bluuebunny/crossref_metadata_2025 huggingface dataset:
Case History: A Shallow Gas Blowout Offshore Korea?Another Data Point in Industry's Learning Curve
Authors: Beall J. E. , Horler C. L.
Published: December 2007

This paper reviews a recent shallow gas blowout while drilling with the semisubmersible rig DOO SUNG in 473 feet of water offshore Korea (See Figure 1).The objectives of this analysis are to: Fig 1

FIRST: Substantiate the argument favoring drilling the conductor hole without a riser-if the rig is mobile.

SECOND: Describe procedures which will reduce the risk and cost of controlling the flow if a blowout occurs.
A Task Force Approach to Reducing Stuck Pipe Costs
Authors: Bradley W. B. , Jarman D. , Plott R. S. , Wood R. D. , Schofield T. R. , Auflick R. A. , Cocking D.
Published: December 2007

in 1989 BP formed a world wide task force to focus on lowering its stuck pipe costs. In its campaign to reduce this cost,the task force gathered together key personnel from each of its three operating companies and its research centers. This paper reports on the methods used to produce a substantial reduction in its. stuck pipe costs.
Gratuitous Counsel about Petroleum Markets
Authors: Brown K. C.
Published: December 2007

Economic theory and empirical research yield hints helpful for understanding some of the vagaries of crude and product markets. Examples: 1) If spot prices are much lower than near futures prices, something must be preventing profitable arbitrage. Perhaps storage capacity is filled. 2) Reserves have many characteristics of inventories--they consume time and resources to find and prove. Rational economic agents accumulate inventories only to the extent that their benefits appear to exceed opportunity costs. Current reserves in areas where there is excess capacity, temporary government instability, or production or transportation disruptions may not adequately reflect future production potential. 3) Cartels are hard to administer effectively, especially where the resources, production costs, and goals of the cartel members differ widely. Continue to expect disagreement and "cheating" in OPEC. 4) Empirical estimates of long-run price elasticity of supply and demand are usually too small. Persistent price trends often cause surprisingly large changes in quantity supplied and demanded. Real prices of many minerals and mineral products have historically declined because of substitution and technological change. Be suspicious of forecasts of persistent considerable real price increases in crude and products. 5) Capital will flow to opportunities investors find attractive. Distrust forecasts based on impending "capital shortage." Similarly distrust those who say they need government subsidies, tax breaks, or tariff or import quotas to help them generate capital needed for modernization or expansion.
Another Look at Oil Transportation in and From the Arctic Environment
Authors: Marsden S. S. , Ozarar I.
Published: December 2007

Transportation of crude oil in the Arctic presents unique problems which are not easily handled by the usual hot oil pipelines plus the very large tankers operating in restricted coastal waters. The work described here presents a solution which; would allow completely buried, cold operating pipelines along with tankers carrying an easily dispersible crude oil emulsion which would not form massive oil slicks on coastal waters in the event of an accident.

Sadlerochit crude oil emulsions were prepared in 10% NaCl brines using an especially developed procedure based on an ultrasonic emulsifier. The oil concentration was varied from 10% to 90% (vol.) with the higher concentration ones being HIPR (high-intemal-phase ratio) O/W emulsions. The lower concentrations were Newtonian fluids and the higher concentration ones pseudoplastics. A new kind of variable head rheometer was developed to measure the shear stress—shear rate characteristics at various low as well as ambient temperatures.

The proposed transportation system would require continuous preparation of say 80% oil in 10% NaCl brine O/W emulsions, cooling them to say 20°F and pumping them in completely buried pipelines. Use of the low temperatures would prevent any thawing of the permafrost and for a new pipeline would be considerably less expensive to construct than hot oil line built on supports. At the pipeline terminal, the HIPR emulsion wold be run onto ordinary tankers and transported to refinery markets in temperate climates, where the emulsions would be broken in heater-treaters.

In the event of a tanker accident such as the Exxon Valdez, the O/W emulsion would be fully dispersed in the ocean without formation of a surface slick and it would then be consumed by microorganisms naturally found in the ocean.
The Challenge of West Sak Heavy Oil: Analysis of an Innovative Approach
Authors: Gondouin M. , Fox J. M.
Published: December 2007

The West Sak (Upper Cretaceous) sands, overlaying the Kuparuk field at 2,000-4,500 ft depths, contains heavy oil (12-23 API) at a low GOR. With a range of OOIP estimates of 13 to 25 Billion Barrels, this reservoir, covering 300 sq.miles (777 km2), would rank among the largest known oil fields in the US, but technical difficulties have so far prevented its commercial exploitation. Steam injection is the most successful and the most commonly-used method of heavy oil recovery, but its application to the West Sak presents the following major problems: steam injected from the surface would have to traverse the 2,000 ft (600m)-thick Permafrost layer. Unavoidable heat losses from the steam and production tubings have two detrimental effects:the injected steam quality is greatly reduced, andmelting the Permafrost around the cemented casing could cause the well to sink, with potentially disastrous effects;the reservoir consists of 6 major layers, relatively thin and of medium permeability (ca.150 md);the West Sak formation contains some swelling clays, which, when exposed to steam condensate, further reduce the rock permeability;high well rates, generally required for economic operations in the Arctic, make it imperative to prevent degradation of permeability.

