bluuebunny/crossref_metadata_2025_split huggingface dataset:
Where and How Not to Run PDC Bits
Authors: Keller W. S. , Crow M. L. 
Published: December 2007

Abstract
A comparison has been made of the results obtained with a new soft formation PDC bit (the Security STRAT-X Bit) and those obtained in a wide range of formations with the various types of PDC bits currently available. The results indicate that, at present, PDC bits are special products for special situations. The clearly superior results have been obtained in homogeneous soft formations when the bit hydraulics and application practices have been appropriate for the particular bit design involved. Very high penetration rates and significant reductions in cost/foot have been achieved when bit design, hydraulics, mud and application practices have been matched well with the bit characteristics. However, even the newest and most productive PDC bits cannot compete when the formation is unsuitable for the particular bit design in combination with the drilling fluid and the hydraulics available. A review of several specific examples in South Texas, the North Sea, and the Rocky Mountains illustrate what can be done with currently available PDC bits, and how to identify those circumstances under which PDC bits should not be run. The results also indicate how to identify when a formation change requires that a PDC bit be pulled or when one can drill through hard streaks and retain the high productivity of the PDC bit for the softer portions of the formation. Maintaining a full gage hole under these conditions is shown to depend critically on bit design and control of weight and rpm.
Analysis of the Invert Emulsion Oil Mud-Polycrystalline Diamond Bit System in Shallow Permeable Formations
Authors: Golis S. W. 
Published: December 2007

Abstract
Recent field experience with shallow, normal pressured wells in South Texas demonstrated an invert emulsion oil mud employed with a polycrystalline diamond compact (PDC) bit significantly increased PDC bit rate of penetration (ROP) and life. Each well used an invert emulsion oil mud from surface casing to total depth and a PDC bit to drill the majority of the same interval. This resulted in substantial cost savings compared to KCl/polymer and freshwater mud systems.
To realize the full cost savings potential, hydraulics and mud programs were designed to maximize PDC bit performance and minimize oil mud costs. This paper examines field results and develops a correlation between hydraulics and mud programs and optimum invert emulsion oil mud-PDC bit performance.
Potential Petroleum Source Rock Deposition in the Middle Cretaceous Wasia Formation, Rub'Al Khali, Saudi Arabia
Authors: Newell K. D. , Hennington R. D. 
Published: December 2007

ABSTRACT
Stratigraphic correlation and regional geochemical sampling in the Rub'Al Khali (The Empty Quarter) of Saudi Arabia indicate at least two potential petroleum source rock units occur in the middle Cretaceous Wasia Formation. These two sequences, informally named the Safaniya "source rock" and the lower Mishrif, are dominated by oil-prone amorphous (Type II) organic matter, in places in excess of 10 weight percent organic carbon.
Both units are fine-grained pelagic lime mudstones which were probably deposited in relatively quiet anoxic waters of large intraplatform embayments or basins. The Safaniya "source rock" and the lower Mishrif reflect strong marine transgressions on the Arabian craton in Albian to Cenomanian and Cenomanian to Turonian time, respectively. Regressive-phase sedimentary rocks overlying these two transgressive organic-rock phases are generally poor in organic carbon despite being deposited, in part, in similar forereef open-marine depositional settings. The sea-level high-stands associated with the Safaniya "source rock" and the lower Mishrif are partly synchronous with two recently described "oceanic anoxic events" respectively occurring in late Barremian to late Albian time and late Cenomanian to early Turonian time. Although there is a credible time correlation of these organic-rock units with oceanic anoxic events, their connection to oceanic anoxic events could be strengthened if they could be traced out to the vicinity of the middle Cretaceous continental margin. Unfortunately, lack of information from adjacent areas prohibits determining the complete extent of the organic-rock units. The organic richness of these sediments could therefore also be the result of euxinic conditions locally developed within silled basins of the Tethys epicontinental sea.
Unique Ultra Light-Weight Cernent Slurry Compositions for Use in Unique Well Conditions, Laboratory Evaluation, and Field Performance
Authors: Tanner C. H. , Harms W. M. 
Published: December 2007

