bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Hod Geohazard: A Unique Overpressured Interval—Cooperation in Its Recognition, Evaluation, and Risk Mitigation
Authors: Holm G. , Owens J. , Page G. , Ritchie A. 
Published: December 2007

Abstract
While drilling wells in the Total operated Franklin, Elgin and Shell operated Shearwater HPHT fields of the UK central North Sea, gas was often encountered over intervals in the Upper Cretaceous Hod Formation. In addition, gas continued to bleed occasionally into the well until the section TD. During the completion phase of a Franklin well, the annulus pressure started to rise and a temperature and gamma ray survey indicated that fluid was bleeding into the annulus from a thin zone within the Hod Formation. Given the common issues, the so-called "Hod Geohazard" was identified for further shared study between the two operators.
Open hole logs over the Hod Formation for three of the Franklin wells were used to quantify the hydrocarbon in this interval. Three thin limestone horizons were recognised from a review of the drilling gas and cased hole gamma ray and acoustic data. An overlay technique was applied to the gamma ray and acoustic logs, which showed that two of the limestones were tight, but the third, three meters thick, had apparent porosity.
The overlay technique was then applied to the development wells, where only gamma ray and acoustic data were available. This allowed a qualitative estimation of the degree of porosity and permeability for those wells. The results indicated that the three limestone horizons had a regional distribution, although with varying degrees of porosity. This then provided a predictive tool to assess which wells were likely to have live annuli when turned over to production.
Identification of this Geohazard as a tight, overpressured gas bearing horizon has been important. It was realised that cemented casing was unlikely to hold this gas back during the production lifecycle of the wells. Consequently, casing annulus pressure management systems were installed on the facilities. In addition, increased awareness of Hod gas influx during drilling was included in the planning of subsequent wells in the region.
The key to these improvements was the collaboration of operators sharing experiences. It resulted in improved drilling and completion practices for both companies during their projects. The lessons learned can be applied by other operators in similar challenging HPHT environments.
Non-Darcy Flow in Hydraulic Fractures: Does It Really Matter?
Authors: Miskimins J. L. , Lopez-Hernandez H. D. , Barree R. D. 
Published: December 2007

Abstract
In recent years, non-Darcy flow has seen a significant increase in interest in the petroleum industry, especially in flow in fractures—both artificial and natural. In hydraulic fracture stimulation, non-Darcy flow can have a major impact on the reduction of a propped half-length to a considerably shorter "effective" half-length, thus lowering the well's productive capability and overall reserve recovery. These non-Darcy flow effects in propped fractures have been typically associated with high flow rates in both oil and gas wells.
This paper shows that non-Darcy flow effects have an impact on the performance of a hydraulically fractured well even at low flow rates. Although not as drastic as the effects on high flow rate wells, reductions in flow capacity of 5-30% can be realized in low rate wells. Such reductions are due solely to non-Darcy effects. When combined with other concerns, such as multiphase flow, the production reduction effects are even greater.
Development of a simple spreadsheet is provided to aid engineers in assessing the impact non-Darcy flow may have in a given situation. The spreadsheet is not intended to replace more in-depth investigation of non-Darcy flow effects but instead provides a conduit to assess the sensitivity of certain parameters in a hydraulic fracture stimulation situation.
For comparison purposes, results of the loss in long-term dynamic conductivity on well performance and cumulative gas recovery over time in low permeability reservoirs are also presented. These calculations were performed using dynamic conductivity loss calculations coupled with a transient gas reservoir simulator. These results showed that for the cases examined, non-Darcy effects could reduce cumulative gas production by up to 18.1% over a ten-year period.
Numerical Investigation of Horizontal Well Performance with Selective Completion
Authors: Kalita R. , Jalali Y. 
Published: December 2007

