bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gelation Kinetics of an Organically Cross-Linked Gel at High Temperature and Pressure
Authors: Al-Muntasheri G. A. , Nasr-El-Din H. A. , Zitha P. L. J. 
Published: December 2007

AbstractDue to their thermal stability, organically cross-linked gels have been used to control water production in high temperature applications. Most of these gels consist of a polyacrylamide-based polymer and an organic cross-linker. Polyethyleneimine (PEI) has been used as an organic cross-linker for polyacrylamide-based copolymers.Recent work indicated that PEI can form ringing gels with polyacrylamide homopolymers (PAM). However, no study reported on the kinetics of PAM/PEI gels. The gelling system examined in the present study is based on a PAM cross-linked with PEI. This paper will show for the first time the possibility of cross-linking polyacrylamide with PEI at high temperatures and pressures.Therefore, the gelation time of the PAM cross-linked with PEI at high temperatures up to 285°F (140°C) and pressures up to 435 psi (30 bars) was measured. The effects of polymer concentration, cross-linker concentration, temperature, salinity and the initial degree of hydrolysis of the polymer on the gelation time were examined in detail. All measurements were conducted in the steady shear mode at low shear rates using an Anton-Paar high temperature/high pressure viscometer. C13 Nuclear Magnetic Spectroscopy (C13 NMR) was extensively used to relate gelation time to changes in the structure of the polymer and hence, explain the variation in the gelation time in terms of the system chemistry.Thermally stable gels were obtained by cross-linking PEI and PAM at high temperatures (120°C) for at least 2 weeks. The activation energy of this system at high temperatures in distilled water was found to be 71.3 kJ/mol. The addition of sodium ions increased the activation energy to 88 kJ/mol.
Log Data Preparation: A Real Opportunity To Save Money and Time
Authors: Barbato R. , Quaglia A. , Porras J. C. , Panesso R. , Soria J. 
Published: December 2007

Abstract
In spite of new or old planning philosophies, log data preparation has been overlooked by a lot of players in the oil business. We are not speaking about conventional data preparation, such as depth shifting, normalization or editing, for these are very well taken care of in most projects. We want to go a step back. We are talking about the initial phase, even previous to vectorización. Well logs have a large variety of users but each of them has different needs and use different parts of the logs with different goals. Doing a gross generalization, Petrophysicists will go after most curves, use detailed-scaled logs (1:200), and concentrate in the reservoir area; geologists will usually go for SP, GR, resistivity and porosity logs in a reservoir-to-formation scale, using intermediate to large scale logs (1:500 and 1:1000); geophysicists mostly use large scales (1:1000 to 1:5000); and drillers use 1:10.000 or larger scales and mostly GR, density and sonic logs; and so on.
If the original digital data exists, every one will be happy, but if only analogical data exist, problems will rise because every specialist will try to get what he or she needs as fast as possible and with the quality that he or she needs without taking into account the needs of other specialists or the organization mid-to-long term needs. No one can blame them since there are deadlines and goals to achieve, but for the next project in the same area it will happen again….and again….and again. At the end the logs are digitized using completely different approaches leading to a chaotic mosaic of pieces of logs that do not match anyone's final needs, the data base becomes a mess and all upcoming projects will always have problems with log data.
In this work, a FRONT END LOADING approach is proposed and applied, leading to a group of specifications and best practices to be used as guidelines in well log preparation for Reservoir/Field/Asset/Corporation well log databases. The application of these guidelines will satisfy the needs of any well log user, optimize database management and improve the productivity of project teams. These best practices are supported by years of time-saving and technical improvements in a large numbers of projects. Time and money invested at the beginning of the projects will become even larger time and money savings at the long run.
Calibration of Parameters Used in the Processing of Nuclear Magnetic Resonance Data, Acquired in Heavy- to Extraheavy-Oil Reservoirs, by Integrating Core, Production, and Conventional Log Data With Magnetic Resonance Data—Orinoco Belt, Eastern Venezuela
Authors: Hernandez H. , Odreman J. , Moya Y. , Tineo F. 
Published: December 2007