ABSTRACT
In many areas of the Middle East severe lost circulation problems encountered while drilling and cementing are commonplace. However, due to recent technological developments in ultra light weight cement compositions the feasibility of obtaining mud and cement returns in these situations has been greatly improved.
Evaluation of Stimulation Treatments in Appalachian Tight Gas Sands
Authors: Charles J. G. , Hudock K. D. , Udick T. H. , Hall D. R. 
Published: December 2007

ABSTRACT
Hydraulic fracturing is the most common method used to improve production from wells drilled into "tight" formations. Accurate fracture design is essential in order to obtain highly conductive and deeply penetrating fractures. In the past, many stimulation treatments in the northeastern United States had little basis for design. Thousands of wells have been fractured and comparative analysis of different techniques was extremely difficult. This paper attempts to evaluate fracture design in relation to tight gas sands in the northeast.
A review of the major variables affecting hydraulic fracture design is included and a discussion of three pressure transient methods used in the evaluation is presented. Pressure buildup analysis was used to determine effective reservoir permeability and pressure. Type curve matching was used to approximate fracture lengths and to predict production resulting from changes in fracture geometry. Computer reservoir simulation analysis helped in more accurately modeling the reservoir to support the production forecasting.
A case history detailing this method of evaluation in the Medina Formation is discussed. Actual field data are compared to the predicted results.
A field study is also presented which deals with the "Clinton" formations in Ohio. A number of wells were evaluated (after stimulation) with type curves and some ideas on job designs are suggested.
Decline Curve Analysis in Fractured Low Permeability Gas Wells in the Piceance Basin
Authors: Stright D. H. , Gordon J. I. 
Published: December 2007

ABSTRACT
Production decline curves of three representative low permeability gas wells in the Piceance Basin are analyzed. These wells produce from theMancos "B", Mesaverde and Wasatch formations, respectively.
It was found that long term production in these wells could be approximated using linear flow equations. This observation leads to the development of a decline curve method for predicting rate-time behavior based only on one or two years of production data. The method is easy to applyand requires only data which is routinely reported to state oil and gas regulatory agencies. This type of data is public information and is readily available in most states.
The observed long-term linear flow behavior indicates that fracture lengths are much longer than would beexpected from hydraulic fracturing treatments. Possible explanations forthis behavior are discussed. The possibility of using short-term test data to define the long-term production decline curve is also discussed.
Three-Dimension Reservoir Simulation, Sadlerochit Formation, Prudhoe Bay Field
Authors: Thayer P. T. , Puente P. G. 
Published: December 2007

ABSTRACT
A three-dimensional, three-phase reservoir simulator has been used to "model" the reservoir behavior of the Sadlerochit Formation, Prudhoe Bay Field, Alaska. The main objectives of the study are: To examine the effect of various proposed operating conditions on gas reserves and deliverability.To conduct sensitivity studies to determine optimum operating strategies from the gas purchaser's point of view.To monitor field performance in order to identify possible areas of concern to the gas purchaser.
A primary goal of the study was to develop a fairly small and simple model, easy to update, which could be used to run a large number of different cases at a reasonable level of computer cost.
To date, a very good history match has been obtained. That match has been updated three times with additional production and completion data and several prediction runs have been made.
This paper will describe the methods used to develop certain input parameters for the model, the process of calibrating the model with past production (history match), and the results of prediction runs.
A Field Proven System for Selective, Multizone, One-Trip Gravel Packing
Authors: Jefferis R. G. , Bruist E. H. , Botts T. M. 
Published: December 2007

ABSTRACT
Newly developed inside casing gravel packing tools have been combined with slurry packing techniques and gravel pack logging to provide a highly successful, field tested, gravel pack system. The system allows multiple, isolated zones to be selectively gravel packed with only one trip in the hole. The one-trip feature of the system not only allows long, multiple zone wells to be completed quickly, but it also reduces and simplifies the number of operations resulting in a more dependable and relatively trouble-free completion method.
The paper describes the design and operation of the gravel pack tools and liner assembly, the fluids used in the gravel packing, and the application and interpretation of the gravel pack log. A summary of the experience gained with the system to date is also given.
The Application of In-Situ Steam Foams To Improve Recovery in Mature Steam Drives
Authors: Eson R. L. , O'Nesky S. K. 
Published: December 2007

