bluuebunny/crossref_metadata_2025_split huggingface dataset:
Diffusion of Advanced Stimulation Technology in the Petroleum Industry: A Case History
Authors: Wolhart S.L. , Hill D.G. , Smalley E.A. 
Published: December 2007

Abstract
In 1995, Gas Research Institute undertook an aggressive technology transfer program to deploy the results of over a decade of research in the area of hydraulic fracturing. The program was called the Advanced Stimulation Technology (AST) Deployment Program. The intent was to transfer advanced fracturing technology as widely as possible to the natural gas industry through programs with producers and service companies focused on education, training, demonstration and documentation. The goal was to disseminate the technology on a level such that, if beneficial, it would continue to be practiced beyond completion of the GRI program. AST incorporates a process of data collection, real-time analysis and onsite job optimization into the design, implementation and evaluation of hydraulic fracturing. Several of the critical concepts involved in this process include:real-time analysis,quality control,stress profiling androck mechanics.
Based on field results, AST can have a significant impact on well productivity and completion costs. Companies have documented fracturing cost savings of up to 50% and/or well performance improvements of up to 300%, depending on current practices and conditions. The average improvement is a 20% reduction in treatment cost and a 25% increase in production, although not necessarily on the same well at the same time. This paper focuses on the key components involved in new technology diffusion, technology transfer barriers and the strategy GRI used to overcome these barriers.

Introduction
Moving a technology or innovation from an idea to widespread acceptance is often very difficult. This process can be a lengthy one, and accelerating the time to market acceptance has been an area of intense study. Technology diffusion can be defined as the process by which an innovation is communicated through certain channels over time among the members of a social system. The rate of technology diffusion or dissemination is controlled by many factors which are defined by both the innovation and the user or adopter. The decision to adopt an innovation is based on the perception of the innovation by the adopter and can be characterized by five qualities:Relative advantage - how much better is the innovation than the idea it supersedesCompatibility - is it consistent with existing values, past experiences and needs of the potential adopterComplexity - how difficult is it to understand and useTrialability - can it be experimented with on a limited basis, andObservability - are the results of the innovation visible to others.
Research has shown these qualities to have the greatest influence on the rate of adoption. Innovations that are perceived by individuals as having greater relative advantage, compatibility, trialability, observability and less complexity are adopted more rapidly than other innovations.
P. 779^
State of the Industry in CO2 Floods
Authors: Grigg Reid B. , Schechter David S. 
Published: December 2007

Abstract
Every other year the Oil and Gas Journal presents a summary of worldwide enhanced or improved oil recovery (EOR or IOR) methods and current production.1 Other papers review EOR technologies and present U.S.A.ge, both in the US and worldwide.2,3 Our intent was not to duplicate this type of documentation but to review CO2 as a maturing EOR process and to assess what was going well in the field as well as what was not going well, to identify research opportunities, and to develop correlations between problems encountered and solutions developed. A survey was sent to a number of engineers responsible for day to day operations of CO2 floods. This paper reviews the response received concerning 25 projects. Represented in the responses are experiences from 25 fields by 19 different engineers employed by nine oil companies.
Analysis And Interpretation Of The Water-Oil Ratio In Waterfloods
Authors: Yortsos Yannis C. , Choi Youngmin , Yang Zhengming , Shah Piyush C. 
Published: December 2007

Abstract
An important problem in water control is the identification of the dominant reservoir or production controls (for example, channeling or water coning). Recently, Chan (1995) postulated that a log-log plot of the produced WOR vs. production time may be used to diagnose these factors. In this paper we provide analytical and numerical results for a variety of waterflood conditions to explore this possibility.
We show analytically that the late-time slope of the log-log plot can be related to the well pattern, the relative permeability characteristics, specifically the power-law exponent in the kro - Sw relationship or the reservoir heterogeneity. Analytical results are also provided for the behavior immediately following water breakthrough. In certain simple cases (mobility ratio equal to one, layered systems), analytical type curves can be derived. In the general case, we use numerical simulation to provide numerical type curves.
The results are summarized in terms of the various power-law scalings in different time regimes and by a catalogue of numerical type curves. They confirm the potential of WOR-time plots as diagnostic tools for reservoir analysis and characterization.