Abstract
This study presents a numerical method of determining the sandface completion profile of a horizontal well to achieve a prescribed production objective. A technique is developed to determine the completion profile that maximizes an objective function (e.g., cumulative production) for a given well operating program in a defined reservoir environment. Sandface completion is modeled in terms of a connection factor between the reservoir gridblocks adjacent to the well and wellbore segments. Well performance is evaluated in terms of cumulative production within specified operational constraints (maximum rate, minimum bottomhole pressure). The method uses a finite-difference technique to determine the sensitivity of well performance to changes in the wellbore-reservoir connection profile. The optimum connection profile is determined by a gradient-based technique using the sensitivity coefficients from the finite-difference method. This approach can be used to either plan the sandface completion during the well design stage, or to optimize the completion after drilling based on measured petrophysical and flow properties of the formation. Examples are given in the paper covering both water-and gas-drive problems.
Improved Reservoir Management Through Integration Of 4D Seismic Interpretation, Draugen Field, Norway
Authors: Mikkelsen P. L. , Guderian K. , du Plessis G. 
Published: December 2007

Abstract
4D seismic interpretation plays a key role in the reservoir management of the Draugen Field, situated offshore Norway. Time lapse seismic surveys of exceptional quality conducted in 1990, 1998, 2001 and 2004 have all shown outstanding areal and vertical definition of the water movement towards the producing wells.
Excellent reservoir properties with relatively few high rate wells and an expected recovery factor exceeding 60 percent make Draugen one of the best performing fields offshore Norway. The field has a simple geology, however, the reservoir structure is relatively uncertain due to the low number of well penetrations for calibrating the structure. Fortunately, the 4D seismic interpretations have largely compensated for this shortcoming by providing improved lateral control for refining the reservoir simulation models.
All of the 4D interpretations conducted so far have indicated the need for simulation model changes such as modified reservoir volumes in certain areas, revised fault transmissibilities, and the need for improved relative permeability characteristics. Integration of the 4D interpretation results has greatly improved the various Draugen reservoir simulation models enabling improved forecast and reserve estimates as well as better business decisions. Effects on the field reservoir management have included revising the water injection strategy, converting a producer to injector, re-positioning a development well and drilling an appraisal well.
Offshore Implementation Of Through-Tubing Dynamic Annulus Pressure Controlled (DAPC) Coiled-Tubing Drilling
Authors: Laird A. , McFadzean K. , Edgar J. , Harty I. 
Published: December 2007

Abstract
Dynamic Annular Pressure Control (DAPC) is a new technology that allows accurate control of downhole pressure in a well. DAPC was used in conjunction with Coiled Tubing Drilling (CTD) on the Gannet GA-03 well between February and April 2005. This report describes the selection, design, testing and field performance of the recent DAPC-CTD Gannet project.
The original horizontal wells in the Gannet Alpha reservoir were positioned in the middle of the 53ft oil rim. Upward migration of the oil rim, due to gas production, meant that it had moved beyond the reach of the original horizontal wells. As a result, these had watered out, and many of the wells had been shut in for several years.
A review of the reservoir model in 2000 revealed that much of the migrated oil, some 25-35% of the STOIIP, was stranded and would be lost forever unless infill drilling was performed.
Re-instatement of the drilling rig was considered uneconomic and CTD was selected as a lower cost, technically feasible option, though Shell's history with CTD showed mixed success, indeed a five well campaign in 1999 was cancelled after catastrophic failures in the first two wells. The primary issue in these wells was associated with managing the downhole pressure to find a balance between wellbore stability and differential sticking. The main subsurface challenges on the Gannet are the same and as such overcoming these hurdles was of prime importance.
CTD and DAPC offered a novel solution, and this report details the development of the Gannet CTD project through feasibility, concept selection, detailed design, and successful execution.
Tuning an Equation of State—The Critical Importance of Correctly Grouping Composition Into Pseudocomponents
Authors: Al-Meshari A. A. , Zurita R. A. A. , McCain W. D. 
Published: December 2007

