bluuebunny/crossref_metadata_2025_split huggingface dataset:
Real-Time Prediction of Shut-in Production From Hurricanes in the Gulf of Mexico
Authors: Watson C. C. , Johnson M. E. 
Published: December 2007

Abstract
Accurate prediction of damage to petroleum production infrastructure from hurricane winds, waves, and storm surges has numerous applications to facility design, production planning, and the financial markets, among others. Here we describe a system for the estimation of damage, repair time, and shut in production using a numerical hurricane model and damage models for various infrastructure components. The system was designed and pilot-tested using data from Hurricane Ivan (2004) and prior storms, and validated operationally in forecast mode during the 2005 hurricane season. The petroleum extraction and distribution systems in the Gulf of Mexico as of 1 May 2005 were stored in a geographic information system. Damage to that infrastructure, consisting of over 50,000 elements, was computed using a three-dimensional physics hurricane model driven by forecast track and intensity data. The resulting damage statistics were then used to derive shut in production predictions for the Katrina and Rita landfalls, the results of which were posted on a web site in real time. The performance of the real time forecast system has been compared to reported statistics and found to accurately predict shut in production, especially using 24 hour forecasts through immediate post storm meteorological data. The validated shut in production prediction model was then applied using the 155 years of existing historical data to produce estimates of the magnitude and frequency with which significant production disruption would have been expected from the Gulf of Mexico facilities, given the present distribution of platforms and on-shore facilities. These frequencies indicate that significant disruptions of production on the order of magnitude seen in 2005 would be relatively common occurrences, given the performance of the infrastructure in recent events and historical hurricane activity. This implies that both design criteria and management of the petroleum production and distribution infrastructure should be revised.
A Four-Component, Two-Phase Flow Model for CO2 Storage and Enhanced Coalbed Methane Recovery
Authors: Seto C. J. , Jessen K. , Orr F. M. 
Published: December 2007

Abstract
Injection of CO2 into deep unminable coal seams is an option for geological storage of CO2. Moreover, injection of CO2 may enhance the recovery CH4 in these systems making coal reservoirs interesting candidates for sequestration.
New analytical solutions are presented for two-phase, three- and four-component flow with volume change on mixing in adsorbing systems. We analyze the simultaneous flow of water and gas containing multiple adsorbing components. The displacement problem is solved by the method of characteristics. Mixtures of N2, CH4, CO2 and H2O are used to represent enhanced coal bed methane recovery processes. The displacement behavior is demonstrated to be strongly dependent on the relative adsorption strength of the gas components.
In ternary systems, two types of solutions result. When a gas rich in CO2 displaces a less strongly adsorbing gas (like CH4), a shock solution results. As the injected gas propagates through the system, CO2 is removed from the mobile phase by adsorption, while desorbed gas propagates ahead of the CO2 front. The adsorption of CO2 reduces the flow velocity of the injected gas, delaying breakthrough and allowing for more CO2 to be sequestered per volume of CH4 produced. For injection gases rich in N2, a decrease in partial pressure is required to displace the preferentially adsorbed CH4, and a rarefaction solution results.
In quaternary displacements with injection gas mixtures of CO2 and N2, the relative adsorption strength of the components result in solutions that exhibit features of both the N2-rich and CO2-rich ternary displacements.
Analytical solutions for enhanced coal bed methane (ECBM) recovery processes provide insight into the complex interplay of adsorption, phase behavior and convection. Improved understanding of the physics of these displacements will aid in developing more efficient and physically accurate techniques for predicting the fate of injected CO2 in the subsurface.
Jetting of Structural Casing in Deepwater Environments: Job Design and Operational Practices
Authors: Akers T. J. 
Published: December 2007

Abstract
Structural casing jetting operations have become commonplace in deepwater environments. Having originated in the Gulf of Mexico, structural casing is now jetted in most deepwater basins in the world. Very little literature has been published regarding jetting practices. Indeed, jetting operations remain as much an art as a science to a large degree. This paper reviews current deepwater structural casing jetting job design and operational practices. Also included are several case histories of jetting failures presented in order to share learnings with the industry and to stimulate the sharing of learnings and practices.
A New Disc One-Cone Bit
Authors: Hu Qin , Liu Qingyou 
Published: December 2007