ABSTRACT
Gravity segregation (steam override) and poor areal and vertical sweep efficiencies have limited recoveries in many heavy oil reservoirs since the first thermal projects were initiated in the 1960's. In many instances the injected steam prematurely breaks through into producing wells creating steam channels. In-situ steam foams have proven effective at reducing the mobility in these steam channels and diverting the injected steam into alternate flow paths, thus improving the sweep efficiency of the steam drive process.
This paper describes the efforts associated with the performance under two Department of Energy (DOE) cost-sharing contracts to reduce steam channeling in a conventional steam drive using in-situ steam foam additives. Three steam injection patterns, each being treated with a different steam foam additive, will be presented. In each of the cases, the steam foam additive altered the sweep efficiency and incremental oil production was noted. The cost to produce an incremental bbl of oil varied from $1.50 to $48.81.
Viscous Fingers and Gravity Tongues in CO2-Steam Stimulation
Authors: Claridge E. L. , Dietrich J. K. 
Published: December 2007

ABSTRACT
The presence of highly viscous bitumen and absence of an initially mobile water phase in the Cold Lake (Alberta, Canada) Upper McMurray formation reduced the tendency for CO2 viscous fingering (unstable frontal advance) to occur in simulations of the cyclic CO2/steam process. Highly-cemented sandstone lenses within the bitumen column were shown to produce local gravity over-ride of the injected CO2 and displaced hydrocarbon gas, thereby creating gravity tongues which resemble viscous fingers.
Use of CO2 additive to stimulate bitumen containing hydrocarbon solution gas under partially-depleted reservoir conditions was shown to decrease the bitumen recovery expected from application of steam alone. An encouraging observation is the deep penetration of the CO2 additive, which is expected to accelerate interwell communication and "condition" the reservoir for a steamflood.
Thermal Efficiency of a Steam Injection Test Well with Insulated Tubing
Authors: Aeschliman D. P. , Meldau R. F. , Noble N. J. 
Published: December 2007

Abstract
A field test of bare 2.375-in and insulated 4.500-in tubulars has been conducted using heat flux sensors and thermocouples to evaluate bare and insulated tubular performance, annulus heat transfer, and overall wellbore heat loss in a cooperative effort between Sandia National Laboratories and Husky Oil Operations, Ltd. The well is part of a steam flood pilot in the Aberfeldy Field near Lloydminster, Saskatchewan.
Insulation thermal conductivity was observed to vary by a factor of four between competing designs. Couplings and internal structures (e.g., centralizers) were seen to account for up to half the string heat loss with the annulus dry. For a wet annulus, the typical field case, steam generated at the hot couplings refluxed in the vented annulus and maintained the casing temperature constant at 212F at all points. Thus wellbore heat loss was 3-6 times higher than expected, the same opposite the highest and lowest quality insulated tubing, and only 30-40 percent less than bare tubing.
Insulated couplings or techniques to eliminate annulus steam refluxing are needed to achieve the potential of insulated tubing.
Deepwater Advanced Diving Systems That Support the Offshore Oil Field
Authors: Carnevale S. J. 
Published: December 2007

ABSTRACT
This paper reviews deepwater diving technology which provides offshore oilfield support during all phases of exploration, construction and production. Mobile Observation Bells (MOB), Atmospheric Diving Suits (ADS), Remotely-Operated Vehicles (ROV), and saturation diving techniques are discussed. The term "deep water" is defined in relation to the water depths off the U.S. west coast. All diving system parameters are analyzed for each alternative; cost-effectiveness and safety are the two main objectives. Specific jobs are described which have used this high technology equipment for offshore operations on the U.S. west coast. These include drilling rig support, platform inspection and maintenance, and pipeline construction. Finally, future developments in diving systems will be discussed.
Laboratory Measurements of Mechanical Properties of Sandstones and Shales
Authors: Senseny P. E. 
Published: December 2007

