bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overview of Exploration for Petroleum in Malaysia under the Production-Sharing Contracts
Authors: Said Ahmad 
Published: December 2007

Abstract
The paper discusses the exploration efforts and successes achieved in Malaysia under production" sharing contracts in the 5-year period from 1977-1981.
At the end of 1976, PETRONAS signed 5 production-sharing contracts with SHELL and ESSO for areas offshore Sabah, Sarawak and Peninsular Malaysia. In the 5-year period, over 52,900 line-km of seismic were acquired and 202 exploratory and appraisal wells drilled, resulting in 45 new hydrocarbons finds of significance.
Most of the oil and gas finds were made in the Tertiary sediments of the Malay Basin which had been relatively unexplored prior to 1977. 03 and gas finds were also made in the relatively more mature and geologically more complex exploration provinces of Sabah and Sarawak. The J4 discovery in Sarawak opened up a new precarbonate exploration play in the Central and SW Luconia and NW Balingian Provinces.
The high level of exploration activity has resulted in a substantial increase in Malaysia's remaining petroleum reserves. The 5-year period has also seen the emergence of the Malay Basin, offshore Trengganu as the most prolific hydrocarbon province in Malaysia to date.
Future Hydrocarbon Prospects in Afghanistan
Authors: Tate Robert B. 
Published: December 2007

Abstract
The geology of Afghanistan is described in relation to hydrocarbon occurrence and future potential. Current gas production, exported to Russia, is abstracted from structural closures in Cretaceous — Neogene sediments on the margin of a Neogene — Recent depression northwest of the Hindu Kush mountain range. Source rocks are thought to be Jurassic paralic sediments and/or Cretaceous platform limestones, the latter outcropping extensively across much of central Afghanistan north of the Herat fault zone, a major fracture separating two tectonically different regions. Future exploration should be directed towards the search for similar structural closures with other Neogene — Recent depressions bordering the Hindu Kush, particularly in the north and west.
Substantial thicknesses of Mesozok and Paieogene clastic and calcareous successions are reported to occur in the southern part of the Katawaz fault block, a geotectonic unit between two major fracture zones in SE Afghanistan. Aeromagnetic and field studies indicate a basin up to 9000m thick containing suitable source and reservoir rocks but tight folding, lack of seal lithologies and excessive depth of erosion lessen the chances of finding hydrocarbon pay zones.
Future discoveries are more likely to be gas than oil as the geothermal gradient, both present and historis is thought to be high in view of the tectonic position within a collision zone. Nevertheless, oil seeps, bitumen and fetid limestone in central and western Afghanistan suggest dissociation may not be complete.
Compressible Cement Slurry Helps Solve Annular Gas Flow
Authors: Ott William K. , Miller Gene Warren , Sutton David L. 
Published: December 2007

Abstract
Annular gas flow following cement has been a problem in many areas throughout South-East Asia. In some offshore fields, gas migration occurs on surface, intermediate and production casings and liners. This phenomenon gives rise to gas pressure on the annulus between casings or even interzone communications. Both can cause costly remedial repair work and unpredicted high volume flow to the surface has on occasions caused catastrophic disasters.
Laboratory testing and field applications in many areas of the world have shown compressible cement slurries to possibly be the most effective means of helping to prevent annular gas flow developed thus far. This paper will review the development and application of compressible cement slurries.
Over 800 compressible cement slurry applications have been run throughout the world and the success ratio is greater than 90%. Applying this technique on a more wide-spread basis may possibly reduce the many problems associated with annular gas flow in South-East Asia.
Tubing Buckling Analysis With Expansion Joints
Authors: Mitchell Robert F. 
Published: December 2007