Abstract
With exploration moving into deeper waters, deserts and plateaus, the geological condition and natural environment faced with by the drilling operation get more complex and worse, so that the difficulty of exploration and development is increasing and the more requirements are put forward to drilling tools. Owing to the extensive application of slim-hole drilling in the world, it is the one of the most important researches for rock bit suppliers and rock bit researchers to develop the efficient small diameter bit.
According to analysis, the rock-breaking efficiency has important relationship with tooth structure and arrangement of teeth. However, owing to the lack of fundamental change on the tooth surface structure of bits in the past tens of years, the drilling speed has nearly not been raised in some special formations. So the new structure of tooth surface must be sought according to the new knowledge for rock-breaking mechanism so as to raise the drilling speed and drilling footage under special environment and some special formations. The disc bit is just the bit with brand-new tooth structure.
After some researches on disc bit and one-cone bit have been done, Southwest Petroleum University (SWPU) has developed a new small size bit with high rotary speed, named disc one-cone bit, which combines the advantages of both one-cone bit and disc bit. This new bit will have expansive application prospect in deep drilling, ultradeep drilling and slim-hole drilling because of its less torsion, higher bottom-hole coverage coefficient and longer bearing life.
In this paper, the experimental study on rock-breaking mechanism of disc one-cone bit is introduced emphatically.
Design and Demonstration of Creating Underground Gas Storage in a Fractured Oil Depleted Carbonate Reservoir
Authors: Xiao Guo , Zhimin Du , Ping Guo , Yuhong Du , Yu Fu , Tao Liang 
Published: December 2007

Abstract
The supply-demand misbalances of natural gas in China require the creation of underground gas storages (UGS) available during peak winter demand and these UGS will probably play an important role in China natural gas market development. As far as know, among existing UGS in China, fractured oil depleted carbonate reservoir converted into UGS is unprecedented. In this paper, a simulation study using both 3D full-field black oil reservoir model and full-field multi-component reservoir model were undertaken to evaluate and demonstrate feasibility of creating UGS in a buried hill fractured oil depleted carbonate reservoir with bottom water, sufficient closure, a good quality and tight cap rock. History matching of the reservoir and single well pressure, water cut, liquid production rate was performed with the full-field black oil reservoir model. The full-field multi-component reservoir model was used to determine total gas storage capacity, working gas capacity, deliverability and injection capacity of the UGS. The simulation study characterized the UGS working mechanism, analyzed its sensitivity, optimized its design parameters, predicted field performance under various operating conditions and recommended the optimized developing UGS plan. Effects of the other three buried hills on the UGS are also incorporated into the two reservoir models. CNPC is further verifying our research efforts to decide duration of the UGS project.
Improved Density Processing for LWD Density
Authors: Desport O. , Crowe J. 
Published: December 2007

Abstract
Density measurements are intrinsically sensitive to standoff. In wireline logging, it is possible to have the detectors on a pad, reduce the standoff to a minimum, and correct for other effects with a high-level of accuracy. Logging while drilling (LWD) is more challenging because the standoff is much more important than with wireline tools, even in the case of a stabilized tool. The traditional spine-andrib technique loses accuracy with high standoff and can be clearly seen with LWD measurements. The common effects are separation between the quadrant densities, density images dominated by eccentricity, and undercorrected density in sliding zones. Image-derived processing, implemented by selecting the sectors where the tool is the closest to the borehole, greatly improves the LWD density measurements but does not solve the case where standoff is too high in every sector or when the tool is sliding. It also does not correct the density image. The processing method presented in this paper offers a different approach to this problem, and the information from the sector measurements is used to build up a more stable density correction than the traditional spine-andrib algorithm. This new technique can be applied to the quadrant densities as well as the sector densities.
This processing method can be applied to old or new wells. With the improved robustness to standoff, most of the sliding zone can be corrected by making LWD density in formation evaluation much more accurate. Using the quadrant density corrections, an estimation of uncertainty of the correction can be computed, which can be very useful in the sliding zone, where only one density value is available.
This processing method was applied in two field studies in Nigeria and good density data were recovered in every well in all the zones with high standoff, including the sliding zones. The few wells in this field where both wireline and LWD logs were acquired confirmed the quality and accuracy of the corrected LWD density measurements.
Differential Cased Hole Sonic Anisotropy for Evaluation of Propped Fracture Geometry in Western Siberia, Russia
Authors: Nikitin A. , Pasynkov A. , Makarytchev G. , Maniere J. , Kalyanaraman R. Sunder , Tcherkashnev S. 
Published: December 2007

