bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of a Heavy-Oil Recovery Process by an Immiscible CO2 Application, Bati Raman Field
Authors: Karaoguz D. , Issever K. , Pamir N. , Tirek A. 
Published: December 2007

ABSTRACT
Batl Raman oil field, with its 1.85×109 STB oil in place and poor primary recovery (1.5% of IOIP) was a good target for enhanced oil recovery.
As a result of extensive laboratory, modeling and comparative engineering studies, TPAO has decided that an immiscible type CO2 application would be the most suitable method to enhance the recovery from the field.
Initially planned "huff and puff" has now turned to a successfull CO2 flood.
Around 2×106 STB of incremental oil have been produced, since the project resumed continous operation in late 1986. With daily production increase reaching over 4000 STB, and still having an increasing trend, the project looks promising.
Hydrocarbon Potential of Palaeozoic Pre-Khuff Clastics in Abu Dhabi, U.A.E.
Authors: Ali A. R. , Silwadi S. J. 
Published: December 2007

ABSTRACT
The Palaeozoic pre-Khuff sedimentary section in Abu Dhabi proved to be a new attractive area for hydrocarbon exploration. It is mainly composed of a continental-fluvial/deltaic sandstones, siltstones, shales and subordinate claystones and dolomite of Permo-Carboniferous and Devonian (and older) age. An unconformity surface (at least Haitus) could be defined at 461 to 675 ft. below the top of the pre-Khuff clastics which might mark the latest phase of Hercynian tectonics, separating the Devonian and older rocks from the Permo-Carboniferous clastics.
Depth of the pre-Khuff clastics range between 14730 ft. SS. and 19588 ft. SS. in Abu Dhabi. Maximum sections of pre-Khuff clastics penetrated in wells; Hair Dalmah-3, Shah-16 and Satah-19 were 803, 1464 and 1508 ft. respectively.
Palynological analysis, lithofacies and log response, broadly allow the dividing of the pre-Khuff clastics into two main lithostratigraphic units; pre-unconformity unit (Devonian and/or older – more than 900 ft. thick) and post– unconformity unit (Permo-Carboniferous – 461 to 675 ft. thick). The succession could also be subdivided into four reservoir units; three of them (PK-1, PK-2 and PK-3) are gas bearing in Hair Dalmah-3 and the fourth (PK-4) is highly deteriorated in Satah-19 and Shah-16. The reservoir units PK-1, PK-2 and part of PK-3 in Hair Dalmah are within the post-unconformity lithostratigraphic unit, whereas the rest of PK-3 and PK-4 represent the pre-unconformity lithostratigraphic unit.
The pre-Khuff clastics are generally characterized by poor to fair porosity and low matrix permeability. Porosity types are mainly of primary origin and controlled by original depositional facies, depth of burial and diagenesis. Fractures are rarely defined in the section and have no significant impact on the porosity and permeability.
Production from the Palaeozoic pre-Khuff is mainly free hydrogen sulphide gas. The main gas component is Methane which forms about 69% of the total pre-Khuff gas composition, however, appreciable amounts of Nitrogen (about 23%) and Carbon Dioxide (about 8%) were also encountered.
The source of the hydrocarbon gas in the Palaeozoic pre-Khuff clastics is most probably the Silurian shale which is regionally defined over the Arabian Peninsula and the Arabian Gulf area (not penetrated in any of Abu Dhabi deep wells), however, geochemical analysis of the uppermost pre-Khuff clastics (about 50 ft. of shales and siltstones) in some localities of Abu Dhabi have indicated that this shale is of poor to moderate source potential.
Pilot Waterflood Evaluation - Panhandle Field
Authors: Henry J.C. , Moring J.D. 
Published: December 2007