Such difficulties may be overcome by using a novel approach, in which steam is generated downhole in a catalytic Methanator, from Syngas made at the surface from endothermic reactions (Table 1). The Methanator effluent, containing steam and soluble gases resulting from exothermic reactions (Table 1), is cyclically injected into the reservoir by means of a horizontal drainhole while hot produced fluids flow from a second drainhole into a central production tubing. The downhole reactor feed and BFW flow downward in two concentric tubings. The large-diameter casing required to house the downhole reactor assembly is filled above it with Arctic Pack mud, or crude oil, to further reduce heat leaks.

A quantitative analysis of this production scheme for the West Sak required a preliminary engineering of the downhole and surface facilities and a tentative forecast of well production rates. The results, based on published information on the West Sak, have been used to estimate the cost of these facilities, per daily barrel of oil produced. A preliminary economic analysis and conclusions are presented together with an outline of future work. Economic and regulatory conditions which would make this approach viable are discussed.
Large-Scale Loading and Collapse of Natural Sea Ice and Natural-Artificial Ice Laminates
Authors: Lichtenberger G. J.
Published: December 2007

Natural and natural-artificial flood ice laminates up to 85 inches thick were tested for collapse under a variety of loading conditions. The data was empirically correlated using Westergaard's extreme fiber stress formula for elastic plates on an elastic foundation to establish a critical load modulus, which when exceeded resulted in immediate or delayed collapse of the ice sheet. For natural sea ice this critical load modulus is given by Sc = 215 - 2.95 T psi, where T (°C) is the ice center temperature. For laminates with ice center temperatures near −14°C the critical load modulus was found to be Sc = 100 + 1.42 P psi, where P is the percentage thickness of natural ice in the laminate. Seismic data showed only weak evidence of radial crack formation, possibly indicating plastic flow failure at the ice water interface. Circumferential cracks were observed both visually and using seismic methods at locations near those predicted by Nevel's theory for elastic wedges on an elastic foundation. Using this theory, the surface ice tensile strength for both natural and flood ice was found to be 75 psi. Brazil tensile strength tests yielded similar values, with a decrease in the strength for deeper sample locations in the ice.
A Design Method for Testing Procedure for Avoiding Weld Zone Corrosion in Ships and Offshore Structures
Authors: DeGeer D. D. , Zimmerman T. J. E.
Published: December 2007

The degree of corrosion of weldments on offshore structures and vessels depends upon the metallurgical characteristics of steels and welding consumables, the welding procedures, and the environmental severity. A new procedure has been developed for evaluating the preferential corrosion susceptibility of weldments at the heat affected zone (HAZ) and in the weld metal. The procedure uses short term laboratory tests to determine the corrosion susceptibility of the HAZ and weld metal for an "as-welded" specimen. These tests primarily involve the use of the Scanning Reference Electrode Technique (SRET), a highly sensitive technique with good resolution, requiring only a few days to clearly delineate the preferential corrosion susceptibility of a weldment. An empirical design method is also presented which determines, without laboratory testing, the preferential corrosion susceptibility of some weldments with heat inputs ranging from 1.1 to 4.2 kJ/mm. The use of both the SRET apparatus and the design method allows for the selection of materials and welding procedures to obtain maximum resistance to preferential weld zone corrosion.

The accuracy of the SRET apparatus was benchmarked against a collection of long term field tests, using coupon weldments attached to offshore structures and vessels, as well as field corrosion data gathered from actual ship hull weldments. A good correlation was found between the SRET tests and the field data. Also, the design method was derived from the same data base of test data.
Hydrogen Sulfide Forecasting Techniques for the Kuparuk River Field
Authors: Frazer L. C. , Boiling J. D.
Published: December 2007

This is a case study on developing hydrogen sulfide (H2S) forecasting techniques for the Kuparuk River Field. Initial oil production from the field was sweet. However, the field is currently souring while undergoing recovery from a combination of waterflood and water alternating immiscible gas injection. Evidence of microbiological souring and discussion on the evolution of H2S forecasting techniques are provided. The evolution of H2S forecasting techniques involved: 1) developing an initial forecasting model, 2) investigating H2S data on a well and field basis, and 3) altering the initial forecasting model to keep it consistent with H2S data. This work resulted in a model that is consistent with field data. These data indicate that at produced water sulfate concentrations ≥250 ppm, H2S production is independent of sulfate availability and averages approximately seven pounds per thousand barrels of water. Furthermore, these data suggest that H2S that is being reinjected into the reservoir is either being removed (stripped by reservoir fluids and/or scavenged by iron bearing minerals) or reducing H2S generation.
Construction Activities Inside of Air Structures Protected From the Arctic Environment
Authors: Mangus A. R.
Published: December 2007

A very brief overview of the seventy year history of air structures will trace the evolution to encapsulating arctic worksites. Its desirable working under controllable conditions inside an air structure because it results in higher quality of work, year-round work, and improving worker safety.

