bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kick with Lost Circulation Simulator, a Tool for Design of Complex Well Control Situations
Authors: Petersen Johnny , Rommetveit Rolv , Tarr Brian A. 
Published: December 2007

Abstract
Being able to simulate drilling problems when operating within narrow margins between formation pressure gradients and fracture pressure gradients can cause great savings through improved planning. This is especially the case for HPHT and Deep Water wells. Lost circulation (i.e. underground flow) has in many cases proved to be a significant contributor to complex well control problems and drilling delays.
The advanced kick simulator, RF-Kick, has recently been expanded to include the simulation of massive lost circulation. This tool allows the user to interactively investigate the problems of killing an influx while losses to formation occur. Kill procedures can thus be optimized through simulations.
The fracturing is computed in a simple way. Only three numbers define the fracturing: the Fracture Initiation Pressure, the Fracture Propagation Pressure and the Fracture Closing Pressure. These pressures are supplied by the person using the simulator. The flow into (and out of) the fracture is determined by the flow needed to keep the fracture pressure at the fracture position. A user given fraction of fluid lost to the formation determines the amount of fluid re-entering the well.
This paper presents a description of the model, and a simulation of a representative's deep water well. The simulation starts with a well taking a kick. The well is shut in. As the pressure builds up the formation breaks down and an underground blowout develops. The influx is stopped while limiting the loss to the formation using sufficient flow rate and kill mud. The example describes actions done to lower the pressure at the fracture to stop the loss of fluid, and the careful well operations needed to handle a well with a closing fracture. The simulation finishes when the fracture is closed and all the reservoir fluid has exited the well. Such simulations show the operator what equipment is needed for a successful kill, pump capacity (volume and power), and kill mud (density and volume).
Simulating kick with lost circulation scenarios is novel and a significant contribution. This will enable the industry to perform planning and engineering of complicated well control situations.
P. 25
Integration of Fuzzy Methods into Geostatistics for Petrophysical Property Distribution Simulation of a Reservoir at Exploration Stage
Authors: Zhanggui Lian , Di Jiao , Jun Fan , Jianchun Guo , Kaihong Zhang 
Published: December 2007

Abstract
Theories of fluid flow in heterogeneous porous media show that their transport properties are determined by the structure of spatial correlation in the permeability distribution. Geo-statistical methods have been used to provide equally probable reservoir descriptions that honor available data of a given reservoir for the past decades. During the early exploration stage, the hard data (coring, well testing and well log) often come only from several wells with large well spacing. Though soft data (such as geophysical and geological interpretation, outcrop and seismic data) can be taken into consideration, it is still problematic to characterize a formation by deterministic Kriging or probabilistic simulation, because the formation property spatial variability in different directions is hard to capture by sparse hard data and soft data, especially in lateral direction.
In this paper, fuzzy methods are used to quantify the anisotropy and spatial correlation structure of formation petrophysical properties in a reservoir with several wells and some soft data, and fuzzy methods can be integrated into Kriging, simulation and fractal interpolation. As a result ,some new approaches are suggested and applied to the prediction of the formation property distribution in Shanlan reservoir, West China. Compared to the same methods without fuzziness involved, the techniques show some more robustness and reliability in characterizing spatial variability and structure of the properties and in reservoir characterization.
High Angle Drilling In Severely Depleted Reservoirs
Authors: Bonnett Nigel , Williamson Bob , Oakes Peter 
Published: December 2007

Abstract
The Beryl Field was discovered in 1972, with the Alpha platform coming on stream during 1976 and the Bravo platform eight years later. Platform drilling operations (redrills, following slot recovery) are still ongoing, with the new wells and their associated targets becoming increasingly complex directionally (Designer Wells), in striving to recover the remaining attic oil. These wells generally tend to be horizontal through the reservoir; unless a number of discrete fault terraces are to be penetrated, when a highly deviated wellpath becomes more advantageous, on a productivity basis. However, the major added complication, is the continual depletion of pore pressure of the targeted reservoir sequences. It is now a common feature of these platform wells, to be drilling through the reservoir section with positive pressure differentials in excess of 2000 psi. This paper examines the mature drilling operations on the Beryl Platforms, discusses the philosophy developed to successfully drill under these severe conditions and reviews the operations over the two-year period commencing June 1995.
P. 543
Wireline Tractor Production Logging Experience in Australian Horizontal Wells
Authors: Local Eddie 
Published: December 2007

Abstract
New wireline tractor technology has been developed and used successfully in Australia to deploy production logging tools in horizontal wells. The results of operations in the Wandoo field in Australia are presented. The dynamics of tractor operations have been modelled, and field data has been used to validate the model and to quantify borehole friction coefficients. The model may be used to assist job planning and to assess the feasibility of deployment by wireline tractors in general situations.
Innovative Live Well Perforating System Used in the Statfjord Field
Authors: Kleppa Erling , Svane Elisabeth , Varhaug Helge 
Published: December 2007

