bluuebunny/crossref_metadata_2025_split huggingface dataset:
Practical Experience with Sand Control Completions in Vertical and Horizontal Wells, Bolivia
Authors: Escobar J. A. , Turner W. H. 
Published: December 2007

Abstract
This paper compares sand control methods used in vertical oil and gas wells with a relatively new method used in the first horizontal well drilled in Bolivia. Even though production from the horizontal well has not exceeded that from nearby vertical wells by the expected margin, initial results are encouraging. Production from a zone previously considered low yield has been at an acceptable level and through a larger choke than normally used in the area. The sand control method utilized may be extended to vertical wells.
Libertador Field: An Integrated Approach to a Development Plan
Authors: Graue D. J. , Larsen W. 
Published: December 2007

Abstract
An integrated study of the geology, petrophysics, geophysics, and engineering aspects was made on the Libertador field in Ecuador. The study began after the field had produced approximately 6% of the oil originally in place.
Data from geophysics, petrophysics, geology, transient pressure analyses, laboratory core analyses, and laboratory PVT analyses were integrated in a classical black oil simulation model to allow the evaluation of alternate development methods. A history match was performed on a model which incorporated all four of the principal producing sands. This study produced an evaluation which demonstrated that the highest recovery would be achieved using a combination of infill drilling water injection, and artificial lift.
Exploration/Development Strategy for Rio Caribe Field
Authors: Chalot J. P. , Gómez R. , Gonzalez F. 
Published: December 2007

AbstractThis paper presents the exploration/development of the Rio Caribe field, the new technological frontier of the Venezuelan oil industry. This field comprises 26 prospects extended on a surface of 101123 acres (405 Kms2) and is part of a giant gas and condensate field discoveries in north of Peninsula of Paria. The other fields are Mejillones, Patao and Dragon discovered as a result of the exploration campaign realized by Lagoven, S.A. between 1979-1983.The proposed strategy will be developed in several phases iniciated by an early development of the proved area and combined by an extensive effort of exploration. The very first exploitation scheme selected is recycling dry gas in order to maintain the well potential, to improve the recovery factor and to offer an early policy for the gas management.
A Comprehensive Theory of Transient Inertial Flow in Tubing, Skin Zone and Reservoir
Authors: de Swaan A. 
Published: December 2007

AbstractComplete analysis of well tests, from early to late time stages, is feasible with a model that includes in a single equation the effects of: a tubing composed by pipes of different diameters; chokes; segregated gas in the tubing; skin zone; reservoir geometry; and inertia of the flowing fluid.
Modelling Horizontal Wells in a Water Drive Reservoir: Guafita Norte Field, South Western Venezuela
Authors: Cordero F. J. 
Published: December 2007

Abstract
This paper discusses the results of a simulation study for horizontal well implementation in a reservoir with strong water drive, located in the Guafita Norte field in south-western Venezuela. The reservoir under consideration contains a 30° API (0.87 g/cm3) sub-saturated crude with a oil viscosity of 3.9 cp (3.9* 10−3 Pa.s) at 3,000 psia (20.68 MPa).
The well production evaluations were performed by 3D simulations using a numerical model.
Emphasis was made to study the effect of the drainhole length on production forecasts. The effect of vertical/horizontal permeability anisotropy and restriction of oil rate were also investigated.
Simulation results obtained for the horizontal well project can be considered as very encouraging. A 2,000 ft (609.6 m)long horizontal well would produce around 17 MMbbls(2.7*106m3)of oil over a 15 year period. This represents more than 30% of STOIP in the G-10 reservoir of the Guafita Norte field. A vertical well having a opened interval of 30 ft (9.14 m)would produce around 9 MMbbls (1.43* 106m3) during the same production period. Cumulative production forecasts show that production is not proportional to the drainhole length. However, a drainhole length varying from 1,000 to 2,000 ft (304.8 to 609.6 m) leads to an additional production of 2 MMbbls (0.32*106 m3) without dramatic water influx due to the well inclination.
Simulation runs also show a slight influence of the Kv/Kh ratio on the horizontal well production behavior.
Horizontal Well Applications and Parameters for Economic Success
Authors: Lacy S. , Ding W. , Joshi S. D. 
Published: December 2007