Abstract
In a waterflooded reservoir, hydrocarbon recovery optimization is impacted by well spacing and hydraulic fracture extent. An excessive fracture length may lead to an earlier than desired increase in water cut. Uncertainty in propped fracture dimension is related to the distribution of stresses and elastic properties, as well as fluid leak off. Those factors have strong implication on proppant distribution, especially when larger size proppant are used. Although the latter could lead to more conductive fractures, they could also bridge at the wellbore, impeding both lateral and vertical extent.
Differential cased hole sonic anisotropy (DCHSA) combines the use of cross-dipole shear sonic analysis carried out before and after hydraulic fracturing and adequately supported by other logs (ultra-sonic cement evaluation) to infer the change in anisotropy; the latter anisotropy includes the creation of a propped width. While the methodology has been used in carbonates, very few cases of its application in turbidites have been documented.
Differential cased hole sonic anisotropy (DCHSA) can be determined from analysing cross-dipole shear sonic data acquired before and after hydraulic fracturing. From analysis of other log data, such as the ultra-sonic cement evaluation tool, it is possible to infer change in anisotropy, which can indicate the creation of a propped fracture.
In this paper, the results from a DCHSA and hydraulic fracture campaign in a Western Siberian oil field are presented. In this field, the common well development practice consists of multiple, large job fracturing treatments, ranging from 100 to 300 tons, using large sized proppant. It is generally believed that a high stress barrier, above and below reservoir interval, will facilitate the bridging of proppants, and will cause an artificial barrier. Planar 3D models that incorporate stress detail, moduli width calculation, 2D flow proppant tracking and bridging criteria are available to the industry, but do need extensive set of accurate parameters. These models will be greatly enhanced by calibration from direct measurements of the fracture geometry. DCHSA has proved instrumental in detecting fracture induced anisotropy. Fracture heights were modeled with the expected treatment pressures. The outcome proved a valuable methodology that decreased the operational and production risks that are associated with hydraulic fracturing using large proppant sizes.
Improved Acid Diversion Design Using a Placement Simulator
Authors: Glasbergen Gerard , Buijse Marten 
Published: December 2007

Abstract
In matrix-acidizing long intervals, diversion is essential to obtain good placement of the reactive fluids. Over the years, several diversion techniques have been applied, resulting in improved zonal coverage. These diversion methods can be divided in mechanical methods such as the use of balls to seal the perforations and chemical methods such as gelled fluids.
In the design of matrix acid treatments, placement models that predict the zonal coverage of the fluids are of great help. These models improve the understanding of the complex processes and will help to improve the design of matrix-acid treatments. For studying diversion effects, correct modeling of the diversion methods in a placement simulator is essential. We have developed such a fluid placement simulator (FPS) that contains models for the different diversion methods.
In this paper, we will give an overview of the different diversion methods and their application. Further, we will discuss the implementation of the models in a comprehensive FPS. We will show how this simulator can be used to optimize placement and diversion. Validation of the models will be presented based on the analysis of two case histories.
In an acid treatment, the fluid diversion design is often based on guidelines, rules-of-thumb, and an intuitive idea on how diversion "works." Simulators are not used, usually because they are not available. However, the use of a diversion simulator will show that many of the guidelines and intuitive ideas are wrong, or at least incomplete; this will be illustrated with example calculations.
History Matching Using the Ensemble Kalman Filter on a North Sea Field Case
Authors: Haugen V. , Natvik L. -J. , Evensen G. , Berg A. , Flornes K. , Nævdal G. 
Published: December 2007

Abstract
Recently, the ensemble Kalman filter (EnKF) has been examined in several synthetic cases as an alternative to traditional history matching methods. Results from these studies indicate that the method can be useful for estimation of permeability and porosity fields.
Contrary to other history matching methods, the EnKF provides an ensemble of model realizations containing information of the uncertainty in the estimates. Moreover, the data is processed sequentially, which makes it possible to always have an updated model conditioned on the most recent production data. The method therefore seems promising for real time reservoir management. This paper presents a successful study for a North Sea field case, where real production data have been assimilated using EnKF.
Technologies for Arctic Offshore Exploration & Development
Authors: Matskevitch Dmitri G. 
Published: December 2007