American Institute of Mining, Metallurgical and Petroleum Engineers, Inc.
This paper was prepared for the Society of Petroleum Engineers of AIME, Regional Secondary Recovery Symposium, to be held in Pampa, Tex., Oct. 26–27, 1967. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copies. The abstract should contain conspicuous acknowledgement of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
In July, 1963, a five-spot pilot water-flood was initiated in the Brown Dolomite of Skelly Oil Company's Schafer Ranch lease in the Panhandle Field, Carson County, Texas.
Two years later response had not yet occurred even though 1,300,000 barrels of water had been injected. Injectivity surveys indicated that the water was entering the producing formation at the well bore but what happened to it after that remained a mystery.
A decision was made to find out if the water was actually staying in the formation. This was to be done by drilling a test well half way between one of the four injection wells and the center production well.
Analysis of test data indicated that the advance portion of the flood front had already passed this position and must be close to the center producing well. The flood was behaving admirably - water was going into the formation and not channeling. Fracture treatment of the center producing well resulted in the long-awaited response.

Introduction
This paper is about an evaluation of a pilot waterflood. However, it is not a theoretical evaluation based on hypothetical data. It is based on actually drilling a well in the middle of a pilot, coring, logging and testing it, and then analyzing this data. We did what many of us that try to deal in abstract reservoir engineering would love to do. In effect, we went down and took a chunk out of the reservoir while it was in the process of being flooded.

PANHANDLE FIELD
The pilot (Figure 1) is located in the Texas Panhandle Field: the second largest field in terms of cumulative production in the United States. Only the East Texas Field is larger, with a cumulative production of 3.7 billion barrels compared to the Panhandle Field's 1.2 billion barrels. This field is over 100 miles long and extends into five counties. Just to the south of the field is a buried granite mountain ridge, called the Amarillo Mountains, which extends into Oklahoma where it becomes the Wichita Mountains.
Fully Computerized BHA Analysis Significantly Improves Directional Drilling Performance
Authors: Gibson M. T. 
Published: December 2007

ABSTRACT
Texaco North Sea UK Co significantly improved directional drilling performance on their recent ‘S’ shaped Highlander development well by utilising four specialised computer programmes.
By analysing the performance of every past BHA run on previous Highlander directional wells, it was possible to design idealised assemblies prior to spudding the well. The in-field performance of the designed BHA's was then optimised by use of an on-site computer system.
Upgraded Semisubmersible Drilling Rigs Set a New North Sea Standard
Authors: Bearne M. C. 
Published: December 2007

ABSTRACT
Two heavy duty North Sea semi-submersible drilling units have been enhanced by the installation of additional buoyancy chambers and upgraded drilling equipment. This relatively recent investment in the rigs has improved drilling performance. It also means that the future challenge of an increasingly demanding North Sea exploration programme can be tackled with both confidence and vigour.
Enhanced Oil Recovery by Wet In-Situ Oxygen Combustion: Esperson Dome Field, Liberty County, Texas
Authors: Pebdani F. N. , Longoria R. , Wilkerson D. N. , Venkatesan V. N. 
Published: December 2007

ABSTRACT
A field test of wet in-situ oxygen combustion has been carried out in the Esperson Dome field in southeast Texas. The objectives of the pilot test were to evaluate the potential of oxygen combustion technology, to assess its advantages over air fireflooding, and to gain experience in the safe handling and downhole injection of high purity oxygen in an oil field environment.
The Miocene sandstone chosen for the pilot is relatively deep (2700 feet), thin (20 feet), and had been substantially watered-out by a strong natural water drive. At the beginning of the combustion pilot an estimated 850 bbl/acre-ft (36% saturation) of 90 cp (21 °API) oil remained in place. The natural water drive dominated the combustion process and assisted in displacing the oil. At project termination, 200 MMscf of oxygen and 55 MMscf of nitrogen had been injected, 90,000 barrels of oil recovered, four existing older wells failed, four new wells drilled, and three wells burned out. Determination of incremental oil is uncertain due to these operational changes.
The objectives of the project were met, and improvements in the project design and operation are expected to lead to an economic process for further applications.
Two-Phase Flow Through Porous Media: Effect of an Adsorbed Polymer Layer
Authors: Zaitoun A. , Kohler N. 
Published: December 2007