Abstract
Permeability, fractional porosities, irreducible water saturation and fluid viscosity calculations, derived from Nuclear Magnetic Resonance (NMR) data, are largely dependant on T2 decay rates (in NMR terminology, T2 is the time constant that characterizes the decay rate of the echo train).
NMR models show that the T2 of oil is directly proportional to porosity and permeability and inversely proportional to viscosity. As oil viscosity increases, T2 decreases and the NMR signal of heavy oil may coincide with the clay bound and capillary bound water signals or even be much faster. Therefore, conventional parameters and cutoffs, used in the calculations of petrophysical properties, generally cause underestimation of porosity and permeability.
By integrating core, production and conventional log data with NMR data it will be able to determine appropriate parameters and cutoffs and also generate a model to be used in the calculations of petrophysical properties from NMR data.
The correct parameters, cutoffs and generated model can later be used to process NMR data from other wells where core and or production data is not available.
Sand Mapping Using Multiwavelet Seismic Trace Decomposition and Reconstruction
Authors: An Ping 
Published: December 2007

Abstract
A seismic trace is decomposed into a set of Ricker wavelets of different dominant frequencies and amplitudes. The seismic trace can then be accurately reconstructed with all the wavelets in the set of wavelets. With certain targeted objective in mind, a new seismic trace can be reconstructed with a selected subset of the wavelets. This reconstruction is found very effective in reservoir sand mapping and characterization. Some examples are demonstrated.
Sanding—Not as it First Appeared
Authors: Abulsayen Ahmed , Enneamy Abdulwahab , Qiu Kaibin , Marsden Rob , Alexander Joe , Safdar Muhammad 
Published: December 2007

Abstract
This paper described a case study involved an investigation in a field in Libya, where massive unexplained fill had been reported accompanying obstruction of production for majority of production wells since the onset of production, indicating possible sanding issues for this field.
To investigate this problem, relevant data from different sources and different domains (i.e., wireline logs, laboratory test data, drilling data, well data and field data) were integrated to generate a Mechanical Earth Model (MEM). This model provided the descriptions of the rock strengths and in-situ stresses in the reservoir formation. Somewhat surprisingly, the model, backed up by the core laboratory test data, observations from core inspection and thin section analyses, revealed the rocks to be extremely hard and strong, and therefore highly unlikely to sand. These findings contradicted with initial impression and previous expectation on this sandstone that it should have been sand-prone formation. Facing these apparent inconsistencies, the investigation moved beyond an initial focus of sanding risk evaluation and sandface completion optimization. The final results revealed that the problems facing the field were other than conventional sanding and formation failure, and that they involved some rather interesting and misleading phenomena, such as precipitation of salt from production, tubing scale, spalling of borehole wall with drawdown and cavings bridge (cavings might fall into and become wedged in the openhole, forming a bridge with no material beneath).
The investigation concluded that installing sand control facilities were unnecessary, which otherwise would have cost millions of dollars without correctly addressing the real problem that this field was facing. The study highlighted the importance of a thorough investigation of the mechanism and source of sanding rather than premature conclusions based initial, and potentially misleading evidence. It also highlighted how the integration of information from different sources and disciplines were able to correctly identify and address a particular borehole fill problem, allowing for optimizing field operations, field management and workover strategies.
Correlations to Predict Frictional Pressure of Hydraulic Fracturing Slurry in Coiled Tubing
Authors: Shah Subhash , Zhou Yunxu , Bailey Michael , Hernandez John 
Published: December 2007