Abstract
This paper includes a review of horizontal well field histories and applications around the globe, with special emphasis on South and Latin American applications. The paper includes descriptions of economically successful, as well as unsuccessful horizontal wells in field applications. Results of the field histories are used to summarize essential parameters for economic success.
Horizontal wells have been used in: 1) thin pay zones, 2) naturally fractured reservoirs, 3) formations with gas and water coning problems, 4) heavy oil reservoirs, 5) gas reservoirs, and 6) enhanced oil recovery (waterflood applications, miscible floods, and thermal oil recovery).
Out of about 2500 horizontal wells drilled worldwide, almost 75% are drilled in the USA and Canada. In addition, most of the U.S. welts are drilled in a few formations, namely, Austin Chalk and Bakken Shale. Host of the U.S. applications are in low permeability (*1 md) reservoirs.
Outside the U.S., the majority of applications are for gas and water coning, mainly for water coning. These applications are in high permeability (400 md to 10 Darcy) reservoirs. In general, horizontal wells have a higher success rate in water coning applications than in gas coning situations.
Recently, horizontal wells have also been used in secondary recovery applications. Horizontal wells have exhibited excellent results in miscible CO2 floods. While application of horizontal wells in waterflooding shows great potential, application in thermal oil recovery shows mixed economic results.
The key parameters for success, based upon field results, appear to be: 1) fracture intensity, 2) hydrocarbon pay zone thickness, 3) well spacing, 4) vertical coomunication, 5) formation damage and post drilling clean-up ability, 6) geological control, 7) multiwell prospect, and 8) cooperation in geological, reservoir, drilling, and completion departments.
Reservoir Engineering Studies to Implement Additional Recovery Projects in El Furrial Field
Authors: Pizarro J. Herbas 
Published: December 2007

ABSTRACT
Reservoir engineering studies have been performed to aid in the definition, planning and implementation of a fluid injection project to increase the ultimate recovery and maintain oil production rates in the Furrial Field located in Monagas State in Eastern Venezuela (Fig. 1).
The furrial structure is an overpressured asymmetric anticline containing over 4364 × 106 B [634 × 106 m3] of medium oil weight (29-24° API). Variable PVT properties, and variable asphalthene content, the presence of a tar mat surrounding the flanks of the structure, high initial pressure and temperature, high initial production rates and net sand thickness over 1000 feet are characteristics of this field considered as the most important in the Eastern Venezuela.
The reservoir characterization activities undertaken during the first six (6) years of production resulted in the identification of the production mechanisms and an estimate primary recovery. Pressure maintennance requirement were identified early and an action plan was defined to implement a water injection project. Reservoir studies indicate an incremental oil relovery by water flooding of about 1350 × 106B [215 × 106 m3].
Simulation Study of a Venezuelan Reservoir to Enhance Productivity
Authors: Miranda J. , Rodriguez L. 
Published: December 2007

ABSTRACT
This report presents the results of the simulation study of the NIP-101/R1 sand reservoir, NIPA-100 oil field, located in Eastern Venezuela. The objective of this study was to establish the optimum future exploitation strategy.
Originally the reservoir was undersaturated, containing 15-22 API crude at 3870 psi (26.7 MPD) and 240 F (113 C). The initial gas/oil ratio was 436 Scf/bbl (79.9 M3/M3).
A detailed geological model was constructed based on recent depositional environment concepts, using available core and log data. The study concluded that the NIP-101/R1 sand reservoir had a deltaic origin. It was divided in two different lenses in most of the reservoir, except around well NV-106, where both lenses coalesce. The top R1U lens and the bottom R1L lens are channel sands with local splays.
A satisfactory match of reservoir production and pressure history was achieved. A pressure performance history match was obtained by reducing total gas injected by 7.3% by adjusting the reservoir transmissibility.
A total of seven prediction cases were run to analize the sensivity of oil recovery as a funtion of various exploitation schemes, including horizontal wells.
The results indicated that by injecting 14 MMSCFD (.40 MMCMD) of gas, relocating the injection wells, and drilling seven additional new vertical wells, the oil recovery will be improved in 4.67 MMSTB (0.75 MMCM).
Safety Systems for Production Platforms
Authors: Lozano P. , Sánchez D. 
Published: December 2007

