bluuebunny/crossref_metadata_2025_split huggingface dataset:
Underground Combustion Oil-Recovery Experiment In The Venango First Sand, Warren County, Pa.
Authors: Caspero N.A. , Wertman W.T. , Eckard W.E. 
Published: December 2007

Abstract
A thermal oil-recovery experiment was conducted in the Venango First sand, Goodwill Hill oilfield, Warren County, Pa., about 10 miles northeast of Titusville. The Quaker State Oil Refining Corp., Bradford, Pa., performed the experiment with assistance from Sinclair Research, Inc., Tulsa, Okla., and the Federal Bureau of Mines.
The Goodwill Hill field was discovered in 1885. Primary-production operations continued until 1930 when an air-gas injection project, which is still in operation, was started. At the location of the combustion experiment, the reservoir is 400 feet deep and 30 feet thick, with wide permeability and porosity variations. The crude oil is typical Pennsylvania Grade paraffin-base oil with a gravity of 43.9 API and a viscosity of 4.55 cp at 60 F.
The well pattern for the experiment consisted of 5 producing wells, enclosing an area of 1.28 acres, and a central ignition-injection well. An air-natural gas mixture was ignited in the ignition well on July 29, 1961. Ignition was followed by injection of air and natural gas at various rates. The experiment was suspended January 5, 1962, when it became evident that economic oil production could not be achieved.
There was no conclusive evidence that self-sustained combustion was achieved or that combustion increased oil and water production. A slight increase in liquid production was attributed to stripping action caused by the air-injection rates, which were higher than those normally used during air-gas injection.
The Evaluation of Specialized Cements
Authors: Butsch R. J. , Morris C. W. , Wydrinski R. , Kasecky M. J. 
Published: December 2007

Abstract
In recent years specialized cements have been developed for use in the oilfield. These cements have ranged from very lightweight to very heavy cements. They have included additives such as glass or ceramic beads to alter their properties. With an increased use of these cements, concerns have risen about the cement evaluation. Quite often the question is asked, "Can we evaluate these cements?" rather than, "How do we evaluate these cements?" This paper will discuss some logging techniques that can be used to evaluate these new cements.
The desire to cement longer casing intervals without exceeding the formation fracture gradient has led to the use of very light weight cements. These cements have low acoustic impedance values that are not much higher than the acoustic impedance values of drilling fluids. The compressive strength of these cements can also vary significantly. Acoustic impedance and compressive strength are the properties that cement evaluation tools use to differentiate between the fluids and the solids in the casing formation annulus. To identify these differences it is critical that the proper logging techniques and input parameters are selected for the sonic and ultrasonic tools. A statistical analysis of acoustic impedance measurements from the ultrasonic tools has also proven to be valuable for the evaluation of these special cements.
Examples from Alaska, and other areas where these types of cements are being used to solve difficult completion problems, will be shown to demonstrate the use of these cement evaluation techniques.
Practical Applications of NMR Technology Enhance Formation Evaluation, Testing and Completion Decisions
Authors: Davis Bob , McDonald Tom , Aly Mohamed 
Published: December 2007

Abstract
In the last several years the use of borehole nuclear magnetic resonance (NMR) measurements has become more commonplace because the measurements are better understood by the service and operating companies and new applications have been developed. In most wells drilled in Indonesia, basic formation evaluation tools deliver sufficient data for evaluation. However, some wells can be more difficult to evaluate for any number of reasons. NMR measurements provide new petrophysical parameters that can help deal with difficulties such as low-contrast pay resulting from high irreducible water saturation or iron-rich minerals, varying or unknown formation water resistivity, and unknown mineralogy and grain density. Any of these issues can lead to inaccurate evaluations.
Producibility is another issue that standard logs are not designed to address. Determining this property often requires drillstem tests or tests made with wireline formation testers. NMR measurements can give a cost-effective, continuous quantitative indication of rock quality and permeability in lieu of these tests.
This paper will present several case studies from wells in Sumatra and Java where the basic NMR measurements have been used by asset teams to solve difficult evaluation problems. The NMR measurements have been integrated into a full volumetric evaluation of the reservoirs. These examples will cover clastic, carbonate and basement (weathered granite) formations. Production, test results and core analyses have been used to validate the evaluations.
Turn Down the Burner: Impact of Heat Management on the Potter Reservoir, MWSS Field, California
Authors: Fram J. H. , Dailey W. H. , Walker C. J. 
Published: December 2007