Abstract
A new type of tubing completion in use in the North Sea is a fixed packer with an expansion joint several joints upstream of the packer. The expansion joint installation may be either pinned closed, or sheared and spaced out after packer installation. The joint may or may not have a stop to prevent jump-out. If the joint is pinned close, then a shear rating must be specified for the shear pins. Additional information necessary for expansion joint analysis includes the joint stroke length, joint seal bore diameter, and installation space out, if sheared.
There are distinct differences in the analysis of expansion joints compared with conventional packer installations. This paper details the tubing movement and stress calculations for both pinned and sheared expansion joints. The pinned joint is designed to fail at a specified tubing load, either compressive or tensile. After pin shear, the tubing has free movement until the joint closes, jumps-out, or is restrained by a stop. The sheared joint movement calculation is distinct from conventional tubing movement calculations because there are two piston loads, instead of only one in a free packer. The tubing below and above the joint may buckle. Bending as a result of buckling may cause binding and friction loads in the expansion joint.
This paper presents several example cases that give insight into the potential benefits and problems of expansion joints in comparison with conventional tubing completions.
A Systematic Approach to Drilling and Delivering Wells in Severely Depleted Sands at Ram Powell (GOM)
Authors: Algu D. R. , van Oort E. , Landgrave S. , Grant L. , Hillburn D. 
Published: December 2007

AbstractRe-development drilling at Shell's Ram Powell prospect in the Gulf of Mexico targets profitable delivery of remaining hydrocarbons present in lower-volume reservoir pockets. Marginal economics put a strong focus on efficient operations, which are complicated by the technical challenges posed by severely depleted reservoirs (up to 6,000 psi differential pressure) that can only be accessed by drilling extended reach (ERD) wells. Specific challenges that had to be overcome in drilling recent Ram Powell wells include negotiating very narrow drilling margins, preventing major non-productive time associated with well control, lost circulation and stuck pipe events, and drilling the wells at optimum efficiency and favorable economics.This paper discusses the integrated operational plan that the Ram Powell team employed to successfully drill four recent ERD development wells and two slim hole sidetracks through substantial depletion while becoming one of the best-performing offshore operational teams in Shell. Specific tactics discussed include: (1) a fit-for-purpose hole cleaning program for ERD and depleted wells; (2) a mud weight and ECD strategy that exploits the naturally existing stress cage; (3) an effective method to raise fracture propagation pressures in case of losses in induced or natural fractures; (4) the use of flat-rheology synthetic-based mud to minimize barite sag and reduce ECDs; (5) addressing the underestimated effects of temperature, annular pressure fluctuations and exposure time on wellbore stability and lost circulation; (6) contingencies to deal with well control issues during a catastrophic loss; (7) dealing with detrimental vibrations during depleted sand drilling
The Application of Expandable Tubulars in Casing While Drilling
Authors: Gupta Yash , Banerjee Sudeepto N. 
Published: December 2007

Abstract
The idea of drilling single diameter wells has been debated for a number of years. And in recent years, the dream of mono-bore wells is taking form thanks to the development of new technologies. The use of expandable tubulars and the drilling with casing system are the most favoured processes.
This paper discusses the possibility of coagulating these two technologies in an attempt to achieve maximum economic and productive efficiency. The system consists of the usual assembly for drilling with casing, which uses the top drive mechanism, and an expansion cone (mandrel) installed above the drill lock assembly. The expansion cone is operated from the surface through the rotary table. The operation involves drilling to the casing depth using the drilling with casing assembly, and then bringing the expanding cone into action. The expansion procedure starts by conditioning the string and pumping in the expanding fluid through the expansion mandrel. It is caught in the area between the mandrel and the drill lock assembly by closing the bypass valves in the latter. Thus the pipe joints above the drill lock assembly are expanded by the normal procedure, till the mandrel reaches the surface. The mandrel is pulled out, and subsequently the drilling with casing BHA is retrieved by a wireline.
This procedure makes use of the economic savings achieved in case of drilling with casing and the productive maximisation which is achieved for expandable tubulars. By using the expandable tubulars at shallow depths, more casing strings can be accommodated resulting in production of deep formation(s). This procedure also involves a reduction in time related to tripping operations which was earlier associated with the drill string assembly.
More importantly this new technology finds it major application in extended reach deep water drilling, where ultraslim wells need to be drilled to reach the formation. This technology requires a class three or four drilling vessel instead of a conventional class five vessel, thus reducing the drilling costs substantially. These two technologies are currently being used in independent fields and there is no published evidence about the combination of these two operations. Now as this method is researched further, new and more improved versions of the same can be developed.
Applying Risk Analysis to Casing While Drilling
Authors: Houtchens B. , Foster J. , Tessari R. 
Published: December 2007