Introduction
An important problem in water control is the identification of dominant reservoir or production factors (for example, channeling or water coning) from produced water-oil data. Water production can be the result of a natural water-drive, edge- or bottom water-drive or a waterflood. Despite its relevance, however, the problem has received rather scant attention in the literature so far. Aspects of waterflooding under various conditions have been extensively described in the literature (e.g. see the SPE monographs of Craig, 1971, and Willhite, 1986). Limited, however, are studies on the dependence of WOR on production time. Ershaghi and Omoregie (1978) proposed the so-called X-plot, to interpret and extrapolate water-oil production. In this approach, a combination of the fractional flow function was found to vary linearly with time, in an appropriate semi-log plot. The X-plot method successfully matched various field data.
In a more recent study, Chan (1995) used numerical simulation to examine the sensitivity of the curve of produced WOR vs. production time on various reservoir and production factors. He conjectured that a log-log plot of this curve can be used to diagnose the origin of the water production, and specifically to determine whether it is due to channeling (heterogeneity) or to coning. An essential part of this conjecture is that a log-log plot of WOR vs. production time contains linear segments, the slopes of which are different in the cases of channeling or coning, hence they can be used for diagnostic purposes. No expressions for these slopes were postulated or derived, however. Chan's conjecture is presumed to have strong support from numerical simulations and field data.
P. 261^
Oil Composition Variation in a Large Deep Water Field
Authors: de Oliveira Pádua Kleber Galvão 
Published: December 2007

Abstract
A new computational model for the non-isothermal gravitational compositional equilibrium is developed and presented.
The mathematical formulation is based on the works of Bedrikovetsky (gravity and temperature using irreversible thermodynamics) and Whitson (algorithm). The computational model is validated on published data and previous simplified models.
An application case is presented for a reservoir in a large deep water field in Brazil. The magnitude of the calculated oil composition variations is sufficient to explain most observed data. The results suggest that the reservoir is partially connected and that the temperature effect can be as important as the gravity effect on the oil composition variation. The changes are significant and the methodology applied is an example of the application of thermodynamic data to the evaluation of reservoir connectivity and fluid properties distribution under the conditions approaching those encountered in natural reservoirs.

Introduction
Compositional variations along the hydrocarbon column are observed in many reservoirs around the world.
They may affect reservoir/fluid characteristics considerably, such as viscosity, total hydrocarbon volume in place and the development of miscibility, leading to different field development strategies.
These variations are caused by many factors, such as gravity, temperature gradient, rock heterogeneity, and hydrocarbon genesis and accumulation processes.
In the cases where thermodynamic associated factors are dominant, the existent gravitational compositional equilibrium (GCE) models, which do not properly account for the temperature gradient effect, allow the explanation of most observed variations. However, it is noted that in some cases, the thermal effect could have the same order of magnitude as the gravity effect.
In this paper, a non-isothermal compositional gravitational model is developed and presented. The model is validated and applied to some fields in Brazil, among them a large deep water field.
High-resolution stratigraphy and geometry of lacustrine turbiditic deposits in a rift succession - Alagoas Basin, Brazil
Authors: Arienti L. M. , de Azambuja Filho N. C. , Backheuser Y. 
Published: December 2007

Abstract
This work deals with the Aptian rift lacustrine succession of Maceió Formation, Alagoas Basin, northeastern Brazil, comparing outcrop information with data from 16 wells of Tabuleiro dos Martins Oil Field (average distance between wells of 200m and 718 meters of cores). Detailed facies and facies associations descriptions were performed, characterizing three main types of deposits: channel/overbank turbidites (outcrops), lobes/interlobes and lacustrine deposits (wells). High-resolution stratigraphy was applied to identify the main stratigraphic sequences and to determine their lateral and vertical continuity. The succession was divided into three 4th order sequences: Alpha, Beta and Gamma. The Alpha Sequence (180 m) was divided into six 5th order sequences, the Beta Sequence (150 m) into four 5th order sequences and the Gamma Sequence (400m) into eight 5th order sequences. In cored wells, 5th order sequences were further subdivided into 6th order sequences.
Isolitic maps of 5thorder sequences were made to understand the distribution of the sandstones in the oil field (subsurface data) and a tridimensional model was constructed using the program Stratigraphic Geocellular Modelling (Landmark) to visualize the external geometry and the relationship between the sequences.
The general geometry and lateral continuity of channel and lobe deposits were compared and the internal heterogeneities, such as shale beds, were mapped to better define the geometry of sand bodies.
Development of a Dual Crosslinker Fracturing Fluid System
Authors: Yaritz Joseph , Stegent Neil , Bailey Tom , Fritcher Eddie 
Published: December 2007

Abstract
Studies of the production histories of wells in the Cotton Valley (CV) region of east Texas led companies to recognize the potential value of optimizing fracture design in this area. As a result, chemists developed a dual crosslink fluid (DCF) system that performs best at high temperatures and moderately high pH levels and uses guar as the gelling agent. The new system has enhanced viscosity and an adjustable crosslink rate.
Because the CV sand formation is a "tight gas sand" region, drilling companies have focused on reducing fracturing costs without hindering well production. The use of the DCF system has resulted in fewer screenouts than Zr-guar systems in the CV formation, and it is a more economical alternative to fracturing fluids that use guar derivatives, such as hydroxypropyl guar (HPG) and carboxymethyl hydroxypropyl guar (CMHPG) as the polymer.
By using a moderately high pH and combining the borate crosslinker with a zirconium (Zr) crosslinker, operators have been more successful at placing proppant in a fracture. The performance of previously used Zr-guar-based fluid systems was often unpredictable at the higher temperatures. The DCF crosslinkers have a synergistic relationship; the viscosity of the combined system is higher than the sum of the separate systems' viscosities. The new system improved operational efficiency to greater than 96% in over 85 treatments last year in the CV region. Gas production from wells treated with DCF is similar to that of the higher-priced CMHPG and HPG fluid systems that use zirconium as the crosslinker.

