSC is not favorable for contractor. This paper presents modification of ASR funding mechanism in Indonesia's gross split PSC.
Modification of funding mechanism consists of scenario with ASR cost is fully taken from government take, ASR cost is taken from government take when the cash flow of contractor is negative, and ASR cost is shared between government and contractor based on total split This modification gives positive result for contractor side.
The Study of a Novel Modified Silica Nanofluid for Pressure-Decreasing Application in the Ultra-Low Permeable Formation
Authors: Zhao Mingwei , Gao Mingwei , Dai Caili , Li Yuyang , Lv Wenjiao 
Published: October 2017

Abstract
In most low-permeability reservoirs producing regions of the world currently, for pressure continuous increase in the water-injection process is becoming increasing important issues when water flooding is conducted. In this work, a novel hydrophobic silica nanofluid (SNF) through modified by triethoxy(vinyl)silane (TVS) is adopted to adsorb on the surface of core so as to acquire hydrophobicity and decrease the water-injection pressure. Fourier transform infrared (FTIR) spectroscopy shows that methyl headgroups are successfully grafted on the surface of silica nanoparticles (SNP). The decrease of SHN (SHN) certifies the success of modification. Dynamic light scattering (DLS) result reflects that the modified SNF has excellent hydrophobicity and superior dispersibility. The wettability transformation of core surface from hydrophilic to lyophobic is determined by the water contact angles. The results of laboratory displacement tests show that the SNF has the remarkable pressure-decreasing ability due to adsorption on the surface of core.
Active Tag Control Sliding Sleeve Fracturing Technology
Authors: Lichen Zheng , Jiaqing Yu , Yucai Wang , yang Gao , Xiaohan Pei , He Liu 
Published: October 2017

Abstract
The rapid progress in fracturing technology pushes the oilfield development to bigger scale, The traditional Multi-stage fracturing technology such as ball fracturing, quick drillable bridge plug fracturing have problems like limited fracturing stages, high operation risk and high later operation cost etc. Multistage fracturing technology based on Radio Frequency Identification (RFID) was developed, it overcomes the shortcomings of traditional fracture tools, but the low tag recognition rate, speed limitation and complicated structure limit its further application. A new generation active tag control Sliding sleeve Fracture tool is developed. This fracture tool is composed of vacuum energy storage system, electric control direction valve, sliding sleeve, microcomputer control system, battery group, RFID antenna and active tag. The vacuum energy storage system provide power for the open and close of the sliding sleeve, the operating pressure is the union of the surface fracture pressure and the head of the liquid, which can be controlled on the ground. Electric control direction valve controls the oil flow direction and control the opening and closing of the sliding sleeve. The antenna works only in low power mode and picks the signal from the active tag. The active tag ball contains micro battery inside and signal producing system, it will be wake up by a special instrument before lower into the well, the battery will sustain the tag work for at least 30 minutes. The active tag signal can be picked up by the antenna at 100% success ratio and without speed limitation. During the fracturing process, the active tag will be dropped in the well to control the opening and closing of the sliding sleeve in any specific fractured interval. After fracturing, pressure wave is applied to open all the sliding sleeves and the production operation begins. Compared to the first generation RFID control sliding sleeve, the Active tag control sliding sleeve has relative simpler structure, more compact dimension, longer battery service life, more reliability and control flexibility, which is more suitable for the oil field fracture application. The active tag signal transfer mechanism improve signal transfer reliability greatly and without speed limitation, which lowers the power consumption of the antenna and will provide long battery service life, the vacuum energy storage system simplify the structure greatly and the sleeve active pressure can be controlled on the ground.
In-Situ Stress and Fracture Controls on Permeability Distribution within Walloon Subgroup, Surat Basin
Authors: Mukherjee Saswata , Copley Jeff , Esterle Joan 
Published: October 2017