ABSTRACT
Polyacrylamide and polysaccharide adsorption on natural water-wet sand and sandstones is shown to modify markedly the flow behavior of both water and oil. At residual oil saturation, the quantity of adsorbed polymer per gram of rock is found to be almost the same as at full water saturation, but the permeability reduction to water is increased by the presence of trapped oil droplets which reduce the flow cross-section for the water phase. The presence of adsorbed polymer always induces an increase in the water irreducible saturation due to polymer hydration water which is not expelled by contact with oil. However the oil relative permeability is shown to be little affected by adsorbed polymer over the remaining saturation range. On the basis of a capillary two-phase flow model, this phenomenon is interpreted as the result of the competition between the reduction of flow cross-sections and the enhancement of the water-wettability of the rock, with both effects having the same origin, i.e. the polymer adsorption process.
The Influence of Rheological Properties on Mobility Control in Polymer-Augmented Waterflooding
Authors: Allen E. , Boger D. V. 
Published: December 2007

ABSTRACT
One of the major restrictions to increased oil recovery from reservoirs is poor sweep efficiency, caused by an interfacial instability phenomenon termed "viscous fingering". This paper reports the results of an experimental study into viscous fingering in two-phase flow, using a one metre diameter Hele-Shaw cell. Newtonian and non-Newtonian fluids were tested, including shear-thinning and ideal elastic (Boger) fluids. The viscous fingering patterns exhibit fractal behaviour, which enable both characterisation of the displacement pattern and extrapolation to larger scales.
Rheological properties can have a significant influence on the viscous fingering pattern and thus on sweep efficiency. Shear-thinning fluids exhibit significantly increased interfacial instability, especially at the rear interface with the chasing waterflood. Elastic properties have a negligible effect on the macroscale development of viscous fingers, but may have an important role at the microscale, by modifying the viscosity ratio for flow in porous media. Results to date suggest that the greatest improvement in sweep efficiency for EOR polymer flooding may result from the development of a pusher fluid with viscoelastic non-shear-thinning properties.
An Analysis, Of Single Point Entry And Fracture Plane Control
Authors: Clark Roscoe C. , Bucy B.J. 
Published: December 2007

PUBLICATION RIGHTS RESERVED
This paper is to be presented at the 36th Annual Fall Meeting of the Society of Petroleum Engineers of AIME in Dallas October 8–11, 1961, and is considered the property of the Society of Petroleum Engineers. Permission to publish is hereby restricted to an abstract of not more than 300 words, with no illustrations, unless the paper is specifically released to the press by the Editor of JOURNAL OF PETROLEUM TECHNOLOGY or the Executive Secretary. Such abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in JOURNAL OF PETROLEUM TECHNOLOGY or SOCIETY OF PETROLEUM ENGINEERS JOURNAL is granted on request, providing proper credit is given that publication and the original presentation of the paper.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and considered for publication in one of the two SPE magazines with the paper.

Abstract
"Single point entry" is rapidly becoming a conventional well completion technique when a well is to be stimulated by hydraulic fracturing. Along with this, the concept of "control of fracture planes" is becoming acceptable. As a practical matter, the two concepts are almost inseparable.
For years we have searched for ways and means for controlling oil reservoirs (i. e. getting them to produce oil the way we want them to). Hydraulic fracturing, and more particularly, CONTROLLED hydraulic fracturing, is a good long stride in this direction.
There is little argument against the two concepts. Considerable well data supports the desirability of creating as much fracture AREA AWAY from the well bore as possible and as much fracture CONDUCTIVITY as possible near the well bore. Statistical data now substantially supports that fractures can be controlled to the plane de sired a high percentage of the time - possibly as high as 75%. Skeptics of controlled fracture planes, however, have little to lose if they do believe in the advantages of single point entry. The worst failure that can be expected from attempted fracture plane control is simply an uncontrolled fracture. This result is assured if no attempt is made to control the fracture plane.
Single point entry completions offer the following substantial advantages:Greatly minimizes the chances for communication between zones. This is due to the longest amount of blank space possible between perforated intervals. Also, laboratory and field data collaborate in indicating that many cases of communication are caused by initiation of vertical fractures. These may occur up the cement column and/or in the formation adjacent to the bore hole.Excellent opportunity to retain all the fracture area in the producing zones.
Economic Factors Controlling Drilling Activity
Authors: Woods T. J. 
Published: December 2007