ABSTRACT
During 50 years in operation of the petroleum industry in the western part of the country, the surface of Lake Maracaibo has become congested with approximately 10,000 structures, among them well platforms, flow stations, pumping maniflod, production and gas lift manifolds, water injection and gas compression plants, etc. this progressive increase by the number of installations has continuously limited the moving of floating units in the lake as well as increasing the risks of contamination due to the high probability of leakage occurrence in the 21,000 kms. of pipe line resting on the bottom of the lake.
Because of this situation, the LAGOVEN Western Division initiated in 1988 the perforation by groups, drilling 17 wells in two platforms to inject water into an oil bed. In 1990 the first platform was built with 10 oil producing wells, and to obtain a reliable and secure operation of the facility, during the activities of repairing and /or servicing the wells, a security system was designed which included an amergency shutdown.
In this article, we will describe the safety system mentioned above, their specifications, functions and the benefits obtainable when we have this system in operation.
A Method to define Gas Condensate from Initial Production Data, Eastern Venezuela
Authors: Cova J. , Essenfeld M. , Silva L. , Rondón C. 
Published: December 2007

Abstract
Using as data base a group of correlations generated from Eastern Venezuela PVT Laboratory experiments, a group of "minimum limiting conditions" based on simple field production measurements are proposed which, when met simultaneously, guarantee that the produced fluid stream is a gas condensate at reservoir conditions. It was also concluded that for each of the selected production parameters there is a "Transition Zone" in which the production stream can be a volatile oil or a gas condensate at reservoir conditions. It is concluded that the proposed method to define the existance of such gas condensates is very important for Eastern Venezuela since it expands the typical ranges that several authors have indicated to clasify the produced fluids as gas condensates at reservoir conditions.
The Application of Geochemical Kinetic Modelling to Petroleum Engineering: the Prediction of Hydrocarbon Composition
Authors: Bagge M. 
Published: December 2007

Abstract
Significant advances have been made in the description of oil composition and cracking under different temperature regimes. This paper describes how geochemical methods, previously applied to oil exploration, can be used in petroleum engineering studies to predict oil composition and phase behaviour when thermal processes are applied to enhanced oil recovery. Laboratory and field data from both geochemical and petroleum engineering sources are, reviewed, and then applied in a series of models generated using geochemical software.
The composition of oil and its products on cracking are very sensitive to temperature, but their prediction must be treated as a time-temperature process using chemical kinetics. Experimental evidence shows that a distribution of activation energies can be assigned to each oil to describe its composition at a range of temperatures. Kinetic models show that compositional changes and cracking occur at different rates at the high temperatures used in laboratory studies to the temperatures normally encountered in the subsurface. Furthermore, oils of different compositions, for example the heavy degraded oils common in Venezuela, can have different breakdown characteristics to paraffinic oils.
Conclusions from this work have direct applications to reservoir simulation for a complete compositional fluid description. The models could be used to describe oil composition in fields where high subsurface temperatures are encountered, and would aid the planning of enhanced recovery programmes using thermal recovery processes to predict production characteristics. Where simulators are used hydrocarbon compositions are predicted using a set of flow equations that model convective and conductive mass and heat transfer in the reservoir.
Application of this knowledge base greatly enhances our understanding of fluid behaviour in reservoirs. The ability to predict oil composition under different thermal regimes will play a major role in assessing exploration risk associated with drilling deep prospects, but also improves our ability to predict production characteristics.
A Review Of The Developments In Oil Well Drilling Techniques In The Agreement Area, 1962-1967
Authors: Parsai K. 
Published: December 2007