A encapsulated worksite allows the personnel to use lighter work clothing and move more effectively. Additionally, wind chill effects on people are eliminated plus problem of drifting snow over work and the tools will not occur. The lightness of an air structure allows mobility plus remote site installations by air cargo aircraft.

The manufactured air structure will last for decades like most construction equipment. Air structures can be utilized each winter to construct project after project by an active organization or sold to another firm to recover a majority of the initial cost of the facility.

An Alaskan case history of a three acre (1.21 ha) column free air structure used to shelter construction of one project during the winter of 1985 and another facility during the winter of 1986 will demonstrate these advantages. The author will relate lessons learned and successful use of this facility by two different contractors. Carbon monoxide and carbon dioxide from equipment operating inside the air-structure is the major safety issue. Unique safety concerns and worker protection will be discussed.

Arctic foundation systems for anchoring the air-structures will be presented, plus untested conceptual solutions.

Technology improvements continue to be made and the author will discuss trends in the air-structure industry that will result in more desirable product for use in the arctic.

A list of manufacturers and an extensive bibliography will be provided to assist the practicing professional or researcher.
Kuparuk River Module Crossing Case History: A Critical Arctic Oilfield Transportation Link Is Protected by a Refrigerated Foundation
Authors: Christopherson A. B. , Nottingham D.
Published: December 2007

A case history and design review of the Kuparuk River Module Crossing and its refrigerated foundation are presented. The Kuparuk Crossing incorporated a number of design and construction innovations to meet the challenges of bridging a major Alaskan North Slope river. Among these challenges was the need for a foundation system--to be placed in a continuous permafrost bed--which could support a 2,500-ton (2.26 × 103 Mg) live load on the bridge deck. A temporary mechanical refrigeration system was provided to refreeze subgrade soil disturbed during construction of this foundation. After the removal of the temporary mechanical refrigeration, a passive thermosyphon system was employed as part of the foundation design to maintain the long-term integrity of the frozen soils. A special procedure was used to install and monitor the passive systems in the foundation piles.

The predictions of the thermodynamic design model are compared to five years of post-construction field measurements. General trends of both future performance and foundation stability are discussed and compared to design assumptions. The performance of ground temperature monitoring equipment is also reviewed.
OTH-Backscatter Power Plant Foundation Design for Warm, Ice-Rich Permafrost Soils
Authors: Foster M. L. , Washburn D. S. , Foote D. S.
Published: December 2007

An actively refrigerated, slab on grade foundation was designed for a coal-fired electric generating facility with a total capacity of 11 megawatts. The facility was constructed to supply power to the Over-the-Horizon Backscatter site near Gakona, Alaska. The soil on which the foundation was placed consisted of relatively warm (30°F [−1°C]) permafrost consisting of ice-rich clay averaging 25%-50% total moisture. A 8.5 foot (2.6 m) thick insulated gravel pad was designed for the power plant foundation. A stress analysis for the foundation indicated that a stress of over 2900 psf (139 kPa) would be observed at the permafrost/gravel depth under the power plant boiler. Because of the temperature, properties of the soil matrix, and loading configuration, it was determined that excessive long-term creep settlement could occur. The final foundation design consisted of 55 near-horizontal thermosyphons to remove the heat transferred through the floor of the approximately 80°F (27°C) power plant. In order to add strength to the native permafrost, and thereby minimize the creep settlement, an active refrigeration system incorporating the 55 near-horizontal thermosyphons and over 30 near-vertical thermosyphons was designed to lower the temperature of the permafrost. The excess electricity generated by the power plant made active refrigeration an economically feasible solution to the creep settlement problem. The system was designed to refrigerate the permafrost from the original temperature of approximately 30°F (−1°C) to a temperature of approximately 20°F (−7°C) to a depth of 50 feet (15.2 m) below the existing natural ground level. The lower temperature will significantly increase the strength of the in situ soil, and thus reduce the amount of creep settlement. After the desired temperature is reached, the system will be operated passively to maintain the 20°F (−7°C) temperature. Eight thermistors were installed for weekly monitoring of the subgrade temperature, and weekly settlement monitoring of the foundation was recommended.
Developments in the Application of Fiber Optic Technology to Pipeline Structural Integrity Monitoring
Authors: Griffiths R. W. , Rizkalla M. , Colquhoun I. R.
Published: December 2007

Increasingly, pipelines in unstable terrain are being monitored as a supplement to design stage integrity measures. The quantities monitored most often in this case are strains and displacements. A variety of techniques are being used and considered to assure the monitored quantities are kept within allowable limits.