ABSTRACT
Over the past 40 years, U.S. drilling activity has fluctuated substantially. Over this period there have been some significant changes in price or in U.S. energy policy to prevent or allow price changes. As a result, a substantial body of theory has grown up to relate oil and gas prices to drilling activity.
However, a detailed analysis of drilling activity indicates that price, while important, often serves only as a proxy for the economic factors that actually affect industry activity. Energy policies regulating price, such as the Phillips decision regulating the wellhead gas price in interstate markets, have shown limited impacts on drilling activity. Regulations or market conditions affecting oil and gas production rates, however, have significantly affected drilling activity.
This paper assesses the periods in the past when there were significant changes in the level of industry activity to investigate the role that price has played in industry decisions. The analysis will consider periods during which activity has expanded and periods during which activity has declined. The analysis indicates that cash flow plus profitability, not price, dominate the industry's decisions. Thus, the mere increase or decrease in price is not sufficient to cause substantial changes in industry activity.
The Effect of Uncertainty in Petroleum Reserves Estimates on Hotelling's Economics of Exhaustible Resources
Authors: Stultz-Karim Sharon P. , Economides Michael J. 
Published: December 2007

ABSTRACT
The economics of exhaustible resources was employed in this paper to isolate the relationships between reserves estimates, time, and optimal pricing. A multilinear regressive technique was utilized to evaluate the statistical significance of the relationship of the independent variables of uncertainty in reserves estimates and time to the dependent variable of price. An idealized model of the international petroleum market was used as the basis of analysis and to develop theoretical statements regarding the affect of uncertainty in reserves estimates on petroleum pricing.
It was found that for reserves estimates made with uncertainty there was a statistical significance in its effect on pricing through time while reserves estimates made with certainty only time had a significant effect on pricing. Therefore, static commodity-based equilibrium methods of economic analysis are not adequate for the forecasting of future petroleum prices. Instead, price forecasting models must be dynamic and must incorporate reserves estimates that have been calculated with the most precise reservoir engineering and geological methodologies.
The Replacement Costs of Domestic Crude Oil and Natural Gas Reserves
Authors: Kuuskraa V. A. , Godec M. L. 
Published: December 2007

ABSTRACT
The costs of replacing domestic oil and gas reserves are today dramatically different than during the "boom" years of the early 1980s. Changes in costs, tax laws, and drilling efficiency have altered the outlook for oil and gas and thus have fundamentally revised least-cost supply strategies.
To provide a perspective on the new outlook, it is timely to re-examine the economics of finding and producing domestic oil and gas reserves. For this, the paper reviews recent data on domestic oil and gas expenditures, reserve additions, drilling costs and supply sources. The paper also examines the response of drilling costs to changes in oil prices, rig utilization, and technology.
The paper illustrates that least-cost reserve replacement will consider a supply portfolio that includes at least six sources: (1) undiscovered conventional oil and gas, (2) reserve growth from infill drilling, (3) oil (and particularly gas) from the deepwater OCS, (4) natural gas from low permeability sources (tight sands, coal seams and Devonian age shales), (5) enhanced recovery of heavy and light oil, and (6) expanded development of the North Slope of Alaska. Specific case studies of coalbed methane development in the Warrior Basin, infill drilling in the Permian Basin, and heavy oil steamflooding in the San Joaquin Basin provide examples of how various companies are pursuing their individual strategies.
Single Well Pressure Transient Testing in Prudhoe Bay, Alaska
Authors: Lockhart D. L. , Ogbe D. O. , Dehghani K. 
Published: December 2007