Abstract
In November, 2000, prompted by extremely high natural gas prices, steam injection was reduced by 78,000 BSPD (60%) for an extended period in the Potter Reservoir of the MWSS Field located in California. The price environment served to accelerate efforts to reduce injection to the thermodynamic minimum. Production decreased by around 5000 BOPD (SOR ~ 18:1). The Potter formation is a steeply, dipping sandstone reservoir containing 13° API oil and has been under thermal recovery for over 30 years. An extensive surveillance network of observation wells allowed for gathering of high quality heat and reservoir fluid information.
This paper will discuss the theory and approach taken to set lower steam targets. It will also show examples of the impact of lower steam rates on thermally mature properties. Additional unresolved issues concerning our current inability to fully understand the relationship between reservoir (or steam chest) temperatures and oil production rates will also be discussed.
A Simulation Study of Novel Thermal Recovery Methods in the Ugnu Tar Sand Reservoir, North Slope, Alaska
Authors: Sharma Bakul C. , Khataniar Santanu , Patil Shirish L. , Kamath Vidyadhar A. , Dandekar Abhijit Y. 
Published: December 2007

Abstract
The Ugnu reservoir, located in the Kuparuk River Unit on the North Slope of Alaska, is estimated to contain over 6 billion barrels of heavy oil in the form of tar and bitumen. Due to the extreme oil viscosities conventional enhanced oil recovery (EOR) methods are not readily applicable to the Ugnu sands. Additionally, high reservoir heterogeneity creates complications with EOR processes. A detailed simulation study was conducted to evaluate the performance of four novel thermal recovery methods in the Ugnu reservoir. These methods included steam assisted gravity drainage (SAGD) with horizontal injectors, SAGD with vertical injectors, SAGD with electrical preheating (EP-SAGD), and EP-SAGD with vertical injectors. A conventional steamflood was also simulated for comparison as the base case. The effects of various reservoir and process parameters such as well spacing, flood pattern, reservoir heterogeneity, and anisotropy on process performance were studied. The four SAGD based processes were found to be far superior to conventional steamflood, which performed very poorly. An optimum spacing between injector and producer for SAGD methods was determined. The EP-SAGD process was found to be thermally more efficient than SAGD, however, final oil recoveries were comparable for the two methods. Placement of horizontal producer was found to be more critical than placement of the injector.
Improved Means of Reducing Drag in ERD Applications
Authors: Fuller Andrew , Jardaneh Kamal 
Published: December 2007

Abstract
The increasing number of difficult Extended Reach Drilling (ERD) applications in recent years has emphasized the need for reducing drill string drag. Drill string drag can substantially limit weight on bit and negatively effect directional control.
An improved type of drill pipe deployed Non-Rotating Drill Pipe Protector (NRDPP) has been developed that was found, both in laboratory tests and in actual down-hole drilling/sliding applications, to reduce drag inside casing up to 50% of that for bare drill pipe. This new tool incorporates existing NRDPP fluid bearing technology for torque reduction along with a modified geometry and the use of low-friction wear pads to reduce drag.
This paper describes the design and testing of the new "Low-Drag" NRDPP and provides a detailed discussion of three different wells that were drilled using this new tool for the purpose of providing drag, torque, and casing wear reduction. The wells, drilled by major oil companies in different regions of the world, were of varying profiles and possessed a unique set of operational circumstances.
Cheaper Cement Formulation for Lost Circulation Control
Authors: Samsuri A. , Phuong B. T. N. 
Published: December 2007

Abstract
Laboratory experiments had been carried out by using G and special blended cement with various amount and types of standard cement additives, and various amount of local bentonite and sugar cane fiber. The ASTM-C 114 and AAS procedures were used for the chemical analysis and API Spec. 10 procedures under atmospheric and reservoir conditions for the cement performance.
One of the serious cementing problems is a lost circulation, which may occur in high permeability formation, vugs or naturally fractured formation. Therefore this study focused on development of a cement mixture to overcome lost circulation problem and also strong enough to hold casing with minimize damage to potential producing formation. The results shown that optimum size of local bentonite ranging from 150-250μm and sugar cane fiber ranging from 2000-2800μm. A suitable cement system formulation for optimum lost circulation control is 9% local bentonite, 2% calcium chloride, and 0.5 sugar cane fiber with adequate shear bonding strength and formation permeability reduction is about 10%.
Generally, special blended cement has less free water and fluid loss, better strength development but shorter thickening time than G cement. The cost of blended cement is cheap, bentonite is a local material and sugar cane fiber is a waste material, therefore there will be about 48% of the cement material cost saving if this cement formulation is used for an average oil well at 8,000 ft depth. This formulation also proves to be the cheaper choice for cementing job, particularly the shallow well due to the shorter thickening time.
A New Wellbore Position Calculation Method
Authors: Chia C. R. , Phillips W. J. , Aklestad D. L. 
Published: December 2007

