bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calibrating Permeability Heterogeneity at the Core Scale to Static and Dynamic Data
Authors: Soltani A. , Le Ravalec-Dupin M. , Fourar M. 
Published: September 2008

Abstract
Special core analysis techniques are often based on the assumption of uniform petrophysical properties of core samples. This assumption is obviously erroneous for heterogeneous core samples. This paper presents an integrated approach for characterizing permeability heterogeneity at the core level. The method combines the results of laboratory core flooding with already developed field scale history matching techniques to identify a 3D heterogeneous permeability field at the core scale. We focus on core samples with local heterogeneities. Their 3D porosity maps are preliminary obtained using conventional tomography techniques. Production data are measured when performing a viscous miscible displacement experiment: a high viscosity glycerin displaces a low viscosity brine at a constant flow rate. Concentration maps are collected at successive times during displacement using a medical CT device. A 1D permeability profile can be determined from the variations in the slope of the pressure signal against front location inside core samples. The 3D permeability fields are modelled using a relationship such as log(k(x)) = Aϕ(x) + b(x) where A is a constant and b(x)is a realization of a random function characterized by a mean, a variance and a variogram. We developed an assisted history-matching process, which takes advantage of all the available static and dynamic data to model permeability heterogeneity inside core samples. A first guess is initially generated honoring the measured Δp(t) variations along the flow axis. This first guess is subsequently modified until the mismatch between dynamic data and fluid flow simulated answers is minimized. To do so, we use a gradual deformation based optimization method, which allows us to vary any given distribution from one or a few deformation parameter(s) while preserving the overall spatial variability. The proposed method is fast and non-destructive. The final 3D permeability map honors the measured dynamic data and respects the spatial variability of the collected static data.
The Contradiction in the Lower Tertiary Deepwater GoM
Authors: Wiltgen Nick A. 
Published: September 2008

Abstract
Exploration in the Gulf has progressively moved farther and farther offshore. Initially oil companies concentrated on the shelf and then moved into the deep water and the Miocene trend. The Miocene is a well established trend with a considerable amount of producing acreage. With the acquisition and processing of data farther offshore, attention has switched to a new trend in the Lower Tertiary. The Lower Tertiary sits beneath the Miocene and is older.
The Tertiary time period includes Pliocene, Miocene, Eocene and Paleocene. We tend to lump everything below the Miocene into what we call the Lower Tertiary because our Wilcox sands are Paleocene and Eocene in age. Most of the cumulative GOM production has been Miocene in age.
This is an emerging play in the deepwater Gulf of Mexico, to date there have been 12 announced discoveries out of 19 wells drilled (Figure 1). This trend data is only for Alaminos Canyon, Keathley Canyon and Walker Ridge. There are additional penetrations along trend to the northeast.
There is a contradiction between traditional interpretation and NMR data in the Lower Tertiary. An NMR log (CMR) was run with the aim of identifying the best reservoir intervals of Porosity, Swir, and Permeability. The NMR log has many responses depending on the borehole fluid, free fluid and viscosity.
These results will be discussed.
Oil bearing interval with Swir higher than Sw CMR porosity undercalled in oil-bearing interval Little free fluid in oil-bearing interval Calibration of Klog permeability to core
Traditional logs indicate the presence and quantity of oil, but provide no information on its quality. NMR is sensitive to oil viscosity. NMR can be misleading in the presence of viscous oil as the oil signal can overlie the bound fluid volumes, resulting in the incorrect evaluation of the reservoir in an oil base mud system. The NMR must be used with caution in an oil base mud system (OBM).
Successful Deployment of Innovative Completion Technology Designed for Multi-Stage Fracturing Treatments in Horizontal Producers Achieved Significant Rate Increase in Saudi Arabia
Authors: Solares J. R. , Giraldo C.A. Franco , Al-Marri H. , Al-Hussain H. , Abualhamayel N. , Ramanathan Venkateshwaran , Ishteiwy O. A. , Johnson Bryan 
Published: September 2008