Abstract
Compared with conventional tubing fracturing, coiled tubing (CT) fracturing has several advantages. CT fracturing has become an effective stimulation technique for multi-zone oil and gas wells. CT fracturing is also attractive production enhancement method for multi-seam coalbed methane wells as well as wells with bypassed zones. The excessive frictional pressure loss through CT has been a concern for CT fracturing. CT strings have small diameter and this limits the cross-sectional area open to flow. Furthermore, the tubing curvature causes secondary flow and hence results in extra flow resistance. This increased friction pressure results in high surface pumping pressure. The maximum possible pump rate and sand concentration, therefore, have to be reduced. To properly design a CT fracturing job, it is, therefore, essential to be able to predict the frictional pressure loss through CT accurately.
This paper presents two correlations for the prediction of frictional pressure of fracturing slurries in coiled tubing. One is developed based on full-scale slurry flow tests with 1-1/2-in. coiled tubing and slurries prepared with 35 lb/Mgal guar gel. The extensive experiments were conducted at the full-scale coiled tubing flow test facility. The other correlation is derived from the Srinivasan's friction factor correlation of Newtonian fluid in coiled pipes. The Srinivasan correlation is modified for the non-Newtonian fluids and it further requires an inclusion of the relative slurry viscosities which have been thoroughly evaluated in this study. The proposed correlations have been verified with the experimental data and actual field CT fracturing data. Case studies of wells recently fractured using CT are provided to demonstrate the application of the correlations. The correlations will be useful to the CT engineers in their hydraulics design calculations.
Nanologging: Use of Nanorobots for Logging
Authors: Singh Pratyush , Bhat Sumit 
Published: December 2007

Abstract
The idea of nanotechnology if applied in any of the technological fields will put LWD and MWD as outdated technology and can prove to be a boon for the next technical revolution. Already postulated to be effective in medical science such as destruction of disease causing bacteria or drug targeting, the nanorobots could be used for logging purpose by circulating these nanorobots, which have nonomotors being driven by the ions in the mud or by mud circulation system. Expensive wireline tools are conventionally used in all types of wells to find important formation properties. I have come up with an idea of nanorobots for oil field logging. Nanorobots can eliminate use of these tools, entirely and small particles of order of nanocentimeter can be put in the drilling mud to obtain useful information. These robots equipped with nanosensors could be used to measure various properties of formation, borehole environment, mud properties and many more. Nanorobots can be constructed in a manner so that they possess sensors, on-board driving mechanism and microcomputer as well as interface mechanism from where it can send instructions to microcomputers from surface computers. Transmission to surface is by means of electromagnetic waves and detected by means of probes on surface. They facilitate wire-less communication and real time surveillance. Thus in comparison to the conventional logging they can save rig hours and can be more accurate and precise as compared to presently used techniques like logging while drilling and measurement while drilling. They can move with circulating mud or they can be made to propel or stop by the on-board computer instructions depending upon the measurement to be taken. They will also be able to invade the formation and get important petrophysical parameters.
A Permeability Model for Coal and Other Fractured, Sorptive-Elastic Media
Authors: Robertson Eric P. , Christiansen Richard L. 
Published: December 2007

Abstract
This paper describes the derivation of a new equation that can be used to model the permeability behavior of a fractured, sorptive-elastic media, such as coal, under variable stress conditions commonly used during measurement of permeability data in the laboratory. The model is derived for cubic geometry under biaxial or hydrostatic confining pressures. The model is also designed to handle changes in permeability caused by adsorption and desorption of gases from the matrix blocks. The model equations can be used to calculate permeability changes caused by the production of methane from coal as well as the injection of gases, such as carbon dioxide, for sequestration in coal. Sensitivity analysis of the model found that each of the input variables can have a significant impact on the outcome of the permeability forecast as a function of changing pore pressure; thus, accurate input data are essential. The permeability model can also be used as a tool to determine input parameters for field simulations by curve-fitting laboratory-generated permeability data. The new model is compared to two other widely used coal permeability models using a hypothetical coal with average properties.
Interwell Heterogeneity Analysis by Dynamic Correlation Method
Authors: Liu Mingxin , Liu Y. Z. , Guo Tongcui , Cai Lei 
Published: December 2007