Abstract
A method is described for combining multiple wellbore surveys to obtain a single composite, more accurate, well position. Established methods for defining the wellbore position, and its associated uncertainty, rely upon accepting the position obtained from the most accurate survey instrument used in each section of the wellbore. This position is then assigned an uncertainty based on the information from this single survey instrument run. Today, when a modern wellbore is constructed, each section may be surveyed for position many times using one or more magnetic, gyroscopic or inertial survey instruments. By statistically combining the wellbore positions obtained from all of the survey instruments run in a given section of the wellbore a new position, designated the ‘Most Accurate Position’ (MAP), is calculated. The main advantage of the MAP is that its uncertainty is smaller than the uncertainty of any of the constituent surveys. The major benefits of this technique will be to facilitate the drilling of smaller targets at greater distances, allow the drilling of new wellbores in closer proximity to existing wellbores while maintaining accepted safety clearance rules, and improved reservoir delineation.
Technical Developments in Modular Rig Design - Lowering Operator Costs
Authors: Carter Greg J. 
Published: December 2007

Abstract
Modular workover and drilling platform rigs have played an important role in the development of existing oil and gas fields since the 1960’s. The past decade has seen tremendous design improvements in both workover and drilling operations. Improvements range from effective utilization of top drives for sidetracking and extended reach programs to minimizing weight and space distribution of the rig to accommodate minimal space platforms. Case history studies will illustrate how technological developments in modular rig design have increased an Operator’s invested return on their offshore platforms and hired drilling/workover rigs.
The Development of a New Generation of Nitrogen Membrane Unit Will Allow Greater Flexibility and Wider Operational Applications In Offshore Applications
Authors: Pia Giancarlo , Fuller Tom , Allen Tim 
Published: December 2007

Abstract
As underbalanced drilling and intervention operations find offshore applications, development may be restrained by physical dimensions, operational delivery and logistics preventing the wider application of the technology and maintaining the conventional methods with its higher cost base.
The first generations of Nitrogen Membrane units were large stand-alone skids that had no built-in compression and booster capability; these were supplied in separate units. For land-based use in drilling, well intervention and pipeline applications, this presented no problems since space availability was not an issue. However for offshore use where space is at a premium, these additional components presented such a large footprint that their use was difficult in most applications and impossible for smaller jack-up rigs and production platforms, where deck space and loading are major limitations.
In order to facilitate the use of Nitrogen Membrane technology in offshore environments, it was clear that a new generation of units would be needed. Initial development centered on existing land-based units, with primary and booster compression, Membrane and cooling combined in modular two-piece units. This approach provided for a smaller footprint, but lower output per square foot of space occupied and higher individual weights. This output penalty could be made up with additional units but the space occupied was prohibitive. Subsequent development efforts were based on a three-piece unit with prime mover, primary compressor and secondary booster driven in-line through a single drive shaft. A second-generation Nitrogen Membrane unit, with increased output and efficiency, and the cooler skid, were top-mounted on the three-piece unit. A third generation unit is currently in the design and development stage, which will be fully compliant with all offshore regulations for North Sea operations.
This paper will review the existing technology of Nitrogen Membranes. It will detail the development and design of the second and third generation units on which all the major concerns such as performance per weight/area, access, zone and operator compliance requirements and safety were addressed. It will also review all the stages of the developments, the design, manufacture, testing and field problems encountered and the lessons learned from them.
Some wider application of the technology will also be demonstrated due to the improved technology and the cost savings through operational efficiency highlighted.
An Innovation in Designing Underbalanced Drilling Flow Rates: A Gas-Liquid Rate Window (GLRW) Approach
Authors: Guo Boyun , Ghalambor Ali 
Published: December 2007

Abstract
Underbalanced drilling (UBD) has gained strong momentum in recent years because of a number of advantages of the technology including reduced formation damage and minimized lost circulation. Due to the complex nature of water, oil, gas and solid multiphase flow in the UBD systems, numerous runs of sophisticated computer programs are required to draw the boundary of the safe gas -liquid rate envelope. It is highly desirable to have a simple and reliable procedure to perform optimum UBD designs.
This paper describes an innovative procedure to delineate the boundary of the safe gas -liquid rate envelope for UBD flow rates. In developing the safe gas-liquid rate envelope, formation fluid pressure limits the upper bound of the flowing bottom hole pressure and wellbore collapse pressure serves the lower bound of the circulation-break bottom hole pressure. The envelope is closed with boundaries determined by fluid’s cutting carrying capacity and wellbore washout criteria. Detailed procedure for the development of the safe gas-liquid rate envelope using a spreadsheet program is described in the paper. A successful field UBD case is reviewed and compared with the safe gas -liquid rate envelope. This work provides drilling engineers and drilling supervisors an easy-to-use approach to designing and mo difying gas and liquid injection rates in UBD. The safe gas-liquid rate envelope can also be used for evaluating feasibility of UBD under given geological conditions.
Drilling Knowledge Management, What is Missing and Can We Fix it?
Authors: Irrgang Rosemary , Kravis Simon , Nakagawa Edson 
Published: December 2007