Abstract
One of the key strategies in Saudi Aramco's optimum gas development project includes drilling single and multilateral horizontal wells designed to achieve maximum reservoir contact to maximize productivity. This strategy has proven very successful over the past few years as the majority of horizontal gas producers have yielded excellent results, with open-hole completions in particular. Consequently, most of the planned future wells will be drilled as open-hole horizontal completions.
However, due to the complex nature of the Khuff reservoir some wells have experienced complications during the drilling phase, encountering unexpected reservoir challenges, and hence not meeting production targets. These wells require stimulation to regain their productivity, but the available choices to achieve effective stimulation in horizontal open-hole completions have traditionally been limited at best. Previous stimulation attempts with coiled tubing have yielded modest improvements mainly due to the difficulty in accessing the long, deep, and high pressure/temperature zones requiring treatment. Bullheading treatments at high injection rates have also yielded similar modest well productivity enhancement. Consequently, Saudi Aramco field tested an innovative new completion technology that provided the ability to selectively fracture stimulate multiple zones along the horizontal section, yielding excellent and highly promising results which compared favorably with the performance of non-stimulated offset wells.
It is well known in the industry that fracture stimulating horizontal open-hole completions with conventional methods is a challenging endeavor, and that often-time results are disappointing. The new completion technology overcomes challenges associated with horizontal well fracturing, and provided a tool to achieve effective stimulation. Through this technology multiple mechanical isolation points are created in the wellbore, using specially designed multiple open-hole packers, and then selected zones of varying lengths can be individually treated in accordance with reservoir characteristics and production targets.
This paper details the planning and design processes leading to the implementation of the technology, the experience and lessons learned during deployment of the completion, and the stimulation treatment execution and post-stimulation results. Lessons learned from this successful experience are discussed as a way to enhance the benefits from this promising technology.
Predicting Sorption-Induced Strain and Permeability Increase with Depletion for CBM Reservoirs
Authors: Clarkson C. R. , Pan Z. , Palmer I. , Harpalani S. 
Published: September 2008

Abstract
It is well known that absolute permeability changes occur in coalbed methane (CBM) reservoirs during primary depletion or enhanced recovery/CO2 sequestration operations. Sorption-induced strain in CBM reservoirs, also known as matrix-shrinkage or -swelling, may dominate permeability changes at low pressures, as is the case for CBM wells undergoing primary depletion in the Fruitland Coal fairway of the San Juan Basin.
Several analytical models have been developed to predict changes in coal permeability as a function of stress and sorption. Most models, however, utilize an empirical method for estimating sorption-induced strain. Recently, a theoretical model for sorption-induced strain was developed and applied to single-component adsorption/strain experimental data. The new model was developed from basic thermodynamic principles and is more predictive than the empirically-based approaches. In this paper, the theoretical model is expanded to incorporate multi-component adsorption models that are more rigorous, and sometimes more accurate, than the commonly-applied Extended Langmuir equation. This improves predictions of multi-component gas sorption-induced strain, as demonstrated by comparison to experimental data. The new sorption-induced strain model is then used to calculate the sorption-strain component of the popular Palmer and Mansoori equation, which in turn can be used to model permeability changes during both primary (single or multi-component gas) and enhanced recovery operations. Finally, the coupled sorption-strain/permeability model, incorporated into an analytical simulator, is used to predict and match permeability growth in a producing CBM well in the Fruitland Coal fairway, which has a binary (CH4+CO2) sorbed/produced gas composition.
Matches to field-derived permeability growth using the new model are accurate but non-unique, due to lack of available data, particularly rock mechanical properties. Given the availability of rock mechanics and adsorption isotherm data, the rigorous thermodynamic basis of the new model should allow for more accurate predictions of coalbed permeability changes, but further testing is required.
Characteristic Research of Air Injected Hydrocyclonic Separators
Authors: Jiang Minghu , Zhao Lixin , Sun Fuqing , Tan Rong , Song Hua 
Published: September 2008

Abstract
An air-injected de-oil hydrocyclone was developed, which has a dual function of hydrocyclonic separation and floatation separation so as to have better separation efficiency by overcoming the disadvantages of normal used hydrocyclone and floatation facility to a great extent. It has a similar structure with normal hydrocyclones, but an outer shell was added on vortex cavity, large cone section, or fine cone section, which was made by a kind of micro-pore material. Basic separation principle, prototype structure, experimental process and facilities are introduced. The effect of geometric parameters, including vortex finder diameter and length, micro-pore diameter, and different operating conditions, such as flowrate, split ratio, gas-liquid ratio, and air-injecting position, were studied. Laboratory experiments were carried out first to provide basis for field tests. The field research indicates that, for around 1000 mg/l polymer-flooding oily-water, the optimum flowrate is 4.20 m3/h for the testing prototype, the split ratio should be 30%; gas-liquid ratio 0.45. It also shows that 20-40 μm micro-pore materials are optimum diameter for hydrocyclonic separation enhancement. Research indicates that it has satisfied separation effect, which is feasible for emulsified oil treatment. This kind of hydrocyclone will have better application prospect in petrochemical, environmental field, especially for offshore application.
Fluid Characterization for Miscible Floods
Authors: Yuan Hua , Chopra Anil , Marwah Vineet , Stalkup Fred 
Published: September 2008