Abstract
A method was tried to analyze interwell heterogeneity economically and conveniently by correlation of injection and production data. The basic idea of this method is that the fluctuations of injection rate of injector and production rate of producer can be regarded as lines of wave changing with time. A correlative coefficient is used to estimate the correlation between the two lines of waves.
Taking a group of injection production wells as a study unit, centered on injection well unit, we calculate the correlative coefficient of performance parameters between production well and injection well in "correlative time window", using the correlative coefficient to reflect the relative extent between the two lines of waves.
We study the reservoir in the following aspects according to correlativity and the delay time when the correlative coefficient reaches best: (1) correlative coefficient was used to distribute the injection rate, and to analyze the effect between injection rate and production rate. (2) The delay time is the effective response time for water flooding when the correlative coefficient reaches best, then we can determine which well has little effective response time, and which well is the main flow direction of injection well flow to. Only if the delay time is zero, can there be obvious flee channels between production well and injection well. (3) The analysis of the reason for minor production, output reducing and lack of injection (4) Evaluation of formation interconnection and identify big pore wormhole. This method has been made into software, it has visual operation interface, which is easy in operation and studying. The diagnostic example of big pore wormhole in china oilfield made an excellent agreement with the tracer result.
Steamflood Trial and Research on Mid-Deep Heavy-Oil Reservoir QI40 Block in Liaohe Oilfield
Authors: Jiuquan An , Li Ji , Jiang Hua 
Published: December 2007

Abstract
In the paper, the implementation process and results of the pilot tests and expanded tests of steam drive in Block QI40 in Huanxiling Oil Recovery Plant of Liaohe Oilfield is analyzed, the patterns and production features of steam drive in moderately deep, medium ~ thick interbedded conventional heavy oil reservoirs after steam huff and puff are studied and the supporting technologies developed during the steam drive in Block QI40 are outlined together with the problems solved by the technologies. Valuable knowledge and experience have been obtained in terms of heavy oil steam drive in moderately deep formations. At the same time, it has been proved that satisfactory development results and reasonable economic benefits can be obtained when steam drive is applied to the moderately deep heavy oil reservoirs after many cycles of huff and puff, providing reliable operational experience and technical support for the commercialization of steam drive in Block QI40 and similar oilfields.
Pioneer Application and Promising Future of Horizontal Water-Injection in China
Authors: Fang Jie , Jia Chengzao , Li Baozhu , Luo Kai 
Published: December 2007

Abstract
The horizontal water injection is utilized in some oilfields worldwide. The successful practices show that horizontal water injection can enhance the injectivity. Especially for the fields in high water-cut stage, horizontal injection can improve the reservoir pressure maintenance level, sweep efficiency, recovery, and achieve good economic benefit. Applications in an oilfield in West China demonstrate that horizontal injection can raise the water injection volume, improve the sweep efficiency. This is the first pioneer case that adopts horizontal injection fieldwide, showing the promising future of horizontal injection in China.
The Research on Asphaltene Deposition Mechanism and Its Influence on Development During CO2 Injection
Authors: Ying Jia , Lei Sun , Liangtian Sun , Lei Huang , Chunxia Huang , Lin Hong 
Published: December 2007

Abstract
Based on high pressure physical property experiments, such as swelling experiment, multi-contact experiment and asphaltene precipitation experiment et al, thermodynamic characteristics of asphaltene precipitation during CO2 injection have been analyzed comprehensively with numerical simulation, which make up the deficiency of analyzing physical and chemical parameters with experiments; adsorption and plugging of asphaltene on rocks and rheology characteristic of oil containing precipitated asphaltene have been studied; the influence of asphaltene deposition on reservoir have been researched; Found on above-mentioned study, the mathematic flow model considering asphaltene deposition has been established. Take one oil field in our country as example, the influence of asphaltene deposition on production dynamics during CO2 injection has been researched. The results were in agreement with field observation and history data, which can be efficient for the further production prediction.
Application and Prospective of Sand Management With Multilateral Wells by Means of Drilling and Completion Technology for EOR in Bohai Bay
Authors: Jiang Wei , Zhou Shouwei , Liu Liangyue , Zhang Chunyang , Fan Baitao 
Published: December 2007