Abstract
A limited number of multiple carbon number groups are used in compositional simulation to represent the heptanes plus fraction of the petroleum mixture. The selection of the single carbon number groups that are grouped into the multiple carbon number groups has a severe effect on the calculation of the position of the critical point of the mixture. This in turn strongly affects the maximum constant volume line of the phase diagram at reservoir temperature. If the maximum liquid volume at reservoir temperature is nearly correct then the match of other pressure-volume-temperature data of a laboratory study is relatively simple. A correlation has been developed to determine the correct grouping of the multiple carbon number groups. Also it was found that only two multiple carbon number groups are required to represent the heptanes plus fraction of a petroleum mixture.
Gas Management, Reservoir Surveillance, and Smart Wells—An Integrated Solution for the Bugan Field
Authors: Dolle N. , Singh P. , Turner R. , Woodward M. , Paino W. -F. 
Published: December 2007

Proposal
This paper describes a study to investigate the preferred gas management strategy, the required reservoir surveillance program and the enabling well completions to provide an integrated solution for the optimum development of the Bugan Main Block.
The main drive mechanism for the Main Block reservoirs is a combination of solution gas drive and gas cap drive. Conservation of reservoir energy, through controlled gas production, is crucial to maximize reserves. This is undertaken by the creation of a Gas Management Strategy (GMS) aimed at maximizing the ultimate recovery of oil through control of the reservoir GORs.
In reality, the ideal gas management strategy, in terms of initial GOR plateau and ramp-up schedule, depends on the actual reservoir performance. Value of Information studies indicate that reservoir surveillance is required to capture both potential up and downsides in terms of available reservoir energy. This surveillance would allow the adjustment of the gas management strategy to maximize value and safeguard reserves.
Smart completions with inflow control valves (ICVs) and down hole pressure gauges (DHPGs) meet the surveillance requirements and the initial expenditure has been compared with lifecycle costs of conventional CTU well interventions. It is concluded that running a smart completion is preferred over a conventional completion, because of lower lifecycle costs, improved well and reservoir surveillance, lower operational risks and reduced production deferment.
Substance Abuse Testing Program: A 10-Year Experience
Authors: Khantong A. 
Published: December 2007

Abstract
To ensure the safety of the workplace and employees, Unocal Thailand established a Substance Abuse Policy in 1994. The testing program employs random and mandatory selection procedures to deter individuals from using prohibited substances. Both urine tests and breath tests are administered. The program has been challenged several times by employees with various allegations, including violation of privacy, breech of terms of employment, the validity of the test, and overall legitimacy of the process. Because of its open, transparent and constructive approach, the program has over time become accepted as an effective safety measure for living and working together. The program has been regularly updated to ensure that procedures and testing methods are performed consistently and fairly, without losing the primary objective of deterrence.
Use of Pressure-Activated Sealant to Cure Leaks in Subsea Wells—A Case Study in Campos Basin
Authors: Rodrigues V. F. , Gonçalves G. G. , Rusch D. W. , Videira J. L. 
Published: December 2007

