bluuebunny/crossref_metadata_2025_split huggingface dataset:
Setting New Records for Drilling the World's Longest Horizontal Well in Basement
Authors: Miguel D. L. , Anh P. L. , Wittry A. , Vernizeau B. , Duy C. , Malpas P. 
Published: October 2015

Abstract
Although worldwide drilling focus is primarily on sand and shale for oil production, a few operators rely heavily on tapping reservoirs basement or volcanic rock reservoirs. In Vietnam, drilling oil and gas in these formations has played a large role in the country's oil and gas activity. The development of technologies might not have reached its peak, but the operating strategies have been continuously tailored to improve the authority for expenditure (AFE) savings.
It has never been proven that drilling a long horizontal &gt;3000-m well section in basement could be efficient and economic. Cost and risks related to the challenges of drilling could easily increase as the basement section lengthens. These challenges include slow drilling time in basement section, numerous bit runs and significant tripping time, high vibration combined with very abrasive formation that quickly causes the bottomhole assembly (BHA) to deteriorate, high applied weight on bit for faster rate of penetration risks the buckling of drillpipes, drilling through massive losses with excessive consumption of brine mud and additives, highly corrosive mud system that affects all steel in the BHA, unpredictable cuttings deposits in the wellbore during losses, lack of available downhole tools to drill the long basement interval, and quick changes of borehole temperature from high temperature to low temperature.
Extensive well planning has always been the key to operational success. The detailed engineering design process involves using an advanced drilling simulation software that comprehends the boundaries/limitations of the surface and downhole equipment. The simulation sets a workable plan to achieve the project objectives safely and efficiently.
Additionally, the basement reservoir's success criteria highly depend on the well passing through productive fracture zones. In the difficult basement conditions in Vietnam, advanced logging-while-drilling (LWD) technology was utilized to accurately detect productive fracture zones, and it helped in optimizing the well completion design. The ability to see and measure the open fractures has aided in the development of better defined and optimized production strategies.
The collaboration of all these aspects has resulted in the drilling of the world's longest horizontal well in basement rocks with proven cost savings for the development of the small and untapped reserves.
Cluster Spacing Optimization Based on a Multi-Fracture Simultaneous Propagation Model
Authors: Lu Qianli , Guo Jianchun , Zhu Haiyan , Zhao Xing 
Published: October 2015

Abstract
Multi-cluster staged fracturing is an effective method to exploit shale gas. Field observations reported some clusters did not generate fractures. X formation in Sichuan Basin is a 3000m deep shale reservoir. The horizontal stress ratio (Shmax/Shmin) is around 1.4 which is therefore difficult to generate fracture network. How to enable all fractures propagate effectively from each cluster and generate enough stress interference to enable fracture network is of critical concern.
This paper established a 2D fracture propagation model based on finite-element method to simulate multi-cluster fracturing. The fracture propagation model couples seepage-stress-damage theories to simulate fracture propagation. The cohesive element is used to simulate the forming of fracture, and the filtration from fracture to matrix is taken into consideration. This model is used to study three fractures propagating simultaneously from three clusters. Different cluster spacing cases were simulated to investigate the fracture geometry and the stress field.
When the cluster spacing is 10m, 20m and 30m, the simulation shows that the length of the middle fracture is severely restricted; but for the side fractures, the length is over propagated. When the cluster spacing is 40m and 50m, balanced propagation of all the three fractures is achieved. In 10m, 20m and 30m cases, the stress field shows that in front of the middle fracture, there is a high compressive stress area caused by over propagated side fractures, and this stress could prevent the middle fracture from propagating. So the range of optimized cluster spacing is reduced to greater than 40m. In order to increase the possibility of generating fracture network, the cluster spacing should be small to create high rock frame stress between the fractures. By considering the fracture geometry and stress field, the optimized cluster spacing is 40m cluster.
This paper presented a method to optimize the cluster spacing by both considering the fracture geometry and stress field. Cluster spacing optimized by this method could enable the effective propagation of all main fractures and increase the possibility of generating fracture network.
Field Development Challenge of Combination Traps in JDA Area of North Malay Basin
Authors: Setiawan A. S. , Rachmadi A. , Simatupang M. H. , Jiraratchwaro C. , Mohd Pushiri M. F. 
Published: October 2015