Abstract
Although knowledge is predicted to surpass oil and gas reserves as the most important asset in 21st century oil and service companies, engineers remain cynical about the benefits of current knowledge management initiatives. This paper discusses problems such as the strong bias of existing knowledge management systems in favour of document searching and focuses on how overlooked areas can be addressed. Results of a collaborative project with 5 major oil companies aimed at overcoming some important limitations of current knowledge systems are discussed. A key feature of the initiative is software to integrate knowledge capture and reuse into normal work processes. The software uses well data and stored drilling experiences, including problems and solutions, from a global drilling and completions database provided by the member oil companies. Experiences with deployment of this software into oil companies will be covered as well as the results of research projects on automated learning and case based reasoning to enhance the company knowledge base for optimal design of new wells. The study of overall well quality has also been included in the project. By defining well quality metrics and then examining them collectively, we can better assess drilling performance in a given field, and ascertain if the company is using its knowledge to improve new well production and cut costs.
Wet Gas Venturi Metering
Authors: Stewart David G. , Brown Gregor , Hodges David 
Published: December 2007

Abstract
Multiphase metering is becoming increasingly important in the development of marginal oil and gas fields. Many of these fields are only economically viable if they can be tied back to existing platform infrastructure, reducing the capital expenditure required by significant margins. In such cases, several fields are often tied back to common facilities requiring each unprocessed stream to be metered before co-mingling.
Multiphase metering is also a valuable technology in well management, providing on-line information on the production flow; and in well testing, reducing the capital expenditure required to investigate potential new wells.
Wet gas metering is at the high gas fraction end of multiphase metering, typically with a gas volume fraction (GVF) above 90%, and mostly above 95%. Standard multiphase meters cannot operate satisfactorily in such conditions. The development of Wet Gas Meters is therefore a key requirement of the oil and gas industry.
Borehole Stability in Naturally Deformable Fractured Reservoirs - A fully coupled approach
Authors: Zhang Jincai , Roegiers Jean-Claude 
Published: December 2007

Abstract
A dual-porosity fully coupled finite element solution has been developed to model inclined wellbores drilled in naturally deformable fractured media. Four kinds of borehole failure criteria were assumed to describe the reservoir rock behavior. Several application cases were examined for mud weight selections for holes drilled in normal and tectonic stress regimes. Upper and lower bounds as well as most stable borehole orientations were determined. The optimum trajectory of horizontal boreholes was discussed. Furthermore, the stability of a borehole intersecting a weak zone was analyzed.
Deep Water Drilling Performance
Authors: Avignon B. , Simondin A. 
Published: December 2007

Abstract
Since 1967, TOTALFINAELF has been actively involved in deep water drilling operations but the saga really began in 1976 with the building of the PELERIN drill ship which broke a first water depth world record by drilling a well in 925 m of water offshore Algeria. This was followed by another outstanding performance in 1982 when TFE drilled the first well in a water depth greater than 1500 m (1714 m, in the Mediterranean sea). Following these campaigns, there was a lull in deepwater drilling that lasted about ten years.
However, in 1994 the exploration Offshore Angola on the bloc 17 re-activated the group drilling activity in deep waters. Since this time, 62 wells have been drilled in water depth ranging from 500m to 2851 m in Angola, Congo, Gabon, Equatorial Guinea, Nigeria, Brazil and in the GOM. The majority of those wells are challenging exploration or appraisal wells, for which core have been cut in nonconsolidated sands, sand control completion have been run and DST have been performed. Twelve wells are development wells, which have involved installation of subsea completions. All types of rigs have been used from moored semisubmersible, old DP drill ships, to new built semi-submersible and drill ships including two types of dual derrick units.
Those drilling performances leaded to the production start up of the Girassol field by 1400m of water on the 04th of December 2001 with some wells producing over 30,000 BOPD. It will shortly (summer 2002) lead to the start up of the Aconcagua gas field, which is the deepest field ever completed (2200 m of water).
This huge amount of deep water well operations brought a lot of data and experience, the purpose of this paper is to show what type of drilling and completion performance one can expect according to the type of well to be drilled. The paper will compare drilling operations durations achieved for dry hole wells with appraisal wells, including heavy data acquisition program. The type of rig will be analysed with in particular the gain one can expect by using dual derricks drilling rigs. Alternative solutions to conventional Subsea drilling such as surface BOP stack, slender wells will also be discussed.