bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Stimulation-Sand Control Method
Authors: van Poollen H.K. , Malone W.T. 
Published: December 2007

Abstract
The authors have suggested explanations for the occurrence of sand problems, which include stresses due to drilling, initial formation stresses, and formation fluid pressures. These stresses combined result in rock failure immediately adjacent to the wellbore. This, in turn, leads to a plastic or semi-plastic state of stress, which will cause rock to flow into the wellbore due to mechanical stresses. In addition to the mechanical stresses, those developed due to viscous drag tend to move formation particles into the wellbore.
The authors suggest a possible explanation of wellbore damage peculiar to sand problem wells.
Two methods of sand control are briefly described. In the first method, a sheath of sand is formed adjacent to the wellbore serving as a screen for particles moving toward the wellbore, and a bridge over the performations or liner slots. The second method includes the creation of lenses or fractures prior to placing the sheath. These lenses or fractures are believed to be formed by high rates of injection due to the dilatant characteristics of sand problem formations.
From a production standpoint, the particle size in the sheath or pack is of no importance as References and illustrations at end of paper long as it has a higher permeability than the formation. It would appear, therefore, that the size of the packing sand should only need to be determined by its bridging and screening capacity. Both methods result in stimulation of a well; however, it is pointed out that the method using both fracturing and packing appears definitely superior.

Introduction
In certain areas, particularly in the Gulf Coast and California, formation sand is produced with the oil. The amounts of sand produced cause both production and disposal problems.
To keep the formation sand in place, graded sand is frequently pumped into the wells and packed behind the casing, a liner or a screen. As much as 97,000 lb of sand have been used in a single treatment. The sand is pumped into the well in a fracturing fluid in concentrations of about 2 lb/gal. The process of sand packing dramatizes the possible existence of a plastic or semi-plastic ring surrounding the wellbore.
Two main methods have been used for the placement of the packing sand. One method assumes that the unconsolidated formation will compact or compress and allow the packing sand to build in concentration immediately adjacent to the wellbore. Usually pressures are not allowed to increase rapidly throughout the process.
A Strong Transfer Function Links Thin-Section Data to Reservoir Physics
Authors: Ehrlich R. , Horkowitz K. O. 
Published: December 2007

ABSTRACT
Petrographic thin sections carry considerable precise quantitative information concerning physical properties including permability, log response and acoustic phenomena. This information is not carried by conventional pétrographie procedures such as point-counting or simple linear measurements made with a graduated ocular. Instead, multispectral image analysis techniques are required. Critical parameters of such a system include: 1) selection of correct magnification; 2) selection of proper spectral bands; 3) construction of a high precision digital filter able to precisely define grain and pore boundaries at the upper surface of the section; 4) an algorithm to express in useful fashion the complex geometries of grain and pore as well as correctly identify minerals and mineral phases; and 5) software to analyze such data. Output data is copious -- for example, over 300 variables describe estimation of such properties as permeability and identification of pore characteristics associated with enhanced or reduced permeability.
Price Forecast for Energy Lending
Authors: David A. , Carson G. P. 
Published: December 2007

ABSTRACT
The movement of world oil prices continues to be a topic of interest and concern. While political forces are a factor in price projections, banks primarily use the long term oil supply and demand situation as the underlying support for making oil and gas price projections.
Last year, price fluctuations and the uncertainty associated with price forecasts caused banks to follow their lending policies more closely and to become more prudent in their lending guidelines by assigning more risk to nonrevenue producing reserve categories. However, the ability of banks to lend against collateral composed of oil and gas reserves has not decreased.
Thirty energy banks were surveyed to determine how they assign loan values and to compare their pricing and loan assumptions. The most notable change from last year's survey is that most banks have lowered their price escalation projections. Although the banks' lending policies for proved producing reserves remain similar to previous years, uncertainty regarding future prices and its associated risks for nonproducing and undeveloped properties increased.
This paper compares the banks' pricing assumptions, and shows how price variations can have dramatic effects on loan value. This paper also compares the 1983 survey results with the previous two years.
Paraffin Inhibition Treatments Reduce Well Maintenance Costs
Authors: Charles J. G. 
Published: December 2007

Abstract
In many oil producing areas, paraffin deposition on downhole tubulars can present serious production problems. There are currently many methods available with which to try and solve or lessen the severity of these problems. Although it seems no one solution has a very large area or number of wells with which it remains efficient. A new patented process now has the ability to treat wells in many different areas and formations, and yield excellent results. This apparently universal application can save long periods of trial-and-error testing in an attempt to find a solution to each well's specific paraffin problem.
New Stimulation Technique Improves Frac Recovery and Increases Production
Authors: Phillips A. M. , Wilson W. J. 
Published: December 2007