Abstract
This paper describes a system developed for live well perforating and presents several case histories of its usage. The system has currently been used on 13 jobs on the Statfjord field. A total of 2106 m has been perforated, and the longest interval in one run has been 277 m in this particular field. The system has been used both for initial perforation on new wells and reperforation in live wells or in combination with zone isolation. Both injectors and producers have been perforated using this system.
An optimum perforating strategy can have significant impact on the economy of a well. During the past few years, techniques to perforate wells without having to use kill fluid have been developed. This reduced the cost and the problems that can occur as a result of kill the well. Kill fluid can not only affect the productivity of the wells, but may also create problems when produced back to the hydrocarbon process equipment. In addition, it has been noted that a higher and more stable sand free production rate will be obtained if the entire interval is perforated simultaneously.1
Perforating underbalanced allows the debris in the perforating tunnel to be cleaned more easily.2 If the well does not have to be killed, considerably less formation damage will occur, and the costs of kill fluid, lifting the well, and handling of the returned kill fluid are also eliminated.
This paper describes a new live well perforating method deployed with a hydraulic workover unit, that allows long intervals to be perforated in wells with complicated well trajectories
A Static Slickline-Retrievable Wellhead Plug System for Use with Horizontal Trees in Offshore Systems
Authors: Vick James , Robb Ewan , Thomson David , Collie Graeme 
Published: December 2007

Abstract
One of the recent enhancements to offshore completion technology has been the development of horizontal subsea trees1 in which the gate valve barrier of a traditional tree has been replaced with a plug system that can be deployed and retrieved with slickline. Traditional plug systems employed elastomeric-type sealing systems. However, because fields with more extreme environments are now being developed, industry trends are showing more metal-to-metal (MTM) seals being requested.
A new static wellhead plug system, which has been developed for horizontal tree configurations, offers MTM sealing capability under all operational conditions. Also, it can be used as a primary barrier that permits vertical access to the well for slickline or coiled tubing well intervention once retrieved through a riser string. This paper will provide background, application, features, testing, and advantages of the new slickline-retrievable static wellhead plugs as well as provide case history data.
Utilisation of a Pseudosonic Curve to Replace Wireline Sonic: a Case History
Authors: Quagliaroli R. , Carugo C. 
Published: December 2007

Abstract
A pseudosonic curve derived from standard drilling parameters has been computed in near real to replace wireline Sonic in a well drilled in offshore Norway.
The pseudosonic curve was obtained using SLDT (Surface Logging Delta Time), a new methodology jointly developed by AGIP and Baker Hughes INTEQ. It is based upon a theoretical Drilling Model that describes the cutting action of various drilling bits using a rock mechanics approach. It employs surface drilling measurements and bit geometry as input data to derive information about formation velocities.
The results obtained for the norwegian well using this novel technology are very encouraging. The ITT (Integrated Transit Time) computed from SLDT data showed an excellent agreement with the ITT derived from VSP run at TD (maximum 0.5% of difference along the well and 0.15% at TD, corresponding at only 2 msec). Moreover, the SLDT curve compared with the sonic wire-line recorded in the 8" 1/2 phase, shows a very good correlation both in absolute values and trend.
The pseudosonic curve furnished a reliable correlation while drilling to offset wireline measurements and to seismic sections.
P. 273
Computer Aided History Matching of a Real Field Case
Authors: Grussaute Th. , Gouel P. 
Published: December 2007

Abstract
This paper presents the application of a semi-automatic history matching tool to real field cases. The process of history matching a reservoir model is a difficult and time-consuming step in the course of a reservoir engineering study. The gradient method has now been widely accepted as an efficient way of aiding the reservoir engineer during this process. The sensitivities of the dynamic observations with respect to the model parameters give some very valuable qualitative and quantitative information about the best history matching parameters.
A history matching tool has been developed to make the most of the gradient information. Tests are carried out on two 3D 3-phase field cases in real industrial conditions. We show that the computing times are still a critical issue for the validity of the method. Results and methodology are presented and the practical benefits of such techniques for the reservoir engineer are assessed.
P. 121
A Novel Technique for Single-Selective Sand Control Completions Cuts Completion Costs in Half: Method Development and A Case History from the Gulf of Mexico
Authors: van Wulfften Palthe P. , Smith J. , Achee T. , Dancause C. , Parlar M. 
Published: December 2007