ABSTRACT
This paper presents the results of the application of a mixed-boundary pressure transient testing model to Prudhoe Bay wells. The proposed model considers a constant pressure upper boundary and a no-flow lower boundary. Reservoir anisotropy and partial penetration were considered in the model. These boundary conditions simulate the pressure transient testing in the Prudhoe Bay unit of the Alaskan North Slope where the oil column of the Sadlerochit formation is overlain by a huge gas cap.
A set of type curves for gas cap dominated data analysis is presented. These type curves should complement those presented by Kuchuk and Kirwan for no-flow upper and lower boundaries. A correlation for predicting the beginning of the constant pressure boundary effect is provided. This correlation can be used to estimate the period to record analyzeable early-time data during the design of a pressure transient test. Also, it is a useful tool for validating the results of type curve analysis of data obtained from gas cap dominated transient tests.
Examples of pressure buildup tests conducted in the Western half of the Prudhoe Bay unit are analyzed. The results obtained are used to discuss the problems of single well pressure transient analysis in gas cap dominated reservoirs.
Economics of Hydrocarbon Reserves in Overpressured Reservoirs below 18,000 ft in South Louisiana
Authors: Fertl Walter H. , Leach W. G. 
Published: December 2007

ABSTRACT
Abnormally high formation pressures, generally prevalent in south Louisiana at depths below 18,000 ft, significantly affect reservoir quality, magnitude of reserves, production characteristics and, hence, the ultimate recovery of those deep hydrocarbon resources.
At the time of this study, 515 south Louisiana wells had been drilled below 18,000 ft to Miocene and Oligocene target zones. Seventy-six wells, located in eight coastal parishes, were completed below 18,000 ft. A total of 146 wells were drilled as dry holes, in conjunction with these 76 completions, either on the same geological structure or in the same field. Of these 146 wells, 65 were dry holes and 81 had dry-hole footage below 18,000 ft. These 222 wells were selected as the basis for the economic evaluation.
The present investigation (1) relates formation temperature and pore pressure to the occurrence and recovery of oil and gas reserves, (2) discusses effects of porosity, permeability, irreducible water saturation, and gas compressibility, (3) illustrates the effects of overpressure on production behavior, depletion, final abandonment pressure, and ultimate recovery, and (4) presents the economical criteria in this deep-well environment.
Based on the above considerations, the resulting economical findings were statistically correlated to the well log-derived shale resistivity ratio (SRR). The SRR value is defined as the ratio of the predicted "normal" shale resistivity divided by the observed, "actual" shale resistivity.
In the present 222-well study, the probability of payout for a well is reduced by 80%, once the SRR exceeds 3.5. Concurrently, the chance of finding greater than one billion ft3 of equivalent-gas is also decreased by 80% once the SRR reaches 3.5. Statistically then, the SRR value, when applied to wells below 18,000ft in south Louisiana, can be used as an important input parameter for economic, managerial decision making. Such decisions may be made on whether to continue drilling, or reevaluate the entire deep drilling program in the geological area.
Field case examples, in-depth discussion of the various parameters, and a detailed review of all significant statistical results are presented.
The Use and Limitations of the Gamma Ray Spectroscopy Tool in a Middle East Carbonate Reservoir
Authors: Berta D. , Vermeulen C. C. L 
Published: December 2007

ABSTRACT
Several carbon/oxygen logs were run in many wells in a producing field to monitor fluid movement. The logs were run at the same time as a detailed reservoir engineering study was being performed, and this paper presents the most important conclusions.
Using the logs from a single well, and published information, the accuracy of the interpreted oil saturations was calculated as 23 saturation units (s.u.) at 20% porosity. The accuracy improves with increasing porosity.
The carbon/oxygen log's depth of investigation is not much farther than the borehole wall, in the area usually flushed by mud filtrate. Field evidence is shown to support the conclusion that interpreted oil saturations are often equivalent to flushed zone saturations calculated from shallow reading microresistivity devices. Evidence is also presented to show that mud filtrate has remained around the wellbore for as long as 30 years. As a consequence, the carbon/oxygen log is thought to have limited applicability in low permeability highly stratified reservoirs.