This paper reviews the potential use of distributed fiber optic sensor technology for direct strain measurement in long, lineal structures such as newly constructed pipeline systems. The components of an opto-electronic system are described. Methods of attaching the fiber optic sensors to pipelines are reviewed. Data from large scale laboratory pipeline-deflection tests are presented.

Utilizing the inherent low loss of optical fibres and "optical radar" techniques, the passive distributed optical system described in this paper is shown to hold promise for high cost effectiveness in practical applications.
Dynamics of Subsurface and Geocryological Conditions in Foundations for Power Structures in the Northeast Region, USSR
Authors: Krivonogova N. F. , Kagan A.
Published: December 2007

Subsurface and geocryological conditions impacting the construction of power structures in northeast USSR are reviewed. The sites are characterized by nonhomogeneous geological structure, cryogenic texture in the foundation rock or soil, and sharp differences in temperature conditions of the rock or soil within the foundation area. Large temperature variation is exhibited by the presence of talik zones composed of highly permeable rock confined by ice-saturated, ice-rich ground. A. significant loss of the bearing capacity and an increase in permeability of rock or soil that would endanger the stability of the structures were predicted upon thawing. However, geocryological factors were of paramount importance in adopting design solutions.

Examples of design solutions and modifications during construction included: (l) the foundation rock or soil was kept frozen; (2) talik zones, both natural or those formed during the construction, were frozen; (3) impervious elements of the storage dams were installed using refri gerating units of different types.
Effective Unconsolidated Core Preservation in the Arctic Environment: An Aid to Accurate Reservoir Evaluation
Authors: MacGregor K. W. , Park E. I. , Sincock K. J. , Piekenbrock E. J.
Published: December 2007

Accurate data from undamaged core is key to evaluating the substantial reserves of moderate to highly viscous oil held in Arctic unconsolidated formations.

This paper describes a laboratory technique which can be used to design trip schedules to reduce gas-in-viscous-oil expansion core damage. This technique, based on X-ray CT core structure visualisation, indicates the majority of core dilation due to retrieval occurs during the last 500 psi (3.45 MPa) of decompression. Reducing the trip rate over the latter stages of the trip will therefore result in better quality core.

Improved fibretube core processing systems compact enough for Arctic enclosed rigs; and methods of preserving core structure through the rigours of Arctic transportation are also described in this paper.
Peculiarities of Rock Massif Behavior in a Zone of Transition From Subzero to Above Zero Temperatures
Authors: Chislov A. I.
Published: December 2007

This paper reveals the results of the studies relating to a rock massif behaviour in a zone of transition from subzero to above - zero temperatures. Distribution of rock areas having above - and sub - zero temperatures and various aggregate moisture condition had been established within one horizon. For the first time underpermafrost waters had been found in the areas with tectonic disturbances and high rock jointing. While opening water - bearing areas a water inflow totalled 3-8 m3ph (up to 25m3ph), and in 4-5 months of flowing by itself it lowered to 0.6 - 1 m3 ph. Maximum rock temperature ( +0.6 °C ) was fixed during opening driving with its temperature further lowering by total the negative temperature balance of the air fed to a mine. Rock strength characteristics considerably changed for the worse comparing to the upper horizons. At was established that by rizing the temperatures from −2.2 °C to above - zero ones rock strength lowered by 18 - 20%, and by water - soaking compressive rock strength decreased by 9-55%, tensile strength by 7 - 40%, cohesion by 19 - 49%, an angle of internal friction by 6-15%, Poisson's ratio by 18-25%. The rocks of a transition temperature zone tend to freezing and partially to packing, the compressive strength of frozen together samples reaching 0.6 MPa. As a result of a pressure waters inpact washing - out of binding material from cracks takes place, what lowers the stability of mine workings.

Frequent roof and wall caving at a horizon of transition temperatures made it necessary to provide a metal arch support with tight wall and roof lagging (with a support lagging behind the face not more than 2.5 m) for mine workings.

The instability of mining workings made it necessary to change from one method of rock pressure control (pillars) to another (caving).

The conducted investigations allow to predict the behaviour of rock massif of metamorphic rocks when reaching a zone of transition from subzero to above - zero rock temperatures.
Drilling and Sampling of Permafrost for Site Investigation Purposes: A Review
Authors: Riddle C. H. , Hardcastle P. K.
Published: December 2007

The methods used for drilling and sampling of permafrost for site investigation purposes have evolved significantly during recent years. These changes are due in part to the development of new technology and equipment. A review of the applicability of current drilling and sampling methods in various frozen subsurface materials is presented.
Effects of Total Water Content on Dynamic Properties of Frozen Soils
Authors: Fukuda M. , Huang S. L.
Published: December 2007

A series of laboratory tests on frozen soils were conducted to investigate the variability of ultrasonic velocities passing through frozen soils in relation to changes of sample temperatures. Frozen soil samples were placed in a kerosene bath, between the transmitter and receiver of an ultrasonic device which was operated in a frequency range of 0.5 to 2.0 MHz with the dominant frequency at 1.0 MHz. The velocity of an ultrasonic wave was determined based on the differences in delay time of the first-arrival waves passing through the samples and kerosene.