AbstractThe compositional simulation of a miscible gas injection process depends on an equation of state (EOS) model. An EOS model should not only predict traditional black oil PVT experiments for reservoir fluids but also experiments that give gas-oil compositional information, such as swelling tests, multi-contact tests, and slim-tube MMP. The two most common methods used to estimate MMP with an EOS model are traditional slim-tube simulation and, more recently, the analytical tie-line method. In most cases, the MMP computed from a slim tube simulation agrees well with the analytical tie-line method, but on some occasions, the MMP computed from the analytical method differs significantly from the value derived from slim-tube simulation. Additionally, for some gas floods, slim-tube simulation seems to identify an apparent MMP, but the analytical tieline method fails to give a solution. In this paper, we identify the reason behind these apparent discrepancies: physical dispersion and phase behavior. Thereafter, we propose a reservoir fluid characterization procedure for miscible gas floods that more accurately represents the interaction of flow and phase behavior. We demonstrate this approach for two different gas floods.
Rapid Country Entry Risk Screening Using Objective Relevance-Weighted Model for Transnational Petroleum Initiatives
Authors: Rajan Surya 
Published: September 2008

Abstract
In OECD Europe, oil consumption increased from 13.7 MMbbl/d in 1990 to 15.5 MMbbl/d in 2005, net increase 1.8 MMbbl/d. Oil consumption is expected to rise only 0.1 MMbbl/d in OECD Europe over the next 15 years. In Russia and FSU countries, though, oil consumption is expected to dramatically increase in next 15 years after years of low consumption levels. Moreover, developing Asia and Middle East is expected to reshape future oil markets. As Rate of Reserve Replacement continues to be challenged, International Oil Companies (IOCs) face competition from other IOCs as well as from entrepreneurial national oil companies (NOCs) aggressively looking to develop assets domestically and overseas. A disproportionately large fraction of reserves are controlled by a few NOCs. Downstream resources are similarly pursued by NOCs and IOCs alike.
Rapid, objective risk assessment of potential countries or regions targeted for petroleum investments has become an increasingly essential part of business development in an equally dynamic global market. Though a critical decision point for transnational ventures, Country Entry Risk Screening remains time consuming, complex, often subjective, and generally provides no basis for objective comparison between candidate locations.
Application of the Rajan-Vikas model1 enables apples-to-apples comparison between shortlisted countries or regions. Applicable to IOCs, NOCs, or Service Companies (SCs) alike, the model uses scores on a consistent relevance-weighted risk factors matrix to perform simplified objective assessment of a potential country or region under consideration. Screening of candidate locations prior to actual project due diligence is greatly expedited. Model application produces reusable artifacts for quick future reference or input for later detailed project risk management.
Drillstem Testing For High Pressure Deepwater Wells: A Noncemented Floating Tieback Liner Technique
Authors: Hussein Sameh , Scoular Tom , Luo Yuejin 
Published: September 2008

Abstract
Current and future offshore exploration activity is penetrating to deeper reservoirs, driving the need for increased drillstem testing (DST) for high pressure and high temperature wells. Typically, liners are tied back to the surface to achieve reliable wellbore integrity and flow. In the past, these tiebacks require expensive cementing operations which also limit future wellbore re-entry options.
An innovative non-cemented floating liner tieback with reliable floating seals can improve the entire DST process by eliminating the cost and risk of cementing operations. In addition, the operator is able to retrieve the casing tieback and have the option to use the same well for appraisal or development phases.
The paper discusses the floating tieback system and details a case history on a high pressure well in which the operator completed the DST operation safely and met all well objectives. Discussion of system reliability includes casing design and modeling by both operator and suppliers, plan changes based upon pressure data obtained during the drilling phase, detailed operational procedure in a deepwater environment, successful tieback retrieval and future operations.
Field Applications of Capacitance-Resistive Models in Waterfloods
Authors: Sayarpour M. , Kabir C. S. , Lake L. W. 
Published: September 2008

Abstract
Application of fast, simple and yet powerful analytic tools, capacitance-resistive models (CRMs), are demonstrated with four field examples. Most waterfloods lend themselves to this treatment. This spreadsheet-based tool is ideally suited for engineers who manage daily flood performance. We envision CRM's application to precede any detailed full-field numerical modeling.
We have selected field case studies in a way to demonstrate CRMs capabilities in different settings: a tank representation of a field, its ability to determine connectivity between the producers and injectors, and understanding flood efficiencies for the entire or a portion of a field.
Significant insights about the flood performance over a short period can be gained by estimating fractions of injected fluid being directed from an injector to various producers and the time taken for an injection signal to reach a producer. Injector-to-producer connectivity may be inferred directly during the course of error minimization. Because the method circumvents geologic modeling and saturation matching, it lends itself to frequent usage without intervention of expert modelers.
Utilizing 4D Microgravity To Monitor Water Encroachment
Authors: Alshakhs Mohammed J. , Riis Erling , Westerman Robin , Lyngra Stig , Al-Otaibi Uthman F. 
Published: September 2008