Abstract
To develop a field with combination structural and stratigraphic trap style is always challenging, especially with trap uncertainties that are coupled with limited exploration and appraisal wells. The potential production shortfall or non cost effective development plan would be an issue if the number and locations of the wells are not carefully selected. Thus, a comprehensive reservoir modeling study, both static and dynamic modeling was designed and instituted to integrate all available information and geological concept.
In the Muda South Central (MSC), which will be discussed further in this paper, structural re-mapping was conducted to refine the trap and structural style. However, the plunging nose structural styles do not have a closing contour to the north of the field, which requires interpretive arbitrary boundary to isolate the compartment and to limit the field boundary. The nearby field in the northern part has a four way dip closure which proves to have a different fluid system with the studied area. Concurrently, a geological facies modeling study was generated using regional trend knowledge and guided by seismic attribute qualitatively. Reservoir trend direction has played an important role in hydrocarbon trapping. The high uncertainty of reservoir presence was assessed by including inputs of low and high extremes sand-shale-ratio in facies modeling exercise for the purpose of capturing reservoir uncertainty.
In dynamic simulation, Simulation Opportunity Index weighted with Gas Initially In Place (GIIP) map is considered to identify sweet spot location. This enables the subsurface team to optimize the number of development well and the placement of the well at the ‘sweet spot's location. Water and sand production prediction is taken into the consideration to minimize the impact to well performance.
Subsurface uncertainty analyses were performed which includes sand distribution, fluid contact in vertical and lateral extension, rock & fluid properties, aquifer strength and well performance. The uncertainty of the number of development wells was anticipated by performing multiple simulations for low and high case. The model is intended to be used as a guidance to subsurface team for decision making during the development drilling campaign.
Inherent Safety Against Cyber Attack for Process Facilities
Authors: McGlone James 
Published: October 2015

Abstract
Process plants, including oil and gas production facilities, need to be protected against physical consequences generated from cyber-attack. While a lot of effort has been placed on securing the computer systems themselves, the design of the facility is often ignored, but is the most important component of the defense against cyber-attack. It is possible to build plants that are inherently safe against cyber-attack by designing in systems and safeguards - such as relief valves and current overload relays - that are not vulnerable to this threat vector.
This paper will review the most common methods for process hazards analysis (PHA) of process industry plants, and then supplement those methods with a "cyber review". The purpose of the cyber review is to determine if there are any cyber-attack vectors that can cause significant physical damage to the facility, and if so, make recommendations for modifying one or more of the safeguards in a cyber-vulnerable vector so that they are not vulnerable to cyber-attack.
The approach that will be discussed includes analysis of the causes of safety incidents, the safeguards that prevent the causes from resulting in consequences, and the magnitude of the consequences that might result from the realization of these hazards. The discussion will include a case study from the oil and gas industry where a Hazards and Operability (HAZOP) study was assessed using a PHA cyber review in order to determine whether or not the facility was inherently cyber-safe, and if not, make recommendations for design modifications that would make the facility cyber-safe.
Feasibility Study of Smart Completion Application in a Complex Mature Field (Dunbar, North Sea)
Authors: Wulandari Tamara , Mazzucchelli Davide , Rasoanaivo Ombana , Zaugg Eric , Olivier Gosselin 
Published: October 2015

Abstract
The Dunbar field is characterized by a high degree of geophysical, geological, and dynamic complexity. Current field recovery factor is 30 %, after 20 years of production. The field is compartmentalised by a number of faults, which subdivide the field into four main areas: the West Flank North, West Flank South, Frontal Central, and Frontal South, with limited to no communication between panels. Permeability degradation with depth is observed in all West Flank and Frontal panel layers, with significant impairment due to alteration of clay morphology, below paleo oil water contact, with a permeability range of only 1-10 mD. Half of Dunbar field's accumulation is located in this poor permeability region, explaining the limited recovery factor. New production technology application is necessary to help improving recovery from this low permeability region.
Passive inflow-control devices (ICDs) and active inflow control valves (ICVs) provide a range of fluid-flow control options that can enhance the reservoir sweep efficiency and increase reserves. Both ICVs and ICDs are capable of equalizing the inflow or outflow into heterogeneous reservoirs. With a more evenly distributed flow profile, one can reduce water or gas coning, and solve other drawdown-related production problems, thus improving the field recovery.
The objective of this study is to evaluate the interest of ICD and ICV application for the coming phase IV drilling campaign. Phase IV infill wells will encounter reservoirs with different levels of depletion and sweep efficiency. Early water breakthrough may become a threat to the success of the campaign. Application of smart completion on a new injector may help optimizing the final recovery on the West Flank panel, intelligent completion providing the availability to selectively steer water injection into zones where it is most needed at a particular time.
First, the phase IV wells are analysed to choose the best candidate for smart completion application leading to retain one horizontal producer and one horizontal injector in West Flank panel The study was performed using a history matched ECLIPSE 300 ® reservoir model of West Flank panel.
The study shows that the installation of ICD or ICV improves the well recovery factor by 10 to 15% and the overall field recovery factor by 1%. The simulation results show that smart completion application in the injector well improves the recovery from poor permeability region by 11 %. An important aspect of the work reported in this paper is also to test the proposed smart completion strategy against uncertainties on reservoir properties. Simulation results show that smart completion is more flexible facing different geological uncertainties.
The US Unconventional Gas Experience - Can the Model be Repeated in Other Countries?
Authors: Chandra V. 
Published: October 2015