Abstract
Exploration and development of hydrocarbon reserves in the Arctic seas are challenged by a harsh environment including presence of ice and icebergs, permafrost, low temperatures, and extended periods of darkness. Remoteness and ecological considerations make activities in the Arctic even more difficult. Advanced technologies, non-traditional technical solutions and flawless execution are required to make any major project in the Arctic a success.
Understanding the difficulties associated with implementing an offshore project in the Arctic comes with experience. In ExxonMobil's case, this results from 40 years of Arctic field operations and associated research. This paper discusses the Arctic technologies developed to support ExxonMobil exploration and development activities in the Arctic seas.
ExxonMobil's Arctic offshore activity started in 1966 with the installation of the ice-resistant Granite Point offshore platform, which is still producing oil in Cook Inlet, Alaska. Since then ExxonMobil has constructed and drilled from artificial islands in shallow arctic waters, drilled in iceberg prone regions off Greenland, Canada and Norway, designed and installed the first iceberg-resistant gravity-based platform on the Grand Banks, installed an ice-resistant production platform and the first in-ice SPM offshore loading facility offshore Sakhalin Island, and continued to develop methodology to provide rational design criteria for ice-resistant production platforms. Development of design criteria and the selection of the most reliable and cost-effective technical solutions for arctic offshore projects required data from numerous field expeditions, model tests programs, field measurements, and observations from existing offshore structures. These studies were carried out under the supervision of ExxonMobil research staff.
Arctic marine transportation systems are also an important element for many offshore and near-shore projects in remote areas where the construction of export pipelines is prohibitively expensive. The "Manhattan" tanker trials in 1969–70 in the US and Canadian Arctic and the 2002 "Primorye" trials in the Tatar Strait have helped ExxonMobil develop safe and reliable technologies for hydrocarbon transportation in ice-infested waters.
Accurate Detection and Spatial Delineation of Thin-Sand Sedimentary Sequences via Joint Stochastic Inversion of Well Logs and 3D Prestack Seismic Amplitude Data
Authors: Merletti G. D. , Torres-Verdín C. 
Published: December 2007

Abstract
We describe the successful application of a new pre-stack stochastic inversion algorithm to the spatial delineation of thin reservoir units otherwise poorly defined with deterministic inversion procedures. The inversion algorithm effectively combines the high vertical resolution of wireline logs with the relatively dense horizontal coverage of 3D pre-stack seismic amplitude data. Multiple partial-angle stacks of seismic amplitude data provide the degrees of freedom necessary to estimate spatial distributions of lithotype and P- and S-wave velocities in a high-resolution stratigraphic/sedimentary grid. In turn, the estimated volumes of P- and S-wave velocity permit the statistical co-simulation of lithotype-dependent spatial distributions of porosity and permeability.
The new stochastic inversion algorithm uses a Bayesian maximization criterion to populate values of lithotype and P- and S-wave velocities in the 3D simulation grid between wells. Property values are accepted by the Bayesian selection criterion only when they increase the statistical correlation between the simulated and recorded seismic amplitudes of all partial-angle stacks. Furthermore, inversion results are conditioned by the predefined measures of spatial correlation (variograms) of the unknown properties, their statistical cross-correlation, and the assumed global lithotype proportions.
Using field data acquired in a fluvial-deltaic sedimentary rock sequence, we show that deterministic pre-stack seismic inversion techniques fail to delineate thin reservoir units (10-15m) penetrated by wells because of insufficient vertical resolution and low contrast of elastic properties. By comparison, the new stochastic inversion yields spatial distributions of lithotype and elastic properties with a vertical resolution between 10-15m that accurately describe spatial trends of clinoform sedimentary sequences and their associated reservoir units.
Blind-well tests and cross-validation of inversion results confirm the reliability of the estimated distributions of lithotype and P- and S-wave velocities. Inversion results provide new insight to the spatial and petrophysical character of existing flow units and enable the efficient planning of primary and secondary hydrocarbon recovery operations.
Shape Factor in Fractured Reservoir Simulation
Authors: van Heel A. P. G. , Boerrigter P. M. 
Published: December 2007

Abstract
The shape-factor concept, originally introduced by Barenblatt in 1960, provides an elegant and powerful upscaling method for fractured reservoir simulation.
Since its introduction, many different values for the shape-factor have been proposed in the literature, among which the well-known Warren and Root, and Kazemi shape-factors. Different shape-factors can lead to totally different reservoir behaviour, so the selection of the appropriate shape-factor value is critical for accurate modelling.
The aim of this paper is to show that the selection of the appropriate shape-factor should not only depend on the "shape" and dimensions of matrix blocks, but should also take into consideration the character of the dominant underlying physical recovery mechanisms, convection or diffusion. We wil show that by taking into account the dominant physical recovery mechanism, the apparent discrepancies in the shape-factor values reported in the literature can be overcome.
We present concrete recommendations as to which shape-factor values to use in fractured reservoir simulations. We briefly review the shape-factors presented in the literature and argue that convection and diffusion-governed processes should be modelled using different shape-factors. We compare and contrast the predictions of different shape-factors for the case of steam-enhanced gravity drainage of viscous oil in a fractured reservoir.