bluuebunny/crossref_metadata_2025_split huggingface dataset:
Practices of the Integrated Management System for Injection Water in Brown Field –Case Study
Authors: He Liu , Shujun BAO , Zixiu Yao , Fuchao Sun , Jiaqing Yu , Deli Jia , Yang Gao 
Published: October 2016

Abstract
As the exploration degree and strength are continuously increased, both average water cut and natural decline rate have the tendency for increase. Hence various problems and contradictions are exposed, it's increasingly difficult to offset the influence of production decline and water cut increase on petroleum production, which severely impacts reservoir development efficiency and economic benefit. Prominent contradictions are as follows. 1) After an oilfield enters into a high water cut stage, the conflict between injection and production is very serious, such as unequal water-flooding producing reserves, high injection pressure of some water-injecting wells, low productivity of partial oil wells because of blocking created by mechanical impurities, and poor layering water-injection technique. 2) Affected by reservoir heterogeneity and water injection, Injection profile is non-uniform in longitudinal direction, water-flooding hierarchy and degree of reserve recovery of high permeability layer is relatively high as a result. The water flooding development effect of high water cut oil field is in urgent need of improvement. 3) Influenced by reservoir's poor connectivity and injection water quality, the injection pressure is high for some injection wells, resulting to a decline of injected water volume, which couldn't meet the demand of injection allocation. To solve the above problems, it is necessary to build an integrated management system for injection, which could both cover the underground and above-ground. In the meantime, technical efficiencies should also be improved. Injection-production network is further perfected, which aids to solve the problem of lack of water injection well spots and unbalance of injection and production; Based on hydrodynamic principle, kinds of injection allocation regimes are implemented; Injection of under-injected wells is enhanced, which increases the water-drive swept volume; Tests of layering distributional injection and profile control are also conducted using various methods; Finally, quality analysis & investigation and compatibility research of injected water are completed, reasonable treatment is done according to the compatibility, which improve the quality of injected water.
Innovative Experimental Design Workflows for Coupled Models
Authors: Swarbrick Thomas , Muller Mathieu 
Published: October 2016

Abstract
The Wheatstone and Iago gas fields, located approximately 110 km northwest of Barrow Island in the Carnarvon Basin, are developed through a common subsea and offshore platform infrastructure. The production forecasts for the Wheatstone Project are generated using reservoir simulation models for both fields coupled to a shared production network model. This ensures the appropriate representation of boundary conditions on the production system, such as well back-pressures. Typical forecasting workflows in a greenfield environment include running experimental design (design of experiments) to generate probabilistic forecasts of field responses. However, conventional experimental design workflows are based on simulations of a single field and are often completed without coupling the reservoir model to a production network model.
This paper will discuss the improvements to conventional simulation workflows made by the Wheatstone Reservoir Engineering Team. These refinements, which enabled running experimental design with both reservoir models coupled to a production network model, allowed responses to be generated and reviewed at the project level. This approach accounted for field interference through the production network and afforded the opportunity to understand the production interactions and relationships more accurately and thereby establish a vantage point for improved optimisation. The improvements were necessary to overcome some of the commercial and in-house software limitations constraining the workflow and results.
This type of simulation workflow had not been achieved to this extent previously within Chevron Corporation. The approach described here allowed the direct generation of project level responses, such as timing of future drilling campaigns, which would not have been practical or reliable otherwise. Future improvements of this modelling workflow will consist of standardising the workflow within the Corporation, using it for history matching later in life as well as decreasing cycle time on more routine simulation work.
Predictions of Relative Permeability for Low Permeability Reservoirs and its Scale Effect
Authors: Lei Zhengdong , Liu Tong , Xie Chiyu , Wang Moran , Zhang Zike 
Published: October 2016