ABSTRACT
Laboratory tests were performed on specimens of sandstones, shales, siltstones and mudstones from thirty horizons in the Piceance Basin in support of the DOE Western Gas Sands Project Multi-Well Experiment. The objective of these tests was to determine tensile strength, compressive strength and elastic constants. Data obtained show that these properties vary substantially from horizon to horizon, and do not correlate well with either lithology or depth.
The Multiwell Experiment Core Program
Authors: Sattler A. R. 
Published: December 2007

ABSTRACT
The Multi-Well Experiment (MWX) is a research- oriented field laboratory and it is the major pro-duction technology activity of the Western Gas Sands Project. A major activity is the core analysis program. Over 3600 ft (1097 m) of core were taken from two wells separated by only about 110 ft (34 m) at depth. All major categories of core analysis are reviewed and results through December 1982 are included. Those include routine core analysis, restored state reservoir parameter measurements, electrical measurements, mechanical rock property data, mineralogy, organic maturation and geochemistry. This paper also describes the laboratory work on core and formation invasion and the development of instruments that were used in the field processing of the core.
Reverse-Phase Ion-Pair Chromatography (HPLC) of Alkylbenzene Sulfonates
Authors: Verkruyse L. A. , Lewis R. V. , Meyers K. O. , Salter S. J. 
Published: December 2007

Abstract
A high-performance, liquid-chromatographic procedure is presented that rapidly and quantitatively separates alkylbenzene sulfonates according to their alkyl chain length and structure. The separation employs octadecylsilanized silica gel as a stationary phase and an aqueous acetonitrile solution of tetrabutyl ammonium chloride (TBAC) as the mobile phase. The TBAC acts as an ion-pair reagent and suppresses the ionic nature of the sulfonates. Separation is effected by gradients in TBAC concentration and mobile phase polarity. The concentration of each component is then quantitatively measured by a UV detector. Gradient selection and sample matrix effects are discussed. Several examples are presented that demonstrate the utility of this analytical procedure.
Gelatinous Oil-Base Fluids as Insulators in Geothermal and Oil-Recovery Applications
Authors: Son A. J. , Dzialowski A. K. , Loftin R. E. 
Published: December 2007

Abstract
The use of a thixotropic gelatinous oil-base fluid as an insulating medium in different oil field applications has become increasingly important. Its economic advantage over tubing/casing insulators makes it very attractive. It has proven itself as a successful thermal insulator in the field, particularly in steam injection projects. The data generated in the field, related to its thermal characteristics, are difficult to correlate because so many variables exist from well to well. This investigation was undertaken to define some properties, under more controlled conditions, that would promote more efficient utilization of the thixotropic gel. Heat transfer coefficients were generated so that its efficiency as an insulator can be rated relative to other insulators. Thermal expansion coefficients, derived in the study, are much needed in engineering calculations such as volume requirements, tubing/casing strength, etc. Behaviour of the insulating gel at 700°F and 10,000 psi and static gel strength at various temperatures were also determined to answer questions on temperature limitations and pressure requirements for placement and displacement.
Selective Gas Shut-Off Using Sodium Silicate in the Prudhoe Bay Field, AK
Authors: Herring G. D. , Milloway J. T. , Wilson W. N. 
Published: December 2007

Abstract
To alleviate excess gas production in the Prudhoe Bay field, a non-rig gas shutoff technique using sodium silicate has beer-developed. An activated sodium silicate mixture is squeezed through coiled tubing into the gas producing intervals where it gels into a gas impermeable barrier. In addition, a temporary bridging agent has been successfully used to isolate oil producing intervals during a squeeze. This technique utilizes coiled tubing and can be accomplished for approximately 25% of the cost of a standard rig workover at Prudhoe Bay.
Pressure and Temperature Effects on Brine Completion Fluid Density
Authors: Thomas D. C. , Atkinson Gordon , Atkinson B. L. 
Published: December 2007