Abstract
The US has experienced massive increases in reserves and production of natural gas from unconventional reservoirs. The scale of this increase is unprecedented and is the envy of the rest of the world. Largely as a result of general regional studies by the US Energy Information Agency (EIA) and others similar organizations which promise similar, and in some cases, even higher resource volumes than in the US, many other countries have embarked on unconventional gas exploration efforts.
This presentation will describe the impact of US shale gas and the success factors responsible for its growth. These factors include ‘below ground’ factors such as favourable geologic conditions, presence of natural gas liquids and abundance of well and reservoir data. These factors are, in varying degrees, present in other countries and regions as well.
However, the US also enjoys a number of unique ‘above ground’ factors such as a dynamic service sector, low cost operators, favourable tax and regulatory regime, easy access to pipeline capacity, availability of capital and technology, transparent gas prices, and property rights to land owners. These factors are much harder to find in other countries and regions and are more crucial, it can be argued, for development of unconventional gas than for conventional gas.
Thus, the answer to the question "Can the US model for unconventional gas development be repeated elsewhere?" is unfortunately, "NO". Unless governments and regulatory agencies take strong steps to improve their ‘above ground’ score, it is unlikely that these countries will enjoy the success of unconventional gas development to the same extent as the US.
Innovative Borehole Treatment Utilising Inflatable Packer Straddle System Technology
Authors: Loginov Arthur 
Published: October 2015

Abstract
Open hole fracturing and acid stimulation utilizing the traditional cemented liner and hydro jet perforations or mechanical packers with ball activated frac sleeves have been deployed successfully in the Unites States and Canada for years. One of the primary concerns about the conventional liner methods is assurance of knowing where the fracture or acid is placed. There is no way to determine if there was adequate annular isolation to ensure the planned treatments were placed in the zone of interest.
In an effort to effectively place the fracture in a known location, an inflatable packer straddle system was introduced and utilized to treat the Bakken, Midale, Spearfish and Torquary formations in the southeast Saskatchewan region of Canada. Knowing the location of the fracture provides clarity to understanding the production results. Producing as a barefoot completion may also add incremental production from naturally fractured intervals that may not be exposed to newly-created fractures and also provides flexibility for later interventions or adding laterals.
Improving the procedure, a setting head was developed to drastically reduce time spent between stages reducing water consumption by eliminating the need to drop and displace setting balls to activate the inflatable system at each setting interval. Using this system, the operator can monitor annular pressure in real time to understand when the fracture is starting to break around the upper packer allowing the operator to make adjustments to the fracture treatment of subsequent zones during the job.
This paper will address main considerations of tool operation, case histories highlighting job procedures and lessons learned after several jobs. It will also address use of the straddle system for entering existing wells to re-fracture the formations to improve production and extend the life of the well.
Risk Analysis Significantly Reduces Drilling Project Costs: Vital in the New Oil Price Era
Authors: Gibson M. , Pawlewski M. 
Published: October 2015

Abstract
This paper portrays how drilling project costs can be reduced significantly, through the use of Risk Impact Amalysis, which is vital in the current era of unprecedently low oil prices which puts pressure on the whole chain of oil and gas services.
New ways of thinking and inventiveness are required if we are to keep drilling as opposed to stacking rigs which is happening at an alarming rate particularly on land in the U.S.A. If the cost of drilling cannot be reduced further, rigs will be stacked, several "cold" and the lucky ones "warm’.
This paper desrbibes how, through focused risk anaylsis, a 10,000 rated rig was allowed by the authoriesto drill as opposed to the more normally required 15,000 psi requirement.
A Cable-Controlled Separate-Layer Production Technology
Authors: Yuning Wang , Xin Wang , Meng Cai , Renyong Liu , Qingfeng Yue , Qinghai Yang 
Published: October 2015