Abstract
Offshore oil and gas production systems are complex systems comprised of wells, flow lines, a variety of subsea and dry subsystems, production platforms and export lines. Hydraulic systems are extensively used in offshore production systems, particularly for valves control and operation. Failures in hydraulics systems may cause loss of redundancy, loss of control and well shut-in with economic losses and risks to system integrity and environment. Leaks, mostly internal, represent one of the most common failures in the hydraulic systems. The conventional approach to repair these leaks makes use of rig and/or support vessels, being time and money consuming, not mentioning the risks imposed to the system under intervention. The difficulty, risks and costs increase with water depth. In the Campos Basin, offshore Brazil, with around 500 subsea wells, in water depths range from shallow to ultra deep, leaks in hydraulic systems have a significant impact on maintenance costs. Sensitive components are down-hole safety valves, wet christmas trees valves, annulus subsurface safety valves and subsea manifolds subsystems. These aspects made the search for reliable remote or light workover solutions an important issue. A promising solution was introduced in Campos Basin in the year 2000, which makes use of a pressure-activated sealant fluid. This paper presents a case study comprised of tens of pressure-activated sealant applications, both in fixed and floating systems, carried out in Campos Basin in the last four years. The paper summarizes the operational programs, the field reports, the post-job analyses and the results achieved. The study revealed that pressure-activated sealants are a safe and economic method to repair leaks in offshore hydraulic systems. As the number of offshore oil and gas production systems, mainly the floating ones, tends to increase considerably in the near future, the knowledge acquired in Campos Basin may be useful worldwide. The main differential of this paper is a thorough and critical review, from the operator point of view, of 71 applications from 01/21/2000 to 05/16/2005.
Life Beneath the Platforms—The Movie …
Authors: Holyoak S. , Munns R. , Oldfield M. 
Published: December 2007

Proposal
A supporting paper (Ref. 1) describes the results of the Platform Environmental Project, aimed at documenting and understanding the diverse ecosystem associated with the oil and gas production platforms, offshore Belait, Brunei Darussalam.
In order to demonstrate the development and diversity of the species present, a 20-minute documentary has been made. This captures the colour and dynamics of the marine life in a way that is not possible via written documentation alone. The DVD-based film is therefore seen as an excellent tool to increase the awareness of the platform ecosystem amongst stakeholders and other interested parties.
By showing this film at the conference we aim to highlight another angle of the environmental impact of the oil and gas industry, one that should be a key part of any future discussions regarding decommissioning options in the region.
Health, Safety and Environment Culture in the Norwegian Petroleum Industry
Authors: Høivik D. 
Published: December 2007

Abstract
During the last few years there has been increased focus on Health, Safety and Environment (HSE) Culture in the Petroleum industry in Norway. The concept of HSE culture can be understood in different ways and on different levels. This study concludes that a holistic, systemic way of understanding HSE culture gives an opportunity both for understanding and for taking appropriate actions for HSE.
Removing Mercury from the Workplace: A Case History of the Decommissioning and Recycling of Mercury-Contaminated Equipment
Authors: Berdugo V. , Bjoroy R. , Richards C. J. , MacWilliam D. , Riding M. , Ross B. 
Published: December 2007

Abstract
A project was undertaken by the company to locate, quantify, and remove all mercury-contaminated equipment and elemental mercury from its global network of field and laboratory operational locations. The equipment and elemental mercury was shipped to prequalified vendors for equipment decontamination, mercury recovery, and purification with the aim of recycling the recovered mercury and decontaminated materials back into use.
Malaria Control Measures for Oil and Gas Operations – What Works – What Doesn't – What Does the Literature Say?
Authors: Balge M. Z. , Krieger G. R. 
Published: December 2007

Abstract
Exploration and Production projects can potentially create adverse health impacts for workers and surrounding communities unless appropriate malaria control programs are designed, implemented and monitored on an ongoing basis. These company based control programs often contain measures that often are not evidence-based and that may actually impair community malaria control efforts.
This paper will present strategies and tools for use in developing effective malaria prevention and control programs through reviewing the current literature regarding: Malaria educationBite prevention and vector controlChemoprophylaxisDiagnosis and treatment
These strategies can result in cost effective mitigation of potential adverse health impacts by implementing scientifically based programs developed for the specific malaria risk in the defined geographic area.
Environmental Management for Thai Offshore Base Construction Project
Authors: Lambasara D. , Soponkanabhorn T. 
Published: December 2007