Abstract
A model has been developed to predict the density of a brine containing CaCl2, CaBr2) and ZnBr2 from its composition. The model accounts for the effects of pressure and temperature using experimental results and literature data. The theoretical framework and equations used are presented.
Brine completion fluids are used to control wells during gravel-packing and other open perforation completion work. Since they are usually filtered to minimize particulate invasion, careful adjustment of the overbalance pressure is required to minimize fluid loss to the formation. The methods presented here will allow the engineer to more accurately estimate the density requirements for the fluid.
The model has been compared to published brine density data and matches that data well. The model predicts the effects of temperature on CaCl2, CaBr2 and ZnBr2 solutions. The effect of pressure on these fluids is small and less documented, but where data are available for comparison purposes the model matches the data well up to 200°F.
Methods of predicting the density of brine completion fluids are needed for well control pressure calculations and cost control of fluids, and are major factors in brine completion fluid optimization. This work represents the first application of modern solution thermodynamics to field completion brine problems.
Modeling of Asymmetric Vertical Growth in Elongated Hydraulic Fractures and Application to First MWX Stimulation
Authors: Palmer I. D. , Craig H. R. 
Published: December 2007

ABSTRACT
When a continuous sand is bounded by zones of higher, but unequal, minimum in-situ stress, a vertically asymmetric hydraulic fracture results. The modeling is much more difficult than in the symmetric case mainly because the width equation is harder to formulate and solve. In this paper we present the principal components of the modeling, which includes non-Newtonian flow, leakoff with spurt loss, and "storage" of fluid due to volume expansion. The assumption is that the fracture is highly elongated, i.e., stress contrasts between pay and bounding zones are relatively large (≳ few hundred psi). Vertical gradients of minimum in-situ stress and fluid pressure can be included in the modeling. To illustrate, the results, we present design calculations for a 30,000 gallon fracture, which was the first stimulation in the Multi-Well Experiment. The 80 ft fracture interval in the Paludal zone has at its upper edge a 520 psi stress contrast, and at its lower edge a 1195 psi contrast. Computed fracture height growth above and below the perforated interval, bottomhole pressure, and width profiles in vertical sections are displayed. Comparison is made with diagnostic measurements of fracture length, height, and bottomhole pressure.
Aqueous-Based Fluids for Perforating and Oil-Phase Mud Removal
Authors: Goode D. L. , Stacy A. L. 
Published: December 2007

ABSTRACT
Wells drilled with oil-phase muds are subject to severe damage due to loss of mud filtrate or whole mud to the reservoir matrix or hairline fractures. It is essential that this mud be removed prior to well production in order to gain maximum productivity. Because of the severity of this mud damage and the ineffectiveness of conventional treatments, a system of aqueous-based remedial treatments was developed to remove oil-phase drilling muds from damaged reservoirs. Mud solids are suspended and mud viscosity is permanently lowered by the aqueous-based system so that the mud can be flowed to the surface. Special surfactants restore the affected rock surfaces to a water-wet state. The system can also be formulated in high-density brines for spotting and perforating. The system's thermal stability enables it to be used for extended periods of time at elevated temperatures.
The aqueous-based system represents an improvement over conventional hydrocarbon/mutual solvent treatments. The conventional treatments do not effectively suspend mud solids and only temporarily reduce mud viscosity, while leaving the treated rock surfaces in an oil-wet condition. In addition, hydrocarbon-based fluids require substantially higher pressures for placement in the well than the aqueous-based system.
Laboratory data are presented showing the relative effects of the aqueous-based system and a conventional hydrocarbon/mutual solvent treatment on the degree and permanence of oil-phase mud viscosity reduction. The aqueous-based system more effectively and irreversibly lowers mud viscosity, as compared to the hydrocarbon/mutual solvent treatment. Cores damaged by oil-phase mud filtrate or whole mud were treated with either hydrocarbon/mutual solvent or the aqueous-based system. Regained core permeabilities following the treatments indicate that the aqueous-based system yields significantly higher permeability recoveries than the hydrocarbon/mutual solvent treatment.
The aqueous-based system has been widely used in wells drilled with oil-phase muds to effect significant production increases. These remedial treatments have more effectively removed damaging oil-phase mud filtrate and solids than conventional hydrocarbon/mutual solvent treatments.