Abstract
In high water cut oilfield, the separate-layer producers often face the problems of low separate-layer control level, difficult water locating and plugging, high operation cost and low testing and adjusting efficiency. As to solve these problems, new separate-layer production technology is required. The paper proposes a cable-controlled separate-layer production technology. The cable-controlled separate-layer production system consists of adjustable production regulator, testing and adjusting instrument, ground controller, and some matching tools. In the operation process, the testing and adjusting instrument is run into the wellbore through cable. The locator of the instrument can fix the accurate position where the target regulator is. After the delivery of the instrument, the testing and adjusting instrument connects with the adjustable production regulator. The liquid flow rate of the regulator can be adjusted continuously according to the instructions and the flow rate can be read simultaneously on the ground. The pressure and water cut of the single layer can also be monitored. Once the testing and adjusting of the target regulator are accomplished, the instrument disconnects with the regulator and move on to the next layer under the command from the ground. Field tests showed that the technology realized production adjusting and parameter testing of each layer in the producers. This technology requires the producers to possess well-preserved casing tube and annular testing condition. The technology is applicable to the rod pumped wells with big water cut variation, and the important wells whose reservoir need to be specially monitored. Because the testing and adjusting instrument is run into wellbore through annulus, the operation can be implemented while the pump unit is working, without interfering normal production. The cable-controlled separate-layer production technology effectively relieves the planar, inter layer and interior layer production contradictions. The balanced production of all kinds of reservoirs is realized and the producing capacity of medium-low permeability reservoirs is released, improving production rate and oil recovery.
Failure to Success to Hydraulically-Fracture-Stimulate a Low Permeability Oil Sand in Sumatra, Indonesia
Authors: W Faizal Ardi , Maryono Dedi , Prakoso Ambaria , Hezmela Rizka , Tsangueu Barbara 
Published: October 2015

Abstract
DC-15 is one of 17 oil production wells in the Kuat oil field in the Malacca Strait PSC, Sumatra, Indonesia. The reservoir is in the Lower Pematang Sandstone (6699 – 7015 ft.), which is a massive sandstone 281 ft. thick, with porosity of 11-14%, permeability of 2-10 mD, and water saturation above the 100 ft. transition zone of 20-30%
The reservoir is normally-pressured at 2200 psi, but has a high temperature gradient of 5.2 degF/110 ft., so the reservoir temperature can reach 325 degF
This paper tells the story of fraccing the DC-15 oil development well, which transformed the well from commercial failure in 2009 to commercial success in 2013, and covers perforation strategy, fluid recipes, proppant selection and frac operations. Improved frac design by applying lessons from the first frac job led to successful placement of the frac. The frac managed to increase the oil rate from 38 bopd to 168 bopd and increase the expected oil recovery from 53 mstb to 147 mstb, turning a likely money-losing well into a confirmed money-making well.The main changes were: Changing the perforation density from 5 spf to 12 spf helped to reduce the friction pressure during treatment allowing the frac to be placed at higher rate with lower surface pressure and reduced risk of screen out.Changing the frac fluid from conventional polymer fluid with zirconate-crosslinked fluid to the newly improved high temperature fluid that allows 5 lb./1000gal less polymer and has lower friction pressure hence the pump rate could be increased from 13 BPM to 20 BPM;Changing the proppant from 12/18 and 20/40 Intermediate Strength Proppant (ISP) to 16/30 High Strength Proppant (HSP) mitigated against crushed proppant production, which allowed the well to be produced at its full capacity.Adding fiber based proppant flowback control agent in the last proppant stage was successful to avoid proppant flowback.
Unconventional Radioactive Source Retrieval Inside LWD in Horizontal Well
Authors: Permana A. Aziz , Pramukti Cahya Dadiyanto , Wahyudi Danar Aji , Reza Rama Aditya , Moehidin Moehidin , Setiawan Adjie 
Published: October 2015

Abstract
Horizontal drilling is one of development strategies to optimize the oil recovery, especially in a mature field. Horizontal well can reduce water and gas coning and prevent the pressure drop around the well bore, therefore the oil recovery can be increased.
Radioactive source in Logging While Drilling (LWD) tools is used for X-42 horizontal drilling well but stuck problem that occurs during the drilling operation can be caused by differential sticking or failure hole cleaning. High angle inclination in horizontal well certainly increases the difficulty of retrieval job.
As a company regulation, the radioactive source should be retrieved before continuing the efforts to free the drill string. The wireline has agreed to help the radioactive retrieval but this operation should be done in 81° of inclination. Then, it will need a thrusting force to facilitate the bottomward movement of the assembly. Two attempts of retrieval with wireline are made before they bring up the idea of using sucker rod as the replacement a wireline cable.
This paper explains how the unconventional radioactive retrieval method with sucker rod as the alternative of wireline is more reliable to retrieve the radioactive fish especially in horizontal wellbore which technically has a very high inclination and 3D profile which the tool need a thrusting force to push the fishing tool assembly to the bottom.