Abstract
Nowadays, reservoirs with a low or extremely low permeability are of crucial importance for additional oil/gas recovery. Better understandings of multiphase displacement at pore scale in such unconventional reservoirs are necessary. Since the microscale interfacial transport plays a very important role in such processes, researchers were devoted to discover phenomenon at smaller and smaller resolution, and even further to nanoscale. However, this is extremely consuming on both experimental techniques and computation resources. Therefore, we are wondering whether there exists a cut-off resolution or not, below which the absolute and relative permeability are changeless.
In this study, the Navier-Stokes equation for fluid flow is directly solved through porous media. For two-phase flow, the volume-of-fluid method is applied. The numerical code is written within the framework of OpenFOAM, which is a widely used open source CFD solver recently.
The method is validated through several testing cases, which indicates the accuracy of capturing the interface action, wetting phenomenon, and permeability. After validations, we perform a series of modeling of single-phase and two-phase flow simulations in low permeability reservoirs, with special focus on the scale effect. The rock samples are taken from the low-permeability Changqing oil field in China. We reproduce the digital rock structures at various scales by using the micro-CT scanned data. The results indicate that the scanning scale has great impact on the predicted permeability, and the reservoir permeability increases with resolution due to the increasing of micro pore connectivity. However, this tendency is found to decline when reaching a higher resolution.
Case Study of Blocking Water Coning in Horizontal Well for Steam Stimulation in Heavy Oil Reservoir
Authors: Yu H. , Li L. , Zheng J. , Fu X. , Ji W. , Gao W. , Liu H. , Liu Y. , Yan F. , Luo C. , Liu J. , Zhang P. , Li T. , Han X. 
Published: October 2016

Abstract
Water coning is one of the factors restricting the oil development of steam stimulation horizontal wells in highly porous and permeable sandstone reservoirs with bottom water. In order to control water coning and enhance oil recovery, an effective blocking method is described in detail in this paper.
The core of the technology is accurate water exploration with temperature profile and multi slug blocking system. Based on temperature profile and permeability distribution between the target A and B, the water coning is the low temperature section. The multi slug blocking system is comprised of the pre-slug nitrogen, the middle slug conventional gel and the near wellbore blocking slug-the original high temperature resistant plugging agent. The main function of pre slug nitrogen is pushed away bottom water from the near wellbore area. The middle slug conventional gel consists of HPAM and organic cross-linking agent with strong sealing capacity and the applicable temperature under 90°C. It has two functions, one is blocking the temperature lower than 90°C formation, on the other hand is to prevent the backflow of nitrogen. The near wellbore blocking slug is a new low cost and high temperature resistant agent system. The new low cost and high temperature resistant agent system is a solution system without solid particles, which is based on inorganic materials, organic materials as the inducing agent and surfactant as the stabilizer. The viscosity is about 3mPa·s at room temperature. The system began to solidify at 80°C and form the whole solid state finally. The new low cost and high temperature resistant agent system can be able to bear 350°C, and the residual resistance coefficient is as high as 30. The design of slugs is based on the temperature distribution of reservoir.
Since the beginning of 2010, the experimental well has experienced 6 cycles of production, oil production 5300t, cumulative water production 41800t, composite water cut 88.7%. Before water plugging, the cycle oil production is 246t and composite water cut is 96.5% in the 6 cycle. After water plugging, the daily oil production reaches up to 10t from 0.2t and the daily water cut reduces to 50.3% from 99%. The cycle oil production is 1722.7t and composite water cut reduces to 59.7% in the 7 cycle, and the input-output ratio increases to 1:5.
The plugging method can effectively restrain the coning of bottom water and realize reducing water cut and enhancing oil production. It has a very important significance to the development of heavy oil reservoir with bottom water.
Gorgon LNG - Optimising Gas Supply
Authors: Walters Mark 
Published: October 2016

Abstract
The Gorgon project represents a tremendous vote of confidence in the hydrocarbon potential of the Carnarvon Basin, with foundation field resources underpinning a lifecycle of future gas supply projects developing the wider deepwater resource base. With the foundation development costs mostly sunk and production ramping up, investment exposure is at its lifecycle peak and there is intense focus on safe and reliable operations.
However, there is also a need to continue to mature upstream gas supply opportunities. Projects to continue developing the foundation fields are already moving through the planning and development process. Looking beyond those, activities are in progress for selecting the first wave of future gas supply projects and beginning their first steps of development planning.
Distant, deepwater developments carry multiple risks with complex geology, costly and therefore limited data acquisition and record-breaking flow assurance requirements. Long development schedules result in limited ability to respond to uncertainty in foundation subsurface outcomes. Opportunities to maximise lifecycle value include standardisation of "subsea building blocks" and careful planning of new infrastructure to capture geographical and execution synergies.
Chevron and its joint venture participants have invested in an extensive deepwater exploration and appraisal program and are well-positioned to plan for the future. Building a gas supply plan involves a complex combination of portfolio and project principles and processes, drawing upon multiple disciplines and functions in the value chain including exploration and appraisal, early concept project planning, major capital project execution and base business operations.
At this early stage in the Gorgon lifecycle, a pragmatic approach has been taken to deliver effective portfolio planning, providing both the long term view and driving the near term selection decisions for the next wave of supply projects. This paper describes some of the insights and trade-offs being learned and applied in developing the gas supply plan.
Use of Hollow Glass Spheres in Lightweight Cements - Selection Criteria
Authors: Mata Clara , Calubayan Amor 
Published: October 2016