Abstract
The Surat Basin Coal Seam Gas (CSG) is maturing from exploration to production to meet sales targets for several Liquefied Natural Gas projects. This requires effective and predictable reservoir performance that is controlled by permeability, gas saturation and matching the well completion technique to the ground conditions. Permeability in coal has major dependence on in-situ stress and natural fractures, and these will have characteristics that vary from field scale to larger regional scale faults and folds. This study investigates the spatial and stratigraphic variability of stress and fracture orientation relative to measured permeability within the Walloon Subgroup (WSG) that hosts CSG resources within the Surat Basin.
Open file wireline data from 33 vertical wells across the eastern part of the Surat Basin are used to calculate the in-situ stress orientation and fracture distributions within the WSG. Present day in-situ stress orientations were identified from the borehole breakout and drilling induced tensile fractures. Permeability data from 13 wells are compared using the in-situ stress and fracture data from image log interpretation.
CSG reservoir permeability is, in general sensitive to the changes in effective stress and primary permeability is reduced exponentially with increasing effective vertical stress. However, this relationship does not always hold true. Permeability within the WSG is also affected by the angle between present day in-situ stress orientation and fracture or joint trends and fracture dip angle. Wells in the relatively simple structural areas with subtle faulting show higher permeability when the coal fracture trends are parallel and up to 40 degrees to the present day in-situ stress. Permeability is significantly less outside this range. Most of the high permeability zones tend to occur in the areas where there is significant rotation of in-situ stress from the regional mean stress orientation (commonly ENE – WSW). The observed stress rotation is attributed to the stress perturbations mainly from folds and faults within the Surat sedimentary succession, suggesting local structural influence on the permeability distribution within the WSG. Few analyses of permeability versus stress and fracture properties are in the public domain for the Surat Basin. This study illustrates the connection between different structural domains, stress and fractures in previously unidentified areas of oblique-slip faulting, in some cases reactivating and in others creating new features from basement through the Jurassic to Tertiary succession.
Effect of Casing Coating Materials on Shear-Bond Strength
Authors: Jadhav Rahul , Palla Venkata Gopala , Datta Amlan , Dumbre Maithili 
Published: October 2017

Abstract
A well-executed cement operation is fundamental for successful zonal isolation. One method used to confirm the success of a cementing operation is cement bond-log (CBL) analysis. Various factors contribute to good bond strength at the casing-cement interface; a better shear bond helpsminimize the risk of communication between different zones and also maximize production by avoiding undesirable fluid diversion during well intervention. To enhance shear-bond strength, a thin layer of coating material can be applied on the external surface of casing before running itin the well. Variouscoating techniquesare available, such as spraying, dipping, or simply brushing. Polymer emulsions, thermosetting polymers, and inorganic-based coatings can be applied. This paper studies the effect of various coating materials on shear-bond strength.
A coated casing sample was concentrically placed inside another largercylinder and cured after filling the annular space with cement slurry. Once cured, the shear-bond strength was experimentally measured using a hydraulic press. The results obtained with various coating materials are compared to those from an uncoated control sample.
The shear-bond setup was prepared with neat standard cement slurry and cured for 3and 7days for testing. Three different types of casing coating wereevaluated for enhancing shear-bond strength—inorganic-based, aqueous polymer emulsion, and thermosetting resin. All three coatings providedenhanced shear-bond strength compared to the control sample. The inorganic-based coating almost doubled the shear-bond strength. The aqueous polymer emulsion coating increased shear bonding by approximately 30%. Finally, the thermosetting resin coating resulted in a much smaller increase in shear bonding compared to the other treatments; however, it was observed to provide better resiliency while applying loads during testing.
A thin layer of coating onthe entire length of a casing column does not significantly increase costs. On the contrary, significant value is providedthrough better shear-bond strength and potential corrosion resistance. Therefore, this practice can eliminate the necessity of remedial treatments later. Additionally, applying the inorganic-based coating on the outer surface of casing pipe provides additional bond-strength between the cement and casing, minimizing the risk of inner debonding.
The coating application process is operationally simple and can be readily implemented, and it provides a low-cost, dependable barrier. In addition to providing better bonding, coating can also inhibit corrosion and increase the life of the tubular.
Refactoring Carbonate Reservoir Architecture through Real-Time LWD Measurement
Authors: Hassan N. A. , Syailendra A. A. , Hanalim L. , Santoso G. I. , Alang K. A. 
Published: October 2017