Abstract
This paper summarizes the three big challenges in the development of the oilfields in Bohai Bay: most of the reserve is heavy oil; formation is unconsolidated and lower productivity after sand control operation. Through years of research and improvement, based on serious analysis of reservoir characters and oil production performance, method of drilling and completion and production management, traditional distribution of the mesh of directional well and conventional gravel pack sand control method are changed and an alternation of sand management multilateral technology is adopted to enhance the production and oil recovery with three technology characters: one is the control of the drop of production pressure under the condition of sand management, until this technology is applied in Bohai Bay, remarkable achievement is made in the field of enhance the production and oil recovery for the development of new oil field and the reboot of the older oil field, which has been one of the key technologies to apply to a large scale and continuously improve. It has been exerting a lot of pressure and positive influence on the technology of production, drilling and completion technology, and further performance of the EOR.
Application and Research of Latex Tenacity Cement Slurry System
Authors: Sun Fuquan , Lv Guangming , Jin Jianzhou 
Published: December 2007

Abstract
This article presents the stability research of latex tenacity cement slurry, develops the BCT series stabilizer and studies the performance of the slurry and the set cement. Due to the slurry performance study, it is found the latex material can be evenly distributed in the slurry, which can form a film to bond free water and micro particle, reduce fluid loss and prevent gas migration. Adding other additives to this system, the slurry shows better performance with lower fluid loss, better rheological behavior and adjusting thickening time. Due to the set cement performance study, it is found the latex particle can evenly fill in the fine gap of C-S-H gel. It assembles and forms a film to cover the CSH surface, which can decrease the set cement elasticity coefficient and permeability, improve its impact resistance and anticorrosive properties. Moreover, the application of this latex tenacity cement slurry system is introduced in this article.
Multiple-Stage Fracture Treatment of Horizontal Wells
Authors: Wang Feng , Zhang Yingan , Li Biansheng 
Published: December 2007

Abstract
Aiming at the actuality of horizontal well fracturing modified technology is complicated and limited entry fracture treatment is restricted in internal and overseas low-permeability oilfield currently. The studied and experimented that using packer performed the staged fracturing and corollary technique in annulus between tubing and casing, verified by 23 wells and 41 staged treatments in field with 100% of successful rate and effect of fracturing stimulation is very significantly. The full process of hydraulic motion includes setting, working and releasing were realized by the packer of annulus staged fracturing, and putting into well tools were reduced by horizontal well annulus staged fracturing technology as well as the accident sticking fishing corollary technique has been formed. In addition, annulus fracturing also have advantages of low fluid fraction, improving treatment rate and reducing treatment pressure, etc., multi-fractures removing plugging fracturing stimulation of long perforated interval can be performed, too. Thus, a new method has been developed for the horizontal well fracturing technology.
The fracturing treatment of the horizontal wells is one of the studying focus in domestic and overseas, staged fracturing technology of the horizontal wells applied in the oilfields mostly include horizontal wells selective interval isolation fracturing technology in overseas, changing horizontal wells gel staged fracturing technology in domestic, daqing oilfield horizontal limited entry fracturing technology and so on. At present, the horizontal wells fracturing technology is mainly restricted in limited entry fracturing. What this paper presents is the staged fracturing technology of horizontal wells in annulus between tubing and casing. Annulus treatment can reduce treatment friction efficiently with the ability of improving treatment scale, and supply the technology warrant of improving the horizontal wells development effect in low-pemeability oilfield.