Abstract
Single-selective sand control completions can be very expensive particularly in offshore environment where rig costs are high. Such completions traditionally involve completion of each zone separately, with multiple trips in and out of the hole. A conventional single-selective completion typically involves a round-trip for each of the following:perforating the lower zone,packing (gravel-frac-) the lower zone,running and setting the packer plug to isolate the lower zone,perforating the upper zone,packing (gravel-/frac-) the upper zone, and finally running in with production string.
The whole process takes anywhere from 8 to 10 days.
In this paper, we present a new technique for single selective sand control completions in cased holes utilizing a single-trip perforating and packing technique with a zonal isolation device for the lower zone followed by perforating with wire line and running in with gravel-pack assembly on production string to complete the upper zone. In this fashion, the completion of the lower zone is reduced from 3 trips 1 trip, and that of the lower zone is reduced from 2.5 to 1.5 trips; with the net savings of 3 trips. This technique required some modifications in the production seal assembly so that the production string could be used as the work string during gravel- or frac-packing. This new completion method was a result of close collaboration between the operating and service company, and has recently been used for frac-pack completion of two zones in a well in the Gulf of Mexico. Completion costs were reduced by 30% and completion time was reduced by 50% compared to alternative traditional methods. Details of tool modifications and the field application are discussed along with economic comparison to earlier practices.
P. 191
History of and Applications for a Coil-Tubing-Conveyed, Inflatable, Selective Injection Straddle Packer
Authors: Loughlin Michael J. , Plante Mark 
Published: December 2007

Abstract
This paper outlines the history, deployment into a live well, and operation of a through-tubing selective injection tool. This tool is an inflatable, re-settable, coiled tubing-conveyed straddle packer assembly designed to run through production tubing and isolate a portion of perforated casing to allow precise injection of stimulation or water block chemicals.
The paper includes a description of 27 field runs of this tool from 1995 through June 1998 and examines the five case histories listed below in more detail:
Gravel pack screen acid wash job Through-tubing selective water shut-off polymer job through casing perforations Through-tubing job to remedially set an external Casing packer (ECP) after completion Open-hole selective stimulation job Through-tubing selective stimulation job through casing perforations.
P. 229
Assessing the Feasibility of a 4D Seismic Reservoir Monitoring Project
Authors: Blonk B. , Calvert R. W. , Koster J. K. , van der Zee G. 
Published: December 2007

Abstract
In many, but not all cases, time-lapse (4D) seismic data can be used with commercial advantage to monitor reservoir changes between and away from the wells. In order to avoid disappointment we need to recognise the favourable cases before starting a time-lapse seismic monitoring project. We aim to assess if a particular seismic survey may be suitable as a base survey and we discuss a 4D-feasibility method, which can be used to predict if predicted changes in the reservoir's acoustic properties could be interpreted using a repeat seismic survey. To this end, seismic, rock and fluid property data, as well as results from the flow simulator are integrated. The method can be used to reduce the risk of shooting a repeat survey that would not show what was being sought, and can also help in deciding on the proper timing for an eventual reshoot. Furthermore, the method is also valuable for assessing data quality before quantitative interpretation studies. The method is illustrated by examples from the Middle East and the North Sea.
Effect of Reservoir Fluid Production on Gas Hydrate Phase Boundaries
Authors: Ostergaard K.K. , Danesh A. , Tohidi B. , Todd A.C. , Burgass R.W. 
Published: December 2007

Abstract
An integrated theoretical and experimental study has been conducted to examine the effect of reservoir fluid production on the hydrate free zone of produced fluids. The paper presents the results of pressure depletion and surface separation of black oil, volatile oil, and gas condensate on the hydrate free zone. The results show that pressure depletion at reservoir temperature has only an insignificant effect on the hydrate free zone of produced fluids, whereas for surface separation, the hydrate free zone of the separated fluids may differ from that of the feed.
P. 507
Combining Innovative Technologies To Maximize Scale Squeeze Cost Reduction
Authors: Bourne Hugh M , Booth Steven L , Brunger Alan 
Published: December 2007

Abstract
The continual need to reduce oil production costs has led Mobil North Sea Limited (MNSL) and TR Oil Services Limited (TROS) to develop a new strategy for maximising the efficiency of scale squeeze treatments on the Beryl Field. The strategy combines the advantages of enhanced precipitation scale inhibitors with a squeeze performance enhancer. The development and use of innovative chemical technologies such as these, has provided the industry with an important new route to achieving cost reduction goals.
The enhanced precipitation scale inhibitor in use on Beryl has been reformulated to provide optimum performance over an eight-hour shut-in period. Core flood studies have shown that the lifetime achieved through use of the optimised product is, in fact, longer than that seen with the original scale inhibitor, which utilised an eighteen-hour shut-in period. The ten-hour reduction of the soak time has meant that production down time during squeeze treatments has been dramatically reduced.
The scale squeeze enhancer has been developed in conjunction with BP Chemicals and BP Exploration to promote the retention of scale inhibitor during a squeeze treatment. Experimental work has indicated that application of the squeeze enhancer in conjunction with the reformulated inhibitor package will result in significantly longer squeeze lifetimes than those previously seen on Beryl.
Following the laboratory work, several field trials in the Beryl Field have been performed. The correct deployment of the enhancer with the precipitation squeeze inhibitor has resulted in a significant reduction in the re-treatment interval and well clean up times leading to significant cost savings.
Electrical Measurements in the 100Hz-10GHz for Efficient Rock Wettability Evaluation
Authors: Bona N. , Rossi E. , Capaccioli S. 
Published: December 2007