Abstract
Engineers and managers make decisions related to drilling operations every day that must balance the risk of various alternatives. These decisions may be based on a mental, experienced based risk model that has been developed over years of decision making. However, many companies are moving to explicit risk models where risk and its economic impact are quantified. Risk is composed of two components: the probability of an event occurring and the economic consequences if it occurs. This modeling uses a logical progression to predict economic impact of trouble events such as well control, loss of circulation and sticking of the drill string or casing string.
Applying a risk model to new technology is difficult because there is no experience base for quantifying either the probability of an event occurring or the consequences of the event. This is particularly true when the technology has operational components that go against normal practices. Such is true with Casing while Drilling. Casing is used as the drill string to solve problems that one would normally expect to be made worse by drilling with a smaller wellbore clearance, higher annular velocity, and little ability to make conditioning trips.
This paper will show the results of more than 280 wells and over two million feet of hole drilled with casing over the last eight years. Comparisons will be made to conventional drilling methods in several of the areas where the technology has been applied. Elements of study include casing fatigue, casing wear, tool reliability, underreamer durability and reliability, differential sticking, lost circulation induced by increased ECD, acceptable penetration rates, etc. Results of these wells in difficult drilling areas show positively that drilling with casing is more efficient and encounters less trouble time than conventional drilling, saving operators both time and money. These savings can be seen in daily operating costs, personnel safety and in insurance premiums for the operators and drilling contractors.
Drilling, Completion, and Openhole Formation Evaluation of High-Angle Wells in High-Density Cesium Formate Brine: The Kvitebjørn Experience, 2004–2006
Authors: Berg Per Cato , Pedersen Erik Sandtorv , Lauritsen Åshild , Behjat Nader , Hagerup-Jenssen Siri , Howard Siv , Olsvik Gunnar , Downs John D. , Harris Mike , Turner Jim 
Published: December 2007

Abstract
Drilling and completion fluids based on cesium formate brines were selected by Statoil for use in the development of the high pressure high temperature Kvitebj0rn field. Cesium formate brine was selected primarily to minimize well control problems and maximize well productivity. These important benefits had been recognized by Statoil in previous HPHT drilling and completion operations over the past 5 years. The use of the same fluid system for both drilling and completion gives the additional benefits of simplified operations, reduced waste, and elimination of fluid incompatibility problems.
The challenge on the Kvitebj0rn field was to drill long deviated well paths through significant sequences of shales into reservoirs with pressures of up to 81 MPa (11,700 psi) and temperatures up to 155°C (311°F). So far the cesium formate brine has enabled the successful drilling, completion, and logging of 7 high angle HPHT production wells on Kvitebjørn, two completed with a cemented perforated liner and five with sand screens.
Additionally, an extended-reach exploration well was drilled from the Kvitebjørn platform to the Valemon structure. The 705 m (2,313 ft) long reservoir section of this 7,380 m (24,213 ft) long well with an inclination of 69°, was successfully drilled with the same cesium formate fluid system.
In all these wells the cesium formate brine system once again demonstrated clear performance benefits such as very low ECDs, moderate to high ROPs, good hole-cleaning, and excellent wellbore stability while logging. Quick, trouble-free, safe, and robust completion operations were also accomplished, and the wells that have been put on production show high production rates with low skin.
Full open-hole formation evaluation of the Kvitebjørn reservoir has been carried out with LWD tools. The evaluation has been aided by the development of a novel logging interpretation solution for a LWD density tool, in which the extremely high photoelectric effect of cesium-rich filtrate plays a vital role. Using photoelectric factor and bulk density data, combined with resistivity measurements from both the LWD drill pass and the ream pass, produces a very reliable and consistent net reservoir definition. The final interpretation result matches the core porosity from different lithologies in 3 different wells.
Cesium formate brine has helped Statoil to achieve a remarkable record of zero well control incidents in all 15 HPHT drilling operations and 20 HPHT completion operations in the Kvitebjørn, Kristin, and Huldra fields over a period of 5 years.
A New Drillstring Fatigue Supervision System
Authors: Vincké O. , Averbuch D. , Tollet S. , Lefevre B. , Dupuis D. 
Published: December 2007