Abstract
PTTEP's Thai Offshore Base (TOB) has been under construction since 2002. Several potential environmental impacts include fish farming, ground vibration, potential shoreline erosions and excessive noises were encountered. To this, PTTEP took new initiatives in implementing series of environmental management into the project in order to solve any profound impacts to environment claimed to have occurred and to the nearby communities. PTTEP had set up a so-called Environmental Impact Monitoring Committee chaired by Sonkhla Provincial Deputy Governor which was comprised of representatives from provincial governments and local agencies, representatives from the local residents in community and the project owner to continuously observe changes and any environmental impacts occurred. The Environmental Impact Monitoring Committee meetings were held on regular basis to solve any problems resulted from the project. Moreover, series of other environmental management initiatives were also implemented throughout the construction period such as the use of silt curtains. PTTEP installed the silt curtains around the dredging sites to prevent outflow of silts. It was the first large and systematic silt curtains ever installed in Thailand for dredging sites. Series of other environmental management works were implemented such as routine and regular environmental quality monitoring of seawater, air, noise, etc, and conducting a PostEnvironmental Impact Assessment (EIA) for any changes in designs which occurred.
PTTEP's environmental management initiatives on TOB project has proved to be efficiently implemented without any major protests, unlike other projects during that time. Experiences gained from this project have been successfully applied to other project such as the major gas pipeline in the southern Thailand.
An Evaluation of Well Completion Impacts on the Performance of Horizontal and Multilateral Wells
Authors: Ouyang L. -B. , Huang B. 
Published: December 2007

Abstract
Well completion plays a critical role in well design, and more importantly, the performance of the well in its entire life. The major objective for this study is to provide some guidance in the design of completion configuration by a series of simulation with different completions under different flow and reservoir environments. The reservoir inflow and the wellbore hydraulics under complex completion environment will be fully coupled in the study. The most popular completion options, including open hole, slotted liner, inflow control devices (ICD), intelligent well completions (DIACS), perforated cemented liner, wire wrapped screen, ECPs, gravel pack, and frac pack, will first be briefly introduced and reviewed. The performance of the completions will be explored and compared for different wells under different flow conditions, including fluid type, well type, well rate, pressure drawdown, and reservoir geology.
Well performance will then be studied in details by evaluating the total well production, annular flow and flow inside the liner/tubing, pressure profiles along the annulus and along the liner, inflow from reservoir to annulus and fluid transfer between annulus and liner, and so on. Impacts of key parameters like skin factor, wellbore length, well completion configuration, and pressure drawdown, will be investigated.
Implementation of Slurry Fracture Injection Technology for E&P Wastes at Duri Oilfield
Authors: Arfie M. , Marika E. , Purbodiningrat E. S. , Woodard H. A. 
Published: December 2007

Abstract
The Duri oilfield is one of the 141 oil fields operated in Sumatra, Indonesia by PT Caltex Pacific Indonesia under a production sharing contract with the Government of Indonesia. Discovered in 1941, the Duri field is one of the world's giant oilfields and the biggest steamflood operation located in the Rokan block with current oil production of 200,000 bpd (31,000 m3 per day). The insitu formations of the Duri field are unconsolidated sands; coupled with a steam flood operation they are susceptible to producing large quantities of oily viscous fluids as a by-product from the oil production. Up to 400 m3/day (2,500 bpd) of oily viscous fluids are generated at five oil production Central Gathering Stations (CGS) in the Duri oilfield.
Slurry Fracture Injection™ (SFI™) is an environmentally viable deep well disposal process for Exploration and Production (E&P) waste streams. The SFI process can be used in the petroleum industry to dispose of produced solids, oily viscous fluids/sludges, tank bottoms, contaminated soils and drill cuttings.
There are a number of environmental advantages associated with the SFI process that make it suitable for E&P waste management strategies that include: permanent disposal of waste materials, zero surface discharge, no adverse interaction with the environment, reduced risk of ground water contamination, and relatively low cost. The SFI process was determined to be the most environmentally viable process for E&P waste management at the Duri oilfield in Sumatra. This SFI project represents the first time that the SFI process was implemented in Indonesia. This paper details the SFI project assessment, development, and field operations related to this deep well disposal process at Duri.