Statistical analysis revealed strong correlations between the measured velocity and temperature as well as total and volumetric unfrozen water contents. The ultrasonic velocity was found to be highly temperature dependent in a range of 0°C to -10°C. At a temperature near the thawing point of ice the velocity was considerably lower than the velocity measured at a lower temperature due to an increase in unfrozen water content. A general power model was presented in this paper to describe these relationships. Three ranges of velocities were categorized in accordance with the types of soils, namely, sand, silt, and clay. Among the soils tested, sandy soil had the highest velocity at -1°C and the clayey soil had the lowest. The clayey soil was, however, more subject to temperature variation and the silty and sandy soils were less responsive. Total water content was noted to have influence on the velocity of soils as well. In general, a soil with a higher total water content has a larger velocity at -1°C, and is, however, less variable over the temperature range tested.
Slope Stability Problems in Open Pit Coal Mines in Permafrost Regions
Authors: Vakili J.
Published: December 2007

The instability of highwall slopes, exposed to thawing, in open-pit coal mines in permafrost regions is described. Remedial measures are proposed to prevent shallow as well as deep slope failures in these regions. It is shown that by introducing a wide bench in the highwall at the bottom of the permafrost layer and by proper designing of interbench slope angles, and equipment distance from slope crest, such failure can be avoided or minimized.
Vertical Support Member Design in Areas of Ponded Water Over Permafrost
Authors: Wineland John , Yarmak Edward , Ganguly Partha
Published: December 2007

Elevated pipelines are the norm in the North Slope oilfields. Problems were observed with tilting, settling, or frost-jacking of Vertical Support Members (VSMs) supporting portions of the abovegrade piping. Further observation showed that the majority of the problems existed where the VSMs were installed in, or adjacent to, the numerous shallow ponds or lakes that dot the tundra. Ponded water causes a condition where the local permafrost is warmer than the surrounding permafrost because much of the winter's cooling is absorbed by the phase change from water to ice and then lost during the summer due to the high solar absorbance of the water surface. To further understand the magnitude of the warming condition, a drilling program was undertaken to determine subsurface soils and groundwater conditions and temperatures. From this data, a correlation was developed between the ponded water depth and the subsurface temperature profile. Subsequently, a procedure was developed to design adfreeze (standard) VSMs, Helix VSMs, and Thermo Helix VSMs in areas of ponded fresh water. This paper presents the temperature profile of the permafrost beneath ponded water and addresses the development of design procedures for these conditions.
The Instantaneous Strain of Frozen Sand
Authors: Soo S. , Adams L. T.
Published: December 2007

In engineering application, creep strain of frozen soil was modelled by a pseudoinstantaneous strain and a secondary creep law. The pseudo-instantaneous strain was often neglected by researchers because it is usually less than 10% of the total strain in a long term situation. Nevertheless, many cases of frozen soil structural analysis require computation of pseudo-instantaneous strain. There are two ways to determine the pseudo-instantaneous strain: (1) after separating the pseudo-instantaneous strain into an elastic strain and a plastic strain, compute the elastic strain by dividing the stress by an elastic modulus, and compute the plastic strain with a power law; (2) use a simplified approach to obtain the pseudoinstantaneous strain by dividing the stress by a secant modulus.

This project investigated the pseudoinstantaneous strain of frozen sand through a serious of uniaxial compressive tests including both constant stress (creep) and constant strain rate tests. These experiments were conducted in two large size freezers. A front-end loading machine with dead weight was used to conduct creep tests. An uniaxial compression machine with constant displacement rate control was used to conduct constant strain rate tests. Two sample sizes, 2.94 in. (74.7 mm) diameter by 7.25 in. (184.2 mm) in length and 1.45 in. (36.8 mm) in diameter by 4.375 in. (111.1 mm) in length were used. Ottawa sand passing #30 sieve and retained on #140 sieve was used. The coefficient of uniformity was approximately 1.5. Distilled water was used to mix the. samples. Sand concentration were 64 and 70 percents by volume. The sand volume fraction was determined by preweighing the amount of sand and water. Samples were frozen to desired temperature before testing. A temperature probe was embedded at the top portion of each specimen to monitor its temperature during testing. A thin membrane was used to protect the specimen from evaporating. Specimen temperature were from −5 to −11 degree C. Temperature variation during each test was within 0.5 degree C.