Abstract
A technique for improving stimulation fluid recovery has been developed in the laboratory and has proven effective in field applications. The method involves improving proppant pack drainage and minimizing capillary pressure in the formation through the judicious application of surface active agents.
The technique is particularly applicable in low pressure oil wells and tight gas reservoirs, and may be used in all aqueous fracturing treatments. These include slick and gelled water, as well as foamed and crosslinked systems. The technique involves the use of a solvent in the pad fluids and a surfactant system throughout the entire fracturing treatment. This combination improves sand pack drainage and minimizes capillary water blocks in the invaded formation, while maintaining the water-wet condition of both the proppant pack and formation.
The results of field applications using this technique have shown great improvement in the recovery of aqueous stimulation fluids in both sand and limestone formations. Increases in initial hydrocarbon production have also resulted. Case histories are presented from both oil and gas wells in a variety of formations.
Simplified Approach to Air Drilling Operations
Authors: Puon P. S. , Ameri S. 
Published: December 2007

Abstract
Traditionally, air requirements during an air drilling operation involve the utilization of the Angel's chart(s). The values from the mentioned chart(s) are generally 20-25% below the acutal field's requirements/needs. Recent studies in this area have provided more reliable results, however, the tedious calculations, the lack of proper charts, and the absence of the user-friendly programs have prevented their practical applications. The authors of this paper have developed a simplified model that takes into account both the material balance and momentum balance for the annulus. Air and cuttings have been treated independently in these balances. Multiphase momentum balance equation is adopted. This model will also accommodate the air lifting capacity in the annulus to be the dominant factor in deciding the air requirements.
The Operator-Contractor Relationship—Gains and Losses, 1982 to 1984
Authors: Chiles W. E. 
Published: December 2007

ABSTRACT
Q. Have drilling costs decreased? How was this obtained – better efficiency or price cuts? A. Since we are in the offshore drilling business I can only speak in terms of the offshore industry. Drilling costs for the offshore operators have decreased approximately 35-45% since January, 1982 when utilization rates and dayrates began to fall significantly which continued until September, 1983. Although a large part of the decrease in costs can be traced directly to price reductions in all goods and services used in drilling, some of the reductions have been as a result of better efficiency on the part of drilling contractors, operators, and other service companies. Turnover is way down and we've had time to do a better job of training our personnel. In fact, during these lean years, we have appreciably increased our training budget to take advantage of this situation so that we will be in a better position when we start graving again. I think that we can all say that we have much more qualified personnel offshore today than ever before. Drug usage seems to be down also. Q. Has productivity improved? Where did it come from – the operator, the contractor, or both parties working together? A. As stated above, efficiency has improved across the board, and this is largely due to better qualified and trained personnel. However, operators and contractors are finally learning that their relationship is not an adversary one and that teamwork is the key to getting a well drilled in the least amount of time at the lowest cost. For years, we've had a situation offshore where there was a continuing battle over who was going to be on top of the heap – the operator's representative or the contractor's toolpusher. Egos were the important thing and the well would get drilled anyway. This situation could not be tolerated and is gradually changing by better training in basic supervision and management. Everyone is finally realizing that we are all cut there for the same reason – to safely drill and/or complete a well in the least possible time and cost. Once this objective has been established and is clear in everyone's mind, the next step is total cooperation and teamwork from the planning stage all the way through moving the rig off location. Q. What has been the effect of price cuts on quality of service, downtime, maintenance, safety and training? A. I can only speak about our company. We have not reduced our level of service one bit. In fact, we feel that it has never been better. Our crews are better, our rigs are in the best shape ever, and our safety record has improved significantly. We made a commitment when the downturn hit to cut costs only in areas that would not affect our level of service nor would cost us dearly down the road.
The Operator-Contractor Relationship—Gains and Losses, 1982 to 1984
Authors: Johnston R. E. 
Published: December 2007

ABSTRACT
The boom and bust days of the period between 1979 and 1983 was a very painful period for the Oil and Gas Industry. A mania seemed to grip the entire industry! The feeling was that the boom was here to stay, would last forever, and tomorrow would never come. Unfortunately, this thinking and prevailing outlook brought about many unfortunate situations. Operators felt that with oil and gas bringing premium prices, unusually high lease costs were economically justifiable as well as inordinate high drilling costs and elevated equipment costs. In the thinking of most operators nearly every lease had to be drilled as quickly as possible, and if production was established the wells had to be placed on production with an absolute minimum of delay.
Then the "bust" came. Led by the Penn Square Bank debacle and later the natural gas pricing turning soft, activity hit bottom in an almost unbelievable short period of time! Suddenly the industry was faced with a giant oversupply of drilling rigs, service companies, and equipment.
Jackup Rig Designs for Environmentally Sensitive Areas
Authors: Chiles W. E. , Cochran T. J. 
Published: December 2007