Abstract
Cementing across highly depleted zones and weaker formations requires low density cement systems capable of reducing the hydrostatic pressure of the fluid column during cement placement. If wellbores encounter weak or depleted zones, standard cement cannot be used because the bottom-hole pressure will exceed the pressure gradient and cement will be lost to the formation. Service companies offer cement solutions made light enough to circulate in such situations while retaining the ability to withstand down-hole conditions and maintaining adequate compressive strength to meet regulatory guidelines. Lightweight cements can be achieved using water extension, foamed cement or lightweight microspheres. This paper focuses on the use of lightweight microspheres as density reducing agents. Preliminary experimental data comparing different grades of hollow microspheres is discussed. Cement slurries containing hollow glass spheres and other lightweight hollow microspheres were evaluated while still liquid and after cured. While still liquid the cement slurries were characterized in terms of effective density as a function of pressure. After being cured at room conditions, the resulting cement specimens were characterized in terms of compressive strength. Experimental data suggests that cement compressive strength is mostly independent of the lightweight microsphere strength and strongly dependent on the cement load. Guidelines on the selection of the appropriate microsphere grade are also presented.
Unconventional Resources Exploration and Development in the Northern Territory - Challenges from a Regulator's Perspective
Authors: Rezazadeh M.. , Hattum J. van , Marozzi D.. 
Published: October 2016

Abstract
The production of conventional onshore oil and gas in the Northern Territory began in 1983 from the Palm Valley gas field, Amadeus Basin South of Alice Springs. Up until 2010the industry relied on conventional oil and gas development technology albeit with substantial technological advances over time. In recent years the focus of the industry has shifted to unconventional resource exploration, particularly the highly prospective shale gas resources in the McArthur and Georgina Basins. Current estimates indicate that the Northern Territory has more than 200 trillion cubic feet of prospective unconventional natural gas resources in six basins.
The technologies and techniques to explore and develop petroleum resources from deep shale are innovations on technologies and practices employed for exploration and development of conventional resources with revolutionary consequences, particularly in North America. Those techniques relate to innovations and improvements in horizontal drilling with greater precision and high volume hydraulic fracturing allowing for the development of source rock with extremely low porosity and permeability.
The scale and impact of the unconventional oil and gas industry in North America has led to increased public scrutiny of the oil and gas sector. In particular environmental concerns are being raised regarding contamination of potable water aquifers, sustainable water use and disposal of flowback fluids, induced seismicity, fugitive emissions, well integrity issues and Naturally Occurring Radioactive Materials (NORM) among socio-economic and moral issues. The Northern Territory Department of Mines and Energy (DME) continually adapts its procedures and regulatory framework to maintain effective regulation of the industry.
This paper outlines the key issues that must be addressed from a regulators perspective in regards to the development of an onshore unconventional gas industry in the Northern Territory and DME's approach to regulation and the challenge of maintaining a current legislative framework in a rapidly evolving and highly technical industry sector.
Enhancing Intervention Efficiency and Eliminating Uncertainty — First Ever Successful Conveyance of MWD Tools on CT for Multilateral Well Stimulation in a Middle Eastern Gas Well
Authors: Buenrostro Adrian , Arevalo Alfredo , Alzaid Mustafa , Abulhamayel Nahr , Driweesh Saad , Chacon Alejandro , Fadul Jose Camilo , Noguera Jose 
Published: October 2016