In creep test, specimens were loaded until the straight line portion of creep curves (secondary creep) was reached.; Then, the straight line portion of the curve was projected back to vertical axis at time zero to obtain the pseudoinstantaneous strain. The secant modulus was obtained by dividing the applied stress by the pseudo-instantaneous strain. The relation between the secant 'modulus and temperature is shown in figure 1. The secant moduli were found not sensitive to sand concentration. In constant strain rate tests, a deformation rate 0.113 inches per minute was used. Elastic-modulus was obtained from the initial slope of the stress-strain curve. The elastic modulus was shown in Table 1. The secant modulus was about 1 to 3 percent of the elastic modulus. The plastic strain was set equal to the pseudo-elastic strain since the elastic strain is negletable. Relation between the applied stress, the plastic strain, and temperature is shown in figure 2.
Acid Stimulation of Endicott Kekiktuk Formation, North Slope, Alaska
Authors: Hsi C-K. D. , Strassner J. E. , Blosser W. R.
Published: December 2007

A combined laboratory and field study was conducted to evaluate the susceptibility of Endicott Kekiktuk formation to acid stimulation treatments and to optimize treatment performance.

Endicott crude oil causes severe sludging and emulsion problems when mixed with concentrated acids. Iron concentration aggravates emulsion and sludging problems, especially ferric ion. However, the associated permeability damage can be effectively reduced with the addition of proper antisludge/demulsification chemicals in acids and by reduction in acid strength and complexation or reduction of ferric ion. Laboratory geological analyses, acid solubility tests, and acid core flow tests further indicated that half strength mud acid gives similar stimulation performance than full strength mud acid with less weakening of rock strength and fewer fines migration problems following acid treatments.

Actual field acidizing treatments conducted at Endicott Field using 80 gal/ft half strength mud acid with proper additives have shown good productivity increases with better balanced production profiles. No evidence of fines migration has been observed in the post treatment production well testing.

Selection of the acid treatment compatible with reservoir fluids and lithology will minimize formation damage and lead to increases in production.
An Evolving Description of a Fractured Carbonate Reservoir: The Lisburne Field, Prudhoe Bay, Alaska
Authors: Missman R. A. , Jameson J.
Published: December 2007

This paper traces the evolution in models of the Lisburne carbonate reservoir from early wildcat days, through the decision to fund primary development, to waterflood assessment. This work is an integration of geologic and reservoir studies based on nearly ten years of extensive data collection (well test, core, log, pressure and field performance data). Early reservoir descriptions assumed uniform enhancement of continuous pay layers resulting from small-scale fractures. Additional recovery over solution gas drive was expected by gravity drainage and waterflood. Integration of performance and geological data after field start-up reveal greater heterogeneity than originally thought: faults and irregularly distributed fractures dominate performance; much of the porosity is ineffective; and the producing oil-water contact (OWC) varies by as much as 300 ft [90 m]. The evolution in simulation techniques reflects the evolution in geologic models toward increased recognition of heterogeneities.

The complexity of the Lisburne reservoir is a result of faulting, two periods of uplift and erosion, and three distinct phases of porosity development. Particularly important among these diagenetic events is the youngest phase of porosity development, which post-dates significant faulting. As a result, many faults are open and conductive. An additional complexity is a high permeability layer created by a laterally extensive set of small open fractures beneath an unconformity at the top of the reservoir.

Initial development was based on models with limited data which understated the impact of these heterogeneities. In retrospect, several important clues and their implications were not fully appreciated. Despite extensive data collection, the unpredictable influence of fractures still creates uncertainties in reservoir description (e.g. well performance cannot be accurately predicted pre-drill).

Recommendations for evaluating potentially complex carbonates include: give full weight to known uncertainties, conduct inter-well tests early in the evaluation, and minimize risk by proceeding gradually with field development.
Gas Measurement with Large Venturi Tubes at Prudhoe Bay, Alaska
Authors: Metz W. P. , Bruchie J. D. , Fritz R. H.
Published: December 2007

Ten large diameter (24 and 30 inch) venturi tubes have been calibrated at flow rates of 40 - 220 MMscfd (10-12 million Reynolds Numbers (NRe)) and have exhibited meter flow coefficients exceeding 1.0. A check calibration was made with one of the 24-inch meters at another calibration lab at expected operating conditions of 500-900 MMscfd (30-60 million Reynolds Numbers (NRe)). This meter calibration also exhibited a meter flow coefficient exceeding 1.0 and varied from the extrapolated initial calibration data by almost 2% in the expected operating range. This check meter flow coefficient, when plotted against NRe, exhibited a non-classical shape.
Adverse Telluric Effects on Northern Pipelines
Authors: Seager W. H.
Published: December 2007

New information regarding the effects of tellurics has been discovered by the use of special equipment to measure the true polarized pipe-to-soil potential even in the midst of a severe geomagnetic disturbance. [The Aurora Borealis (northern lights) is a manifestation of this occurrence.] Heretofore such information was not available and indeed the effect of the often observed tellurics was strictly a matter of conjecture and speculation.

We have now discovered that tellurics can and do pose a serious threat to coated pipelines in the auroral zone, extending from Northern Montana to Great Bear Lake, and of course elsewhere at similar (geomagnetic) latitudes.