Description of the Region
Gas production from the Cotton Valley (CV) formation, which includes 14 fields in east Texas, has grown steadily since 1978. Divided into three major areas - Carthage, Oakhill, and Waskom - the depositional system is a transgressive-regressive marine sequence bounded by the Bossier shale below and the Travis Peak formation above (Fig. 1, Page 6). The formation sediments were deposited in a dominantly progradational sequence of shallow marine and fluvial-deltaic environments. The CV formation is Upper Jurassic and is about 1,200 to 1,500-ft thick at depths ranging from 8,000 to 11,000 ft. The area is divided into two major intervals: the upper Cotton Valley (UCV) and the Taylor Sand. In 1980, the low-permeability CV sandstones were classified as "tight gas sands" by the Federal Energy Regulatory Commission (FERC). Permeability of the productive CV sands is typically between 0.01 and 1.0 md. with porosities up to 15% but generally in the 6 to 8% range. Numerous depositional analogs to the CV system exist worldwide.
Integrated Study of Shale Stability in Deepwater, Brazil
Authors: Santos H. , Rego L. F. B. , da Fontoura S. A. B. 
Published: December 2007

Abstract
The development of the huge hydrocarbon reserves located in the deepwater portion of the Campos Basin requires hundreds of wells. In the early exploitation stage, wellbore stability problems were faced in some of the wells, leading to significant losses. In the second Deepwater Technological Program launched by Petrobras in 1992, called PROCAP 2000, one of the projects (out of 11) contemplated the study of the shale instabilities observed. This paper describes this project, the motivations to create it, and the steps to define the topics to be studied. It also describes how the team was chosen, integrating people from the different areas in the company, and from universities and service companies. The paper presents the most important results and how they are being implemented in the field in order to optimize the future wells. Finally, a field case of an extended-reach well drilled in the Campos Basin is discussed, proving the correctness of the project's conclusions.

Introduction
With the discoveries of giant oil fields in the deepwater section of the Campos Basin in the mid 80's, Petrobras was forced to develop technology not available at that time to produce those reserves. The first deepwater technological program, PROCAP 1, was successfully conducted and concluded in the beginning of the 90's. With oil reserves extending to water depths beyond 2000 m, a second program was initiated in 1992. From the experience gained in the previous program, and also from the development of some fields, 11 projects were defined. The main restrictions and difficulties were put together in these projects in all areas from drilling to production facilities.
The development of the hydrocarbon reserves requires the drilling of hundreds of wells. The original idea was to use inclined wells - extended reach and/or horizontal wells - in order to reduce the overall cost of the development stage. The increased complexity of the wells and the geological challenge imposed by the formations located in deepwater, required careful planning of the exploitation scheme, not only to reduce the risks, but also to guarantee economical success. Due to bad experiences on some vertical wells, the decision to create a project focusing on the stability and planning of the wells was strategic.
The managerial aspects of the project are emphasized in this paper. The innovative approach of conducting an integrated project, considering all the aspects that can contribute to the instabilities, turned out to be the most important factor for the success of the project. Due to its multidisciplinary characteristic, involvement of different specialities was a must, creating a challenge to the managers. The most important results are presented here, including the strategies to disseminate them among the operational people. Implementation of the new technology developed is actually the most important item of any research project and it was emphasized at all times during the course of the project.
Reservoir Studies in Fluvial Deposits: From Outcrops to Stochastic Characterization and Flow Simulation
Authors: Ballin P. R. , Faria R. T. , Becker M. R. , Carrasco B. N. , Teixeira P. W. 
Published: December 2007