Abstract
With the development of complex wells, extended reach wells and deep wells (for deeply buried reservoirs production), drillstring elements are subject to several kinds of cyclic stresses. Eventhough such stresses are often below the material endurance threshold, the induced fatigue accumulation over time may generate the failure of drillpipes while drilling.
Harsh drilling conditions would ideally require an advanced follow-up of the fatigue of each element of the drillstring. Tracking the mechanical and dynamic history of each drillstring element all over its life -from one site to another- is a challenge.
To reach this objective, the team project regrouping experts from IFP, Cybernextix, Vam Drilling and Pride International has developed a new way to monitor the fatigue of each element of the drillstring. The proposed method is based on a RFID (Radio frequency identification) chip (called tag) used in association with a modeling approach to accurately estimate the fatigue damage.
Pertinent parameters are estimated by modeling, based the operational context, and are written afterwards on the referenced element tag associated with each element of the drillstring. Reading of the identification number and the updating of the memory with new information about fatigue duration, etc., are automatically performed while the drillstring element goes through the rotary table upwards.
This new system and its first rig tests are discussed in this paper.
Optimization of Deep Drilling Performance: Benchmark Testing Drives ROP Improvements for Bits and Drilling Fluids
Authors: Judzis Arnis , Bland Ronald G. , Curry David A. , Black Alan D. , Robertson Homer A. , Meiners Matthew J. , Grant Timothy C. 
Published: December 2007

Abstract
A critical cost in future deep oil and gas recovery is the cost to drill a well. This cost is dominated by the rate of penetration (ROP) that becomes increasingly important with increasing depth. Improving the technology of drilling and increasing the ROP will lower the cost to drill a well. This improves the economics of deep exploration and development, potentially increasing drilling activity, increasing production and supply, lowering the cost to the consumer and improving the economy.
Industry partners and the U.S. Department of Energy (DOE) successfully completed benchmark testing of advanced diamond bits and high pressure/high temperature (HP/HT) drilling fluids at high pressures. The paper describes the results of this testing and identifies factors limiting ROP performance at great depth, and the development of drilling fluid systems and bit design philosophy to significantly improve drilling performance. Benchmark results match very well with data from target field applications. This project is part of the DOE Deep Trek program.
Sixteen full-scale tests of 6 inch bits were conducted at wellbore pressures greater than 10,000 psi. Results from high-pressure tests with water and base oil showed very high ROPs are possible before mudding up. When drilling through hard sandstone penetration rates can drop 70 to 80% on switching to a weighted mud. These data emphasize the importance of mud technology in high-pressure applications. Performance of polycrystalline diamond compact (PDC) bits showed in many cases substantial improvements over roller cone insert bits.
Cuttings from Carthage marble and Mancos shale appear to be compressed agglomerates of fine particles and Carthage marble cuttings had low compressive strengths.
The study has concluded that opportunities for improvements in both bit design and smart HP/HT drilling fluids are possible. While rock properties change continuously with pressure the cutting mechanisms at great depths change much more dramatically. Changes in bit design and mud composition, using next generation technology, will be evaluated in Phase II testing.
The significance of improved ROP for deep oil and gas plays include opportunities to reduce well costs and improve the economics of deep exploration and development plays. The net result for operators is cost reduction as well as an improved position on reserves.
Hydraulic Fracturing Down Under
Authors: McGowen J. M. , Gilbert J. V. , Samari E. 
Published: December 2007