The paper discusses tellurics, their origin, magnitude and frequency of occurrence, the equipment utilized to determine their effect on cathodic protection levels and more importantly, their ability to depolarize apparently well protected pipelines.

Means for successfully controlling the adverse telluric effect are also discussed.
Gas-Producing Units Construction Experience in the Arctic Regions
Authors: Zavizion V. G.
Published: December 2007

The engineering conception of gas, condensed gas and oil exploration, development and production in the Artic and Subartic areas rests on large scale projects of energy industry for the society, results in the specific economical activities in these regions, taking into consideration the climate and sensetive environment, poor infrastructure and the high level of ecological risk.The development of the united gas supply systems differs much from the analogous programs in USA, Alaska and Canada. Having difficult geological features and hydrometeorological conditions, we note a high rate development of the gas fields. On account of that the updated industrial methods were elaborated, studied and examined. The methods were developad prior to the site construction. The methods include the ingeneering of pile foundation, -the use of local materials (excluding ore and mineral deposites),-the transportation of the super-blocks by waterways leading by ice -breakers,-the technological equipment designed as big block structu res,-the expeditinary character of work and permanent personal shift, and finally the incorporation of the environmental impacts in the main construction projects.

This paper describes progressive organization of the pipeline construction activities in the Far North areas, such as Yamburg region gasfields of the Northern part of the West-Sibirian Plain on the Tazovsk peninsula.
Environmental Research Project for Yamburg Gas Fields
Authors: Chlenov A. V.
Published: December 2007

Intensive development of gas and oil fields in the Arctic Regions provokes ecological disbalance and results in the new nature-technical formation: "nature-ecosystem", which in its turn calls for the revision of the complex program of research and practical measures for invironmental protection. The main objective of the system is to bring down the technogenic impact that goes together with the development of the fields and to restore the ecological balance in the newly developed system.
Database and Network Technologies: An Integral Tool for Methane Development
Authors: Bain L. R. , O'Leary J. M.
Published: December 2007

Taurus Exploration, Inc., an oil and gas exploration and production division of Energen Corporation, has made a large investment in computer technology as an integral part of its research and development. Computer applications have evolved in a continuing effort to refine and customize available technology. Taurus has developed database applications that are industry specific and that match the business functions of the company. These are relational databases, that is, information that is updated in one file is automatically updated in all other relevant files through the use of file indexing. By employing the use of local and wide area networking, Taurus has developed an automation capability that allows its Methane Department to more effectively track development, production, and associated cost information. Relying on its networking and database capabilities, Taurus can make quick and accurate decisions concerning project development, as well as daily field operations.

Taurus has installed local area networks at its corporate headquarters as well as each of its four remote field offices. These local area networks have been integrated into one comprehensive communication tool. Each field office sends current well construction and production tracking data to the main network at Headquarters. Using remote Ethernet bridges and DSU/CSU's (Digital Service Unit/Channel Service Unit) attached to dedicated 56 Kilobits/Sec DDS telephone lines, the four remote network sites have been connected into a single integrated network system. This configuration allows Taurus to maximize employee time and productivity by sending and receiving current well and cost information, electronic mail, and documents.

The basic building block for Taurus' database applications is the Advanced Revelation™ (AREV)* programming language. Such intuitive applications are the product of strong design, logical organization, consistent presentation, and the heavy reliance on user input. The system developers need abundant software tools to achieve a flexible environment for prototyping specific functions of the system. Automated filing systems, applications generators, query languages, and programming languages are all key ingredients, but they alone are not the only key to the success of Taurus' database applications.
POVLIFT: A Computer Program for Designing and Optimizing Intermittent Gas Lift
Authors: Solesa M. , Cveticanin S. , Gligoric G.
Published: December 2007

A mathematical model of hydrodynamic processes i intermittent gaslift is described. The many facets of fluid flow accrue from continuous changes of the hydrodynamic and thermodynamic conditions, the mathematical solution of unsteady fluid flow was simplified by introduction of certain assumptions and boundary conditions. These synthetic, analytical solutions were used to develop the "POVLIFT" program for designing and optimizing intermittent gaslift.
Permeability from Logs: A Hypermedia Microcomputer Tutorial
Authors: Nagel W. A.
Published: December 2007

Permeability from Logs utilizes a relatively new type of interactive computer instruction that falls in the category of hypermedia. This tutorial includes hypertext, voice, music, graphics, animation, and interactive computation. The idea is to allow the user to select only that detailed information he or she needs — plus incorporate an element of entertainment while learning. The program can be run on the Macintosh using Apple Computer's HyperCard, or on IBM-compatibles using Spinnaker Software's PLUS operating under Microsoft's Windows 3.0. For the Macintosh version, HyperCard's object-oriented programming language HyperTalk was employed. The PLUS programming language PPL was used for the DOS version.
Building User-Friendly Interfaces for Petroleum Software: The Contribution of X-Window System Based Tools
Authors: Desaunay M-L. M. , Jourdain M. A. , Viretto M. , Le Louarn C.
Published: December 2007

Petroleum softwares process numerous data and need many color graphics in order to visualize and to compare results. To answer this needs L'Institut Français du Pétrole (IFP) has selected the window manager Motif© based on the X Window System©. We present a model which has been realized with Motif for a reservoir simulation program. In this paper, we discuss how to choose an interface builder above Motif to simplify the programming.
Intelligent Systems Application: Field Drilling Procedures
Authors: Kendall H. A.
Published: December 2007

Expert system technology links an expert's domain expertise on a narrow topic to a rule structured pattern. The user addresses the knowledge-base to obtain advice on his problem.