Abstract
Traditional models for describing complex reservoir geology are not able to adequately represent the heterogeneities and, therefore, to capture most of the aspects that impact on fluid displacement. Stochastic simulations can describe the complex geological architecture, the spacial facies distributions and the significant internal variations of reservoir properties. Although, these simulated scenarios are conditioned to available data - well data - a large portion of the model still has a significant amount of uncertainty - interwell areas. To reduce this problem, the study of analog outcrops gathers a great amount of information that can be taken into account on the stochastic models, decreasing the uncertainty in the interwell scale.
The focus of this paper is on quantification, modeling and stochastic simulation of a highly heterogeneous fluvial reservoir considering the fine scale information from outcrops. Two outcrops and an oil field in the sandy braided fluvial facies of the Cretaceous Açu Formation, Potiguar Basin, NE Brazil, were used in this study. Roadcut outcrops description and the analysis of data from shallow drilling wells and from a high-resolution seismic line allowed the modeling of the surface reservoir analog based on the lithological variability at megascale (genetic units) and macroscale (lithofacies). Outcrop-based geologic model supported the geostatistical description used to stochastic simulate the petrophysical variability in the subsurface reservoir. Flow simulation studies of the reservoir were held considering the output of the geostatistical modeling and an integrated iterative approach was required.
Quick Look Method Of Log Interpretation Using Magnetic Resonance Porosity And Dielectric Porosity
Authors: Alguero A. , Glorioso J.C. , Mallaviabarrena M.A. 
Published: December 2007

Abstract
In the never ending search to reduce drilling cost the ability to reduce the time spent in analyzing well logs and making well completion decisions in a timely fashion is very important. The ability to make Quick Look wellsite decisions has proven elusive in the Neuquen basin due to the complex lithology encountered in the basin.
New generation logging tools now exist that make dependence on Archie's equations and all the variable parameters that are needed by them not a requirement in reaching sound decisions in the early step of new well completion. Through the comparison of the mineralogy free porosity provided by Nuclear Magnetic Resonance tools and the highly water filled dependent porosity available from the Dielectric tools a method has been found to make a quick look well site qualitative interpretation.
In combination with Rw and Rwa overlay methods we are able to confidently make decisions much more quickly and save considerable rig time.
The objective of this paper is to demonstrate a visual comparison of the two porosity indicators and their use to highlight probable productive zones. A Rw and Rwa overlap method is also demonstrated in confirmation of the method.

Introduction
New technology logging tools for the formation evaluation of exploratory wells, such as Nuclear Magnetic Resonance and Multiple-channel induction, has created a need to make their interpretation easily available. Western Atlas and the West Region Exploration Department of YPF SA have designed a new log presentation by combining different logs and adding "Quick-Look" processing. This helps in identifying hydrocarbons zones and facilitates the decision making process at the wellsite The reward is doubled:
- save in well completion costs and
- reduce the risk of bypassing productive zones.
Permeability from Well Logs of an Eolian and Fluvial Formation. Entre Lomas Block, Neuquen Basin, Argentina
Authors: Benito J.I. , Montagna A.O. , Wouterlood C.J. 
Published: December 2007

Abstract
Accurate permeability values, required in reservoir characterization, can be derived from logs using adequate petrophysical constants with their cut-off for different lithologies and environments, specially in those fields where good relationship between porosity and permeability exists. This methodology has been successfully applied in Tordillo Formation in Entre Lomas Block, in the ENE of the Neuquen Basin, Argentina.
Tordillo Formation, of 150 m thick section, is composed of sandstone and conglomerate units interbedded with siltstones layers deposited under braided fluvial and eolian environments. Taking advantage of the logs that most of the wells at any field have, many authors, mentioned in Reference 1, have given various techniques to estimate permeability. In the majority of the cases, the evaluations show erratics behaviours.
To improve the quality of the results, core data (capillary pressures, formation factor, porosity, etc.) have been used to determine the irreducible water saturation and the different petrophysical constants in order to calibrate the permeability equation. This adjusted expression yields results which have good correlation degree with those permeabilities derived from direct and indirect measurements as core data and well test analysis.
Later, numerical simulation studies have confirmed the validity of the described method.

Introduction
Study Area. Entre Lomas Block is located at the northeast of the Neuquen Basin. Oil was discovered in 1960. The Block, with an extension of 742.5 Km2, is divided by the Neuquen and Rio Negro interprovince border (Figure 1).
The stratigraphic column (Figure 2), present in Entre Lomas Block, shows the three main productive Formations: Punta Rosada (Aalenian-Bajocian), Tordillo (Kimmeridgian), the most prolific, and Quintuco-Vaca Muerta (Tithonian-Valanginian). Tordillo Formation appears productive in two main structures, Charco Bayo (CB) and Piedras Blancas (PB). They are under exploitation since the late 60's. A secondary recovery project that started in 1975 was performed in several stages. The original pattern was inverted seven spot, but later a half of those patterns have been changed into a staggered line drive system.
Both structures are not completely developed neither close to the water contact nor inside the field. The future locations should be chosen carefully due to the risk of finding a thin pay zone or hitting a secondary water bank.
Up to day almost 330 wells of the CB and PB structures have been drilled. Almost 270 were located with a well spacing of 88 acres. The rest of the wells can be defined as interspaced. Currently 205 are still on production, 80 are injectors.
By December 1996, the oil production rate of Tordillo Formation was 1,180 m3/d and the cumulative produced volume was 17,234 Mm3.