Introduction
The Iranian Oil Exploration and Producing Company is now making considerably more footage at less cost in the Agreement Area than it was making five years ago. The estimated exploration Cost per foot for 1967 is only 47% of the actual cost in 1962 and the estimated development cost per foot 72% of that of 1962.It is the aim of this paper to indicate the factors responsible for such dramatic progress over the past five years.

Discussion
The reduction in drilling cost per foot of 53% in the exploration field and 28% in the development wells over the 5-year period 1962 - 1967 in the Agreement Area is dually significant in that we not only drill at a relatively lower cost per foot now than in 1962, but because of the generally high cost of drilling in the Agreement Area, this relatively lower cost implies a significant saving in the total operating costs of the Company. The overall progress achieved in Drilling in South Iran is attributable to improvements brought about in individual phases of operations, each of which is discussed a briefly in the following:

1. Drilling Hydraulics
A major contributor to the improved rate of penetration in the south Iranian Fields was the introduction of jet bitdrilling about 1960.
The early jet bit, however, did not achieve the degree of merit it deserved as we did not have pumps with the required pressure ratings for ultimate efficiency in jet bit drilling.
Visual Investigation of Imbibition Processes
Authors: Hayashi J. A. , Rosales C. Pérez 
Published: December 2007

ABSTRACT
A new technique for making visual observations of water imbibition processes in porous media saturated with oil is described. This technique uses a two-dimensional cell built with two ground glass plates set in contact one against the other. A porous space between the two plates is formed, where the microscopic pores have a random distribution similar to that of a natural rock. Using an oil with the same refraction index as that of the glass, it is possible to observe in detail the spontaneous penetration of the water by imbibition. Based on experimental results, a theoretical model is proposed for explaining imbibition processes.
Use of Reeled Tubing in Gas Lift Completion Systems
Authors: Bortolin L. , Johnson K. J. , Bechtold H. D. 
Published: December 2007

ABSTRACT
This paper will demonstrate the use of reeled (coiled) tubing applied to gas lift technology and will add another method to the growing list of service and production capabilities now facilitated by reeled tubing. By using reeled tubing to install conventional gas lift valves, production enhancement of many wells is possible without workovers or change of existing tubulars. This paper will discuss the design parameters, components and actual field results of using reeled tubing to install gas lift valves.
On Reversed Micelles, Supercritical Solutions, EOR and Petroleum Reservoirs
Authors: Carnahan N. F. , Quintero L. 
Published: December 2007

ABSTRACTGale (1987) reported the combined solvent power of supercritical fluids with the solvent power of micellar solutions which appears promising in connection with enhanced oil recovery. Likewise, recognition of the possible formation and destruction of reversed micelles by naturally-occurring amphiphilic substances, such as those associated with asphaltenes, may explain problems experienced in some EOR projects. Lipophilic supercritical components of reservoir fluids (e.g. light hydrocarbons and CO2) interact, in a controllable manner, with hydrophilic micellar complexes to achieve selective extraction of desirable components of crude oil. Fundamentals of supercritical fluids and of micellar systems are reviewed in terms of their mutual interaction and their potential applicability in EOR processes.
The Effects of Erosion Velocity on Filter-Cake Stability During Gravel Placement of Openhole Horizontal Gravel-Pack Completions
Authors: Johnson M. H. , Ashton J. P. , Nguyen Hang 
Published: December 2007