An intelligent system utilizes the logical power of an expert system, and combines this with hyper-media, databases, external programs, graphics, and report generation to produce an intelligent application. This powerful application permits the user to perform any task within the system.

The Houston Drilling Group undertook the task of preparing the Amoco Canada Drilling Manual as an intelligent application. The manual is totally interactive and allows the user to instantly access any topic in the manual.

All equations needed for drilling performance are interactive and linked to the appropriate reference material. Reports needed are filled out and may be stored as files or printed. Reports can be called back and modified. Field procedures may be viewed or printed and used as disposable hard copy. Graphics may be viewed or printed. The system also includes some minor advisory systems.

Amoco chose a rule based expert system with hypertext capability. The run-time version is IBM compatible and runs on 286 or 386 machines with a VGA monitor.

It is extremely user-friendly. The application requires 4.2 megs, most of which is the extensive graphics needed. The prototype application has expanded to where it now controls over 35 megs of data, graphics files, and advisories located in over 1000 files, and includes the ability to launch conventional technical computing programs. Limits are determined only by the available host hardware.
A Machine Learning Approach to Studies of Recovery Efficiency
Authors: Brown J. P.
Published: December 2007

The American Petroleum Institute published studies o† Recovery Efficiency in 1967 and 1984, The first report provided useful correlations froα an industry database, but the second showed that, without subjective weighting, the 1967 results appeared invalid. This new independent report demonstrates that, through Machine Learning, objective predictions can now be achieved.
Application of Preprocessing Software in the Initialization of Kuparuk Full-Field Model
Authors: Choo Y. K. , Wethington W. B. , Lederer M. C.
Published: December 2007

This paper describes the use of a graphical pre-processing software to generate the grid block array input data for the large scale Kuparuk Full Field Model. Geological and reservoir property maps generated with various mapping packages were imported along with the 77 by 88 simulation grid. Computing time for calculating the entire grid block array data was approximately 45 minutes on a VAXStation 3200.

The pre-processor greatly expedited the task of initializing and updating the model. An estimated two man-months of engineering time were saved. The compatibility of the preprocessor with the simulator helped to ensure data consistency. Juxtaposition of sands due to faulting and truncation were handled automatically using non-standard grid block connections. An inactive middle layer was extracted while preserving the proper depths of the lower sands, resulting in significant savings in CRAY run times and memory requirements.
A Detecting Technique for Production Rate Decline-Curve Analysis with Residual Plots
Authors: Chen Zhigang
Published: December 2007

This paper describes the use of residual analysis in production rate decline curve fittings and performance predictions. Residual analysis, in statistical term, is an easy and quick check of any assumptions being violated under certain hypothesis test, meaning an attempt to discern regression drambacks or pitfalls if any. In production rate decline analysis, residual analysis technique is used to demonstrate (1) the validity of decline equations or models for given rate-time data, and (2) the reliability of the estimated parameters, such as qi, n, Di, and then that of future performance predictions. The emphasis of the study is on the detecting analysis of Arps' decline equations, with other forms of empirical expressions included. For the hyperbolic equation which is slightly more difficult to solve, eight typical numerical solutions are analyzed. These solutions do not often reach good agreement with each other for field data. Graphical residual analysis shows which solution fits the decline trend best, and which thereafter gives reliable performance and reserve predictions. A microcomputer-aided commercial software is developed and has found applications in China's oilfields.
An Advanced Kick Simulator Operating in a User-Friendly X-Window System Environment
Authors: Vefring E. H. , Rommetveit R. , Børge E.
Published: December 2007

A kick simulator has been developed for use on a work station with Unix operating system and X Window System installed. Advanced mathematical models are used to calculate the development of gas kicks and oil kicks in water based and oil based drilling muds. In the preprocessor the user sets up the input data in an environment with help functions and default values. When the simulator is running, the user can observe a number of selected surface and downhole kick parameters vs. time and space plotted graphically on the screen. In the postprocessor the user can display different physical parameters vs. time and space on the screen and make hard copies of them.
Computerized Directional Well Planning for a Dual-Target Objective
Authors: Maidla E. E. , Cordovil A. G. , Pereira J. J. , Falcão J. L.
Published: December 2007

A method is presented to plan a directional well through two targets, considering bit-walk, and determine the surface location that meets a given set of constraints.