Abstract
This paper summarises the experimental and theoretical study conducted in ENI/Agip to investigate the effect of rock wettability on the dielectric response of water and oil saturated core samples. The aim of the study was to evaluate a dielectric technique not previously applied to wettability determination as a practical alternative to conventional tests, and to ascertain the consequent economic and technical benefits in reservoir appraisal.
Use of Tracers in Drilling Muds to Allow the Estimation of In-situ Formation Water Compositions From Drilling-Mud-Contaminated Formation Water Samples
Authors: McCartney Ross A. , de L.G. Solbé Michael J. 
Published: December 2007

Abstract
It has been proposed (e.g. Ref. 1) that formation water compositions can be calculated from drilling mud contaminated sample analyses using a simple mixing model if a tracer is added to the drilling mud. In this paper we test this proposition using field data obtained from 18 wells on the edge of the Irish Sea Basin. Our evaluation shows that, in some circumstances, it is not valid to apply the simple model to Na, Ca, Mg, K, Sr, Cl, Br and SO4 data. Similarly, we have found that apparent mixing trends in data can be misleading and it is important to attempt to validate the results of contamination correction calculations by alternative methods to support formation evaluation and production operations.
Mechanism of a Novel Shear-Sensitive Plugging Fluid To Cure Lost Circulation
Authors: Quinn David , Sunde Egil , Baret J. F. 
Published: December 2007

Abstract
Massive lost circulation is a major and costly drilling problem. The drilling community needs a single fluid which can be pumped through the drill bit, curing losses instantly. This paper describes a novel shear-sensitive plugging fluid designed to gel rapidly after passing through the bottom hole assembly (BHA) in normal drilling operations, thus curing massive mud losses.
This fluid is based upon what is termed a ‘loose’ invert emulsion. The continuous phase provides an encapsulation medium for a crosslinker. The internal phase of the fluid consists of a high concentration of a polymer and the interfacial tension between the two phases is maintained by a concentration of a lipophilic surfactant.
The pressure drop experienced by the fluid as it passes through the BHA triggers the inversion of the emulsion to a direct emulsion. This inversion releases the encapsulated crosslinker into the water phase. The result is a rigid gel which can be designed to generate a solid structure from one to ten minutes after passing through the BHA. The set time is virtually independent of temperature.
This paper describes the perceived mechanism, placement and data from field trials demonstrate the potential of the fluid under difficult conditions.
High-Pressure/High-Temperature Rheology of Na+-Montmorillonite Clay Suspensions
Authors: Rossi S. , Luckham P. F. , Zhu S. , Briscoe B. J. 
Published: December 2007

Abstract
This paper describes the rheological behavior of Na+-montmorillonite suspensions in the presence and absence of different electrolytes (NaCl, KCl, LiCl) and a polyethylene oxide type polymer under high pressure and high temperature conditions. Shear stress - shear rate flow curves were obtained for 5% (w/w) Na+-montmorillonite suspensions for temperatures up to 120°C and pressures up to 1000 Bar. The data was fitted to both the Bingham model and Herschel-Bulkley model, from which the corresponding rheological properties were derived. Results indicate that the addition of electrolytes and a rise in temperature leads to an increase of the yield stress, due to flocculation of the clay suspension and thermal induced swelling respectively. However, the gel structure may be broken down upon the application of pressure depending upon the electrolyte. It was found that the addition of KCl to the Na+-montmorillonite suspensions originated a strongly flocculated structure, less sensitive to pressure variations, where swelling was reduced at higher temperatures. An aggregating behaviour at high temperatures was observed for the clay suspensions containing PEO and either NaCl or LiCl, attributed to the theta-temperature of PEO. At a lower temperature, the presence of PEO on the clay particles allowed the clay suspension to recover after the pressure was applied, preventing irreversible aggregation of the suspension. The rheological properties for PEO stabilised Na+-montmorillonite suspensions containing KCl were very slightly affected under HPHT conditions, in contrast to the presence of other electrolytes (NaCl, LiCl). Swelling of the clay particles was strongly inhibited by the combined use of KCl and PEO. Estimation of the rheological properties of Na+-montmorillonite suspensions in the presence of PEO with the different electrolytes led to the conclusion that the extent of swelling occurs in the order KCl &lt; NaCl &lt; LiCl, coinciding with the order of increasing size of the hydrated cation.