Abstract
Drilling technologies are constantly being developed as operators push the envelope limits to maximize reservoir contact and increase hydrocarbon recovery. These advancements in well construction challenge the well intervention community to seek innovative solutions to successfully intervene in these wells. This paper discusses the successful combination of a slim OD measurement-while-drilling (MWD) tool run on coiled tubing (CT) for real-time survey of the open hole lateral wellbore, followed by a stimulation treatment at appropriate depths for all laterals in a single CT run.
Saudi Arabia has been in the forefront of maximum reservoir contact well construction with the drilling of multilateral open hole gas wells; thus, the need for CT operations to enhance current offerings and procedures. For this application, several tests were performed to determine the feasibility of the combination of necessary tools to be able to steer, identify, and pump the stimulation treatment in a single run. MWD tools were run on CT in this multilateral gas well, and the stimulation treatment was performed during the same CT run.
The common practice in the study area was to run in hole down to total depth (TD) and determine, only by depth difference, in which lateral the CT was located. The uncertainty level increased exponentially when TDs of the laterals were within hundreds of feet because the treatment could potentially be performed in an alternate lateral, rather than the one intended (Ref 1-5). With the use of MWD tools that can relay inclination, azimuth, orientation (steering capacity), pressure and gamma ray, all this uncertainty is eliminated to help ensure a positive lateral identification for proper treatment placement in the well.
The MWD tool run on coiled tubing (CT), implemented a procedure explained in this paper to eliminate the uncertainty associated with previous technologies used for in real-time CT positioning inside the wellbore. The CT position is now reliable verified by survey match with real time readings from CT tip, allowing the certification of job placement in the desired wellbore path, to complete the intervention associated to the CT intervention; i.e.,: "a stimulation treatment" to be done specifically and independently for all laterals in a single run on each. This project open the doors for many other MWD-guided CT interventions to be applied in such conditions.
Justifying Appraisal in a Low Oil Price Environment: A Probabilistic Workflow for Development Planning and Value of Information
Authors: Walters Stuart , Ward Gavin , Wigston Bruce , Talluri Shyam 
Published: October 2016

Abstract
Appraisal adds value to potential developments by changing key development decisions (well count, subsea infrastructure requirements, development sequence, etc.), and this value can be quantified using value of information (VOI). The value of perfect information is readily evaluated but, unfortunately, all real world data is imperfect. Quantifying the value of this imperfect information requires assessment of either (i) the likelihood of the appraisal activity correctly resolving the value of an uncertainty, or (ii) the impact of the activity on the post-appraisal uncertainty range, both of which can be problematic. Traditional value of imperfect information analyses tend to focus on resolving only a single uncertainty and becomes difficult to apply as the number of uncertainties addressed by a single appraisal activity increases.
This paper describes a fit-for-purpose probabilistic approach to enable the rapid evaluation of perfect and imperfect value of information for a range of appraisal alternatives. The workflow is demonstrated through its application to a recent deepwater appraisal well which included an extended well test selected as the preferred activity from amongst a range of alternatives (including conducting no further appraisal).
The workflow uses a Monte Carlo spreadsheet tool to generate gas in place (GIIP) and estimated ultimate recovery (EUR) estimates for individual reservoir elements, which are then aggregated to field level estimates. A large number of individual trial values are captured and interrogated in conjunction with a set of heuristics to allow the rapid generation of probabilistic development plans (without needing to rely on a small set of deterministic realisations). Distributions and dependencies defined in the spreadsheet can be readily altered, enabling robust evaluation of the impact on EUR and preferred development plan for each appraisal alternative and outcome (low/mid/high). The EUR and development plan are then used in an economic model to quantify the value added by each appraisal activity. The highest value appraisal activity, in this case the appraisal well with an extended well test, was executed and a post-appraisal lookback was completed to review the value of information analysis once the appraisal results were available.
Managing Abandonment in Australia
Authors: Askew Philip , Bourdeau Christophe , Volkenborn Arnold , Lea-Cox Andrew , Charan Abhinav 
Published: October 2016

Abstract
Australia is an inexperienced player in field abandonments with early efforts proving complex, high cost, and with last minute approvals due to regulatory and social concerns. Whilst many companies are on top of the costs, they are often isolated from the latest innovations or focused on the next 2-3 years operations. Looking forward, abandonment expenditure will accelerate and be sustained with most companies active and more coming (e.g. Bass Strait, Rankin etc.). Between 2016 and 2030, the overall impact of decommissioning is estimated at $5 billion to $7 billion with the government exposed to up to 60% of this cost through taxes or higher if left with the liability. Considering uncertainty in the regulations, the industry, NOPSEMA and the Government need to deal with what can be left on the sea floor, NORM-related disposals, handling onshore and transfer of liability. Their duty is to protect the environment, provide the platform for safe operations, maximise value for stakeholders but also avoid the taxpayer bearing increased costs/rebates from inefficient programmes. On the cost side, many companies are looking to upgrade abandonment capabilities, and take advantage of new technologies and approaches. However, capabilities and experience are short and regulations unclear. Even so, not all will be equal in their diligence and provisions and hence we are likely to see missed opportunities as an industry. Looking at case studies in Gulf Coast, North Sea and Australia tells us there are many lessons learnt and successes that we should be employing from both environmental and cost angles – e.g. most abandonments struggle with unclear regulations and well/facility deterioration and barrier issues. With these challenges and risks, leadership from all stakeholders should come together to better define and select innovative concepts for decommissioning that moves to sustainable, acceptable and high-value solutions for all stakeholders in the coming years.