Abstract
X Field is a carbonate platform setting in Central Luconia, Malaysia. The field faced declining trend of gas production due to early water rise. Seismic attribute shows that the rising water was assumed to be related to the water being drained through crossflow into the possible karst feature, which may have acted as conduit located near the existing production well bore. Two horizontal infill wells were planned in this field with the objectives to accelerate the gas production, and to investigate the uncertainty on the current gas water contact (GWC) movement, karst feature and fracture identification in single run LWD. The horizontal well placement strategies were set in different workflows as some key reservoir parameters are still uncertain. Several scenarios were made based on real-time reservoir characterization and observation, then they were translated into different production performance profiles. To achieve those well objectives, a new technology approach was proposed that consisted of the latest reservoir mapping while drilling technology with the capability to map the reservoir structure and fluid contact within 35m depth of investigation. This was combined with the full suites of log measurement including neutron, density and sonic data for secondary porosity measurement to support the real-time petrophysical and well placement decision making. The two horizontal infill wells were planned to stay close to the top of carbonate and to avoid the water contact as much as possible in order to optimize the gas production. The second well would depend on the first well reservoir observation result. On this case study, the application of reservoir mapping technology while drilling has successfully demonstrated the well placement as close as 7m TVD below the reservoir roof and mapping the gas water contact at 30m TVD below the trajectory. The actual GWC was detected 25m shallower than prognosed, so the finding of this first well has led to the decision to eliminate the drilling of the second well, which resulted in a cost saving of more than USD 20 million. Other than that, the qualitative result from reservoir mapping tool provided a new understanding of carbonate reservoir modeling, which confirmed the interpretation, current GWC and reservoir heterogeneity characterization both vertically and laterally. This strategy could be replicated in other carbonate reservoirs to delineate current gas water contact without physically penetrating it. Karst and secondary porosity interpretation were used for completion optimization and to maximize the production.
Integration of Time-Lapse Pressure Transient Analysis in Reservoir Characterization and Reducing Uncertainty of Initial Gas-in-Place Estimation: A Case Study in Gas Condensate Reservoir
Authors: Rushatmanto M. , Sianturi J. , Suwito E. , Priskila L. M. 
Published: October 2017

Abstract
Tunu is multilayer gas field operated by Total EP Indonesie in Kutai Basin, which produced since 1990. It consists of thousands of gas-bearing sandstone reservoirs; spread over 2000 meters of vertical gross thickness. The depositional environment is deltaic, dominated by distributary channels and mouth bars.
Estimation of Initial Gas In-Place (IGIP) is important for gas field development. Well testing by recording bottom-hole pressure to conduct Pressure Transient Analysis (PTA) should not be limited to classical approach of determining permeability and skin parameters. Moreover, integration of time-lapse PTA can be very useful to reduce uncertainty of IGIP estimation as well as to access reservoir dimension when all reservoir boundaries are reached.
The advantage of time-lapse PTA with material balance model over classical P over Z (P/Z) method is capable to model reservoir dimension using either analytical or numerical. Other advantage is able to detect any transmissivity change due to fluid contact such as Gas Oil Contact (GOC) or Gas Water Contact (GWC). Estimation of IGIP using PTA from well testing is possible to be carried out before the well put on production or afterward, conversely P/Z method requires the well to be produced for quite some time to have pressure depletion.
DST survey in most of cases is carried out with limited duration in order to minimize operational cost related to rig time. Therefore conducting another well testing after well completion is useful when survey duration is more flexible as no time limitation associated to rig time. Furthermore well testing duration can be designed accordingly until all boundaries are reached in order IGIP can be estimated and reservoir dimension can be modeled accordingly.
This paper demonstrates the added value of time-lapse PTA in gas condensate reservoir. The integration of time-lapse well testing with the incorporation of one year of well production is considered as a good practice in reducing IGIP estimation and accessing reservoir dimension. Interference test was done to access reservoir connectivity between two wells where seismic interpretation shows different channel body. Based on connectivity between wells that penetrate channel reservoir 4d, material balance PoverZ (P/Z) to estimate Connected Gas In Place (CGIP)can be carried out accordingly.
Supervisor Performance Assessment Method Based on AHP
Authors: Zhang Shaohui , Wang Shuai , Wang Ling , Liu Xiaochen , Teng Xinxing 
Published: October 2017

Abstract
In the process of petroleum exploration and development, the front-line supervisors have played an important role in ensuring the operation quality and safety. The supervisor performance assessment is the core of supervisor management. However, the traditional performance assessment only focuses on the written test and interviews, with single standard, more qualitative judgment and less quantitative analysis. The performance assessment results are greatly influenced by human factors, being lack of scientificity and fairness.
In order to further improve the supervisor performance assessment system, the performance assessment hierarchical structure model for the supervisor has been established with the use of analytic hierarchy process (AHP). The work capacity, work performance, professional ethics, skills examination, daily training and coworker evaluation are taken as assessment criteria. The weight of each criterion is determined by establishing the judgment matrix, checking the consistency and calculating the weight. In addition, the supervisor performance assessment management software has been designed, which will be conducive to the application of this performance assessment method in oilfields.
The new performance assessment method for the supervisor not only realizes the combination of qualitative analysis and quantitative analysis, but also realizes the combination of dynamic evaluation and 360 degree feedback. Based on the performance assessment results, the level-to-level management of supervisor has been realized. In addition, the salaryis directly determined by the performance assessment results. Moreover, the supervisor is selected and assignedaccording to the performance assessment results.
The establishment and application of supervisor performance assessment system provide a more reliable basis for the supervisor management and selection, and realize scientific and reasonable assessment of the supervisor.
Investigation on the Failure of the Bearing Mechanisms of the Marine Turbine on an FPSO Operating in Vietnam Waters
Authors: Vijayaraghavan Vijay 
Published: October 2017