Abstract
The common wisdom is that gravity methods have limited application in the oil industry although they have long been available. The main use of gravity has been for exploration purposes. 4D microgravity monitoring is another new promising gravity application to monitor changes of fluid contacts. Some successful 4D monitoring surveys have been conducted in the industry revealing that this technique is a proven technology in monitoring of gas-water contacts.
This paper studies the ability of microgravity to capture movement of the injected water in a giant carbonate field. The oil-water case is more difficult due to the significantly lower density contrast as compared to the gas-water case. Monitoring water floodfront in the field is a key factor in applying successful reservoir management practices to maximize recovery and prolong the field life. The monitoring of inter-well fluids would characterize any pre-mature water breakthrough to allow planning and design of appropriate remedial well interventions. The current applied monitoring tools such as carbon-oxygen and resistivity logs can only detect fluids near to the wellbore due to their shallow radius of investigation. For the study field, 4D seismic cannot be used for fluid movement detection due to issues related to formation acoustics impedance and data quality.
The study has shown that surface microgravity monitoring could successfully detect the inter-well fluid changes due to water injection with a high precision tool (0.01 microgal). It also shows that microgravity monitoring can capture water bodies located hundreds of meters away from the location of the 4D measurement.
Interaction Between Intelligent Well Applications and Reservoir Management—A Comprehensive Thermal Modeling Technology for IWS Well
Authors: Sun Kai , Constantine Jessse , Coull Craig 
Published: September 2008

Abstract
Can we predict how Intelligent Well Systems (IWS) and equipment operate in various wellbore conditions to meet production enhancement targets? This paper presents a developed modeling technique and demonstrates how this technology can guide IWS equipment operations/design to meet production enhancement targets for a deepwater multiple-zone IWS water injection well.
Since IWS solutions typically address multi-zone (commingled) production or injection wells, it is important to develop a well deliverability model. Within this model, several key features include; a.) Multi-zone inflow/delivery including the unique zonal reservoir and fluid properties, b.) Multiple production/injection flowpaths to accommodate tubing flow for one zone and annulus/tubing flow for other zones, c.) Simulation of the effect upon wellbore pressure and flow distribution due to geometry changes within a completion string (i.e., gravel pack system, flow control equipment, etc), d.) Simulation of the fluid temperature profile and the effect on pressure and flow profile. Industry-available nodal analysis products have historically shown limitations in these types of applications. To fill this purpose, a comprehensive thermal model and an integrated analysis tool have been developed.
The modeling results provide an insight into how choking of downhole valves and tubing wellhead pressure impacts the injection fluid flow distribution. For any IWS operation scenario, the flow distributions, wellbore pressure profile, fluid temperature profile, and the fluid velocity profile can be predicted. This assists in determining any erosion concerns on equipment, flowing differential pressures through the valves and expected loads from temperature changes. This flexibility is the added value, where operators can choose the operational configuration to achieve their production objectives. The model results have been compared with several third party softwares and real case production data. Analysis and comments of the comparison are provided.
The Importance of Deposition Measurements in the Simulation and Design of Subsea Pipelines
Authors: Akbarzadeh Kamran , Ratulowski John , Davies Tara 
Published: September 2008

Abstract
Conventional practices for estimating the amount of deposited organic solids in pipelines are usually based on either the assumption of total deposit equal to total precipitate or the predictions with simulation packages using limited lab-scale deposition data with stock tank oil under laminar flow in small flow loops. Such practices, however, often lead to either overdesign or underdesign of pipelines and surface facilities. For optimized designs, more representative lab-scale deposition measurements which lead to more representative simulations are therefore required. In this work, a high pressure deposition cell which operates based on the Taylor-Couette (TC) flow principals and can mimick pipeline operating conditions is used to generate more representative deposition data with live reservoir fluids under turbulent flow conditions. The analogy between TC flow and pipe flow is explained and a scalability flow chart for linking the lab scale deposition data from TC configuration to pipe configuration is presented. Through a case study, the scaled deposition data is then used to tune a wax deposition model in the OLGA®5 simulation package. Next, the tuned model is applied to predict wax deposition under actual production and transportation conditions. The importance of tuning the deposition models with live fluid data under turbulent flow conditions is also shown by comparing to results obtained from conventional dead oil low shear data.