Abstract
This paper reviews the fracturing history in the Cooper Basin and summarizes the results of over 650 fracturing treatments characterised by high tectonic stresses, high fracturing pressures, high reservoir temperatures, and stacked reservoir lithologies of sands, shales, and coals. Initial treatments targeted multiple moderately high permeability (1-10 md) formations, while multi-staging operations are now targeting single, less extensive, lower quality reservoirs. The paper discusses the techniques used for predicting and designing for natural fracture leakoff, high near wellbore pressure losses and high fracture gradients. It shows the changes in fracturing ideologies and how they have altered the completion strategies, predicted fracture geometries, fracturing materials, treatment schedules, and post-frac production.
Laboratory Evaluation of an Innovative System for Fracture Stimulation of High-Temperature Carbonate Reservoirs
Authors: Nasr-El-Din H. A. , Al-Zahrani A. , Still J. , Lesko T. , Kelkar S. 
Published: December 2007

AbstractAcid fracturing is the commonly applied stimulation technique in low permeability carbonate reservoirs. Achieving adequate fracture length is challenging due to the fast acid spending rates and high leakoff resulting from these treatments. The problem is exacerbated when treating high temperature formations and compounded with the difficulty of providing adequate corrosion control. In addition, the health, safety and environmental implications of acid handling at surface and shortage of hydrochloric acid in certain regions must also be considered to fully appreciate the challenges imposed by acid fracturing operations. The industry has successfully tried different methods to deal with each, or a combination, of these problems. However, none of them fully address all of the challenges discussed.This paper describes a detailed laboratory evaluation of an innovative, solid-based acid fracturing system to address the above-stated limitations of conventional systems. Extensive laboratory studies, which included acid capacity, etching patterns, conductivity measurements, solubility of reaction products, reaction kinetics, and corrosion tests were conducted at temperatures up to 300°F. The studies demonstrate that the new system results in heterogeneous etching and wormholing in both limestone and dolomite rocks. In addition, this material exhibits increased fluid efficiency as compared to conventional acid fracturing systems, with the potential of achieving heterogeneously etched half-lengths that approach the length-scale achieved with traditional proppant fracturing operations.This paper will demonstrate the applicability of the novel solid-based acid fracturing treatment. Additionally, the paper will highlight some of the unique challenges of placing a solid-based acid system in the formation and the engineering steps taken to mitigate these challenges. Finally, application limitations of the system will be discussed.
Enhanced Fracture Entry Friction Analysis of the Rate Step-Down Test
Authors: Massaras Leon V. , Dragomir Alexanndru , Chiriac Daniel 
Published: December 2007

Abstract
The procedures of the Rate Step-down Test (RST) also referred to as "Step-Down Test" (SDT), and of Conventional Fracture Entry Friction (FEF) Analysis have been used worldwide for over 15 years to separate the Measured Total System Friction (MTSF) into constituent components. The magnitude of the FEF components has served as guidance to design and/or modify the placement procedure and treatment schedule, in order to reduce unplanned terminations (screenouts) of propped hydrofrac treatments.
Conventional FEF Analysis has inherent limitations which produce non-unique (somewhat erroneous) results that can only be overcome with Enhanced FEF Analysis methodology; which bypasses these limitations with innovative methods: appropriately corrected fluid friction factors, non-uniform perforation discharge coefficient, application of Maximum Drag Reduction (MDR) asymptote, and, matching of MTSF with Calculated Total System Friction (CTSF) at all rates of the RST. Several RST examples are analyzed with FEF Analyzer to illustrate and document the success in placing safe and effective propped hydrofrac treatments.
Real-world analogies are used as visual aids to explain the complex processes of FEF, along with RST design methodology, RST execution procedure, and detailed calculation procedures for performing Enhanced FEF Analysis.
Net-pressure history matching is significantly improved, due to the increased accuracy of calculating the magnitudes of the wellbore friction and of the FEF components.