Abstract
Marine turbine bearings are very susceptible to failures through number of different mechanisms such as wear, fatigue and mechanical damages due to the conditions it operates in. The failure of this particular thrust bearing lead to the whole turbine being shut down as a result sizing of the shaft and In this study failed part of a thrust bearing related to a 20.4 MW GE LM 2500 Marine Gas turbine was examined and findings was presented below.
Large amounts of surface cracks, noticeable changes of the failed surface with significant escalation of surface hardness were the main results. The studies revealed that the bearing part coming loose and shifting into dis-proponate clearance producing relative displacements under cyclic gradient loading. This condition grossly reduced the service life of turbine journal bearing via failure through fretting fatigue mechanism.
Surface Controlled In Situ Gas Lift for Appraisal of Oil Reservoir in a Gas Well
Authors: Hamza N. , Baghdadi F. , Ibrahim S. Y. , Madon B. 
Published: October 2017

Abstract
Gas lift is an artificial lift technique, using injected gas from the tubing-casing annulus to aerate the fluid column to reduce its density. The formation pressure is then able to life the fluid column and forces the fluid out of the wellbore. The same application can be provided through many different deployment strategies. The most common deployment would be through a downhole gas lift mandrel and valve, with gas supplied by a surface gas compressor. The gas lift rate is mainly controlled by the compressor discharge pressure, well pressure as well as the orifice size of the operating gas lift valve.
An alternative deployment available is called Auto Gas lift (AGL). The main difference is on the gas lift source, where AGL taps into an existing gas reservoir. The gas lift rate is controlled by an Inflow Control Valve (ICV) which operated through a hydraulic line.
In an existing well, AGL may still be pursued even though there is no possibility of deploying an ICV. Instead, once perforation to the gas reservoir is made, a tubing patch with a preinstalled gas lift valve can be installed. The main limitation for this application would be on the tubing patch installation, the resulting ID restriction as well as the operation required to change the injection rate or to close in the gas interval.
This paper will discuss the first application of AGL with surface control to appraise an oil reservoir in an existing gas well. The application eliminated requirement of coil tubing deployed 13Cr tubing patch and gas lift valve installation. The methodology used to evaluate the application is described and its results discussed and compared to the actual well result.
Smart Nanoparticles for Conformance Improvement in Waterflooding
Authors: Temizel Cenk , Putra Dike , Zhang Ming , Moreno Raul 
Published: October 2017

Abstract
Per recent analyses, in the near future, over half amount of the oil extracted globally, will require some form of enhanced oil recovery (EOR) techniques. Existing literature and historical investigations suggest that in oil reservoirs having viscosities between 10 – 150 m.Pa.s, there is a significant potential for tertiary recovery through the application of polymer flooding. For reservoir oil viscosities above 150 mPa.s, the polymer pumping efficiency goes down as polymer injectivity reduces significantly with increasing injection water viscosity that are used to attain a favorable mobility ratio at such high oil viscosities. To overcome this limiting factor, in this study, we propose the use of supramolecular assemblies (SMA) that have adjustable viscosity properties. Complexation of long-chain amino-amides and maleic acid is used to make these assemblies, which allow it to have reversible viscosity depending on the solution pH level.
To maintain high injection efficiency, during pumping, SMA solutions will be kept at low viscosity values. On entry in deep reservoir or at oil contact phase, through introduction of an external stimulus the viscosity of SMA solution will be reversed to a much higher viscosity. This will allow to sufficiently improve the mobility ratio. Preliminary results from lab-scale studies have indicated that along with reversibly adjustable viscosity property, SMA solutions are also tolerant to high temperatures and salt concentrations.
Supramolecular solutions can be considered as healable polymer systems, since unlike conventional polymer they disassemble and re-assemble when exposed to high temperature and stress conditions. In such conditions, conventional polymers generally undergo degradation. Additionally, through molecular scission processes SMA solutions can also be used in highly confining environments as well as in permafrost conditions and thin zones where conventional thermal techniques are not applicable.
The objective of this work is the development of novel SMA system that have the aforementioned properties of reversibly adjustable viscosity through pH, tolerance to high temperature and salt concentrations through desired interfacial properties. Lab-scale preliminary results have shown the potential economic benefits of the use of SMA solutions on a field-wide scale. Based on the results, it must be emphasized that SMA systems have a worldwide application in oil reservoirs for EOR purposes.