ABSTRACT
As the search for oil and gas moves into more environmentally sensitive areas, and State and Federal regulations with respect to waste discharges are becoming more restrictive, it is imperative that offshore drilling contractors design and build drilling units fully capable of meeting the most stringent regulations. All operating parameters must be examined so that any potential source of pollution or waste discharge has been identified and prevented, including, in certain instances, the collection and safe discharge of rainwater runoff. The systems designed to accomplish the above must be cost effective, simple, and must not adversely affect the drilling operation.
Elastic Yield of Casing Due to Elevator/Spider System
Authors: Hayatdavoudi A. 
Published: December 2007

ABSTRACT
Through many simulated experiments, it has been found that the casing will yield prior to its being run in the hole. The yield is generally due to the high radial and friction side loads imparted to the casing by slips in the spider/elevator system. In order to reduce the occurrence of high magnitude of the hoop strain and possibly the yield of the pipe, the stiffness of the inserts has been changed by incorporating an "insert backing" material into the slip system. This reduces stored energy into the pipe. Furthermore, the optimum FRIMB load (Friction and Imbedment Load) per tooth of inserts and the insert tooth spacing have been found. In order to facilitate the analytical solution of cylindrical shells, a much-needed function previously not available has been generated experimentally.
Invert Oil Mud Rheology as a Function of Temperature and Pressure
Authors: Politte M. D. 
Published: December 2007

ABSTRACT
There is a need in the drilling industry to be able to predict the viscosity of oil muds as a function of temperature and pressure. This paper presents the results of an experimental investigation into invert diesel oil emulsion mud viscosity and how it is affected by downhole conditions. Results are given from tests on diesel oil, brine, low colloid oil-brine emulsions, and low colloid muds ranging in density from 10-18 ppg.
It was found that invert oil muds generally behave like Bingham plastics. The plastic viscosity can be normalized with the viscosity of the continuous phase, and can therefore be predicted as a function of temperature and pressure. The yield value is only weakly affected by pressure, while the temperature dependence depends upon the amount of solids and organophillic clay present, and the temperature/shear history. A method is given to estimate downhole plastic viscosity and yield value based upon surface measured values.
Results of example calculations are given which show that the use of variable plastic viscosity in friction pressure loss calculations makes little difference in most cases, and that the calculations are not very dependent upon the base oil used, whether diesel or one of the less toxic oils.
Drilling Performance: The Struggle to Improve
Authors: Hough R. B. , Coumans H. 
Published: December 2007

ABSTRACT
During the past three years, an intensive exercise has been underway in Shell Expro to improve the drilling performance in its fields Brent, Cormorant, Dunlin and Fulmar, and on mobile rigs. Expro approached this by concentrating on its primary resources: Men, Materials and Methods. The emphasis has been on trying to improve motivation, committment and knowledge by all involved in the operation, to try out new techniques and equipment where such are identified as being potentially beneficial, and to study procedures currently in use, with the object of improving the drilling efficiency.
Planning, Drilling, and Evaluating a Deep Wildcat in North Central Louisiana: A Case History
Authors: Scott D. G. , Dwiggins R. , Lynch K. W. 
Published: December 2007

ABSTRACT
ARCO Oil and Gas Company and ARCO Exploration Company recently drilled and evaluated a 17,532 ft. wildcat twelve miles south of Natchitoches, Louisiana. This paper is a case history discussing the planning, drilling and evaluation of this well.
The planned stratigraphic selection of casing points proved vital to the elimination of lost circulation and was the key to the relatively trouble free drilling of the well. Rig selection, with emphasis on good bit hydraulics, resulted in penetration rates with 12 1/4 in. bits that equaled or exceeded those of the smaller bits used in offset wells. A low colloid, high temperature stabilizer mud system performed well in the presence of CO2 contamination at a bottom hole temperature above 400° F.
The well was evaluated in production casing with the rig in place using rented tubing, a retrievable packer, and a surface drill stem test manifold. Reservoir content was determined at a reduced capital cost. The stimulation and well control limitations of this assembly are discussed.
Measuring the Wear of Milled Tooth Bits Using MWD Torque and Weight-on-Bit
Authors: Burgess T. M. , Lesso W. G. 
Published: December 2007