Abstract
This paper describes the data obtained from multiple rate flow tests intended to simulate the circulation of typical completion fluids across open hole intervals supported by particle filter cakes of graded salt and graded calcium carbonate. All flow rates, fluid losses and changes of permeability were recorded to determine changes in filter cake stability caused by the fluid flow.
Studies, Guidelines, and Field Results of Nonviscosified Completion Brine Gravel-Pack Carrier Fluids
Authors: Johnson M. H. , Montagna J. N. , Richard B. M. 
Published: December 2007

Abstract
The use of high viscosity gravel pack carrier fluids in gravel packing operations has been an accepted industry practice for more than 20 years. However, experimental results obtained using an acrylic gravel pack simulator indicated completion brines were superior gravel carrier fluids when compared to viscous polymer systems. The low viscosity brines exhibited complete annular packing with very tight grain to grain compaction. The low viscosity systems also provided good perforation filling without the degree of turbulence necessary for intermixing formation and gravel pack sands. Non-viscosified completion brines have been used to complete more than 100 zones with interval lengths of &lt; 10 ft (3.05 m) to 400 ft (121.92 m) and hole angles from vertical to 89 ° (1.55 rad) at depths in excess of 13,000 ft (3,962.4 m). The low viscosity brines have yielded excellent annular packs and exhibited superior perforation packing when compared to polymer carrier fluids. Simulator test results, gravel crushing and erosion tests, and a discussion of "Slurry Pack" versus non-viscosified carrier fluids are presented. Also, comparative field results between polymer fluids and low viscosity brines are also presented in conjunction with recommendations and procedures for gravel placement using non-viscosified completion brines.
Frac-Pack: An Innovative Stimulation and Sand Control Technique
Authors: Hainey B. W. , Troncoso J. C. 
Published: December 2007

Abstract
A frac-pack technique combines the stimulation advantages of a highly conductive hydraulic fracture with the sand control of a gravel pack to improve productivity in low to moderate permeability, unconsolidated formations. This paper presents the results of two offshore field tests in the Gulf of lexico which evaluate different fracturing fluids, unconventional proppant sizes and new gravel packing tools. Aspects of reservoir candidate selection, pre- and post-frac pressure testing, and production results are addressed. This paper examines the layout of equipment, fracture treatment design, and on-site fracture optimization through minifrac testing.
The first field test explores the use of platform mounted gravel pack tanks with batch mixed sand slurries in a linear hydroxypropyl guar (HPG) gel that is crosslinked with Borate on the fly. The second field test investigates the use of linear hydroxyethylcellulose (HEC) gel as a fracturing fluid with a conventional blender and gravity feed proppant silo on a stimulation boat moored along side the production platform. These field tests demonstrate a frac-pack technique can provide practical and cost effective fracture stimulation and sand control in the offshore environment.
Point Permeability Measurements Using a Liquid Minipermeameter to Study Formation Damage Mechanisms
Authors: Vassilellis G. D. , Graves R. M. , Crafton J. W. 
Published: December 2007

Abstract
An apparatus that enables spot measurements of permeability variations along a core measuring 2 inches in diameter and 5.5 inches in length was developed. The apparatus is based on liquid injection at the rock surface and is referred to as the "Liquid Minipermeameter" (LMP). During the LMP measurements, full saturation of the rock sample is ensured by using a saturation bath. LMP measurements are also compared against air minipermeameter measurements. During liquid injection using the LMP, flow patterns were studied through the injection of colored liquids.
Various formation damage mechanisms on consolidated rocks using conventional coreflooding apparatus have been studied in conjunction with LMP measurements. LMP measurements were conducted before and after the formation damage experiments. The present paper includes an interpretation of a complex formation damage mechanism involving precipitation of gelatinous iron hydroxide. In this case, spot permeability measurements provide valuable information on the extent of damage as it is shown from LMP spatial variations.
Advantages of the LMP measurements arise as the measurements are not destructive for the rock sample and the rock heterogeneity is not excluded from the interpretation of the formation damage experiments. Compared to air minipermeameter the LMP shows better repeatability while drying of the rocks is not necessary.