ABSTRACT
A bit torque relationship based on a force balance concept has been proposed by Warren1. The relationship shows that for a given bit, the torque is determined by the applied weight-on-bit and the depth of tooth penetration. This paper extends the torque model for soft formation milled tooth bits to show how the effects of tooth wear can be taken into account. The method is intended for formations like shales that are drilled by a gouging and scraping action.
An interpretation technique, based on the model, is developed. It is called the Mechanical Efficiency Log (MEL)TM. It uses time averaged values of penetration rate, rotation speed, and measurements while drilling (MWD) values of torque and weight-on-bit. The result of the interpretation is real time calculations of tooth wear, drilling efficiency, and the in situ shear strength of the rock.
The Extension of the Variable-Flux-Weighting Method to Multidimensional Problems Including Gravity and Capillarity
Authors: Lasseter Thomas J. 
Published: December 2007

ABSTRACT
The variable-flux-weighting method has been shown to largely eliminate numerical diffusion at saturation discontinuities in two-phase flow in two-dimensional problems1. The method has been extended to multidimensional problems including gravity and capillarity. The method is derived from fractional flow theory and involves the computation of a variable weighting factor for the interface fractional flow between grid blocks. In order to eliminate numerical diffusion at shocks, the appropriate weighting has been found to be downstream weighting just ahead of the shock and upstream weighting otherwise.
In one-dimension, the saturation distribution for two-phase flow including gravity has been solved and compared with the analytical solution. The comparison is very good with no numerical diffusion apparent at the saturation discontinuity. Problems including capillarity nave also been solved. In this case there is no saturation discontinuity, but the method introduces downstream weighting at the upstream edge of the capillary fringe which effectively eliminates any significant numerical diffusion.
Two- and three-dimensional problems have also been solved which demonstrate the accuracy of the method. For three-dimensional problems, the current implementation of the VFW method is ten times slower than an upstream-weighting IM PES method.
A Finite Element Formulation of the Two-Phase Flow Equations for Oil Reservoirs
Authors: Gulbrandsen S. , Wille S.Ø. 
Published: December 2007

Abstract
In the present paper, the differential equations governing two phase, immiscible flow in porous media is solved by the finite element method.
The saturation of the wetting phase (water) and the non wetting phase (oil) have been used as independent variables. In this finite element formulation the saturation and pressure equations are solved simultaneously and the formulation is entirely implicit. The time derivatives are approximated by backward Euler differences. The Newton Raphson method is applied to solve the non linear equations.
The differential equations are solved in the original form without simplifications. The simulations are performed in a two dimensional model, but the algorithms will have equal advantages in three dimensional simulations. The results of the simulations are presented as saturation and pressure isocurves, and velocity vector field.
The Chemistry and Design of Scale Inhibitor Squeeze Treatments
Authors: Meyers K. O. , Skillman H. L. 
Published: December 2007

ABSTRACT
The deposition of scale in the near-wellbore formation and production string can result in a significant decrease in well capacity. Correctly designed scale inhibitor squeezes can successfully prevent scale deposition and the corresponding productivity declines. However, inadequate knowledge of the chemistry of the scale inhibitor and its interactions with the formation can yield ineffective squeezes. Inappropriately designed squeezes may actually damage the formation.
This paper addresses the chemistry of phosphonate scale inhibitors and the application of that chemistry in inhibitor selection and squeeze design. Screening/design criteria discussed include scale inhibition, thermal stability, corrosivity, scale dissolving capability, solubility in the reservoir brine, compatibility with multivalent cations, and adsorption/desorption on the reservoir rock. These criteria are illustrated with the results of an inhibitor screening study for the Prudhoe Bay field. Laboratory and field results illustrate how inhibitor chemistry can be used to optimize squeeze design.
Alumina Gel Drilling Fluid for High-Temperature Use
Authors: Block J. 
Published: December 2007

ABSTRACT
A new clay-free drilling fluid has been developed for use at temperatures up to at least 177°C (350°F). The fluid consists of an alumina gel (pseudoboehmite) viscosifier stabilized with various bulky anions. These bulky anions include inorganics, such as sulfate, and organics, such as tartrate and citrate. Filtration control is provided by a compatible cross-linked poly(vinyl alcohol). The fluid is highly shear-thinning (the n value in the power law model is less than 0.3), has shale stabilizing properties (based on laboratory tests with sodium bentonite and various shales), is divalent ion tolerant, and can also tolerate moderate NaCl levels.
The system has been successfully field tested in a deep well (4,823 m (15,824 ft) total depth) in western Oklahoma. Good properties were maintained through both the unweighted and weighted portions of the well. Penetration rates and rig utilization rates were compared with an offset well drilled with a dispersed bentonite mud, and the trends were favorable. If further field tests confirm laboratory data, this new mud system should be able to delay (or eliminate in some cases) the conversion to oil based muds.