bluuebunny/crossref_metadata_2025_split huggingface dataset:
X-Ray Micro-Computed Tomography Imaging for Coal Characterization
Authors: Ramandi Hamed Lamei , Armstrong Ryan T. , Mostaghimi Peyman , Saadatfar Mohammad , Pinczewsk W. Val 
Published: November 2015

Abstract
An Australian bituminous coal is imaged at high resolution of 16.1 μm with (wet) and without (dry) X-ray attenuating fluids present in the pore space using a large-field three-dimensional microfocus helical X-ray computed tomography (micro-CT) instrument. Scanning Electron Microscope (SEM) is conducted on slices of the specimen to visualize coal micro-features up to resolution of about 15 nm. Two- and three-dimensional image registration techniques are used to precisely overlay micro-CT tomograms of the core plug in dry and wet conditions and SEM images to yield detailed three-dimensional visualizations of the geometry and topology of the fracture systems in coal. SEM images are also used to produce a calibration curve based on the relationship between the micro-CT intensity values and the true apertures of fractures within coal. This eliminates the need for two sets of imaging. Advanced filtering algorithms are applied to segment the micro-CT image into four distinct phases: resolved fractures, sub-resolution pores and fractures, macerals, and minerals. The application of micro-CT in determination of relative age relationships between adjacent geological features is presented. The distribution of resolved aperture size within the coal sample is investigated and the variation of permeability and porosity in several sub-samples of the coal is plotted. The analysis suggests that coal permeability is independent of porosity and is likely affected by other petrophysical properties such as lithotype. To include the effects of mineral phase on coal properties, we remove the segmented mineral phase and merge it to the resolved fracture phase. This analysis affirms that minerals are deposited in highly connected regions.
DFN Model for Flow Simulation in Hydraulically Fractured Wells With Pre-Existing Natural Fractures Using Unstructured Quadrilateral Grids
Authors: Wang Keke , Peng Xiaolong , Du Zhimin , Haghighi Manouchehr , Sayyafzadeh Muhammad 
Published: November 2015

AbstractMultiphase flow simulation of hydraulically fractured wells with pre-existing natural fractures is a challenging task. Discrete fracture network (DFN) is an effective method to simulate a system of anisotropic fracture network. In DFN method unlike double porosity approach, fractures can be defined in different scales and in different apertures and directions such that all details of fractures will be included in the simulation. Also all the interactions and fluid flow in and between the fractures and within the matrix are modelled in a unified manner, using the same computational grid.We developed software based on DFN model in which both induced fractures and pre-existing natural fractures can be placed at any location and direction in the geological model. Then, quadrilateral unstructured grids are generated using Paving method. Quadrilateral grids are more efficient and more flexible than triangular grids such that the number of quadrilateral grids is reduced to half. A drawback of algorithm in this mesh generation process is that very small grids are generated in the intersection of fractures and in the ends of the fracture grids due to the size difference between the fracture and the matrix. In order to avoid severe time-step restrictions associated with small cells, an endpoint transformation method is used to replace the quadrilateral grids with the triangular grids at both ends of the fracture. As a result, the number of very small grids at the ends of fractures is notably decreased.In this paper, the results of two-phase flow simulation in a hydraulically fractured well with pre-existing natural fractures are presented. For solving the pressure and saturation equations in each grid, the inter region of quadrilateral mesh is taken as a control volume cell and the governing equations are solved using MPFA (Multi-Point Flux Approximation) technique which is designed to give a correct discretization of the flow equations for general non-orthogonal grids. Finally the results of our software are tested to verify its validity in theory, algorithm, and efficiency in calculation.
Optimizing Shale Resource Field Developments by Systems and Drilling and Completion Operations Modeling
Authors: Mitschanek M.. , Prohaska M.. , Thonhauser G.. 
Published: November 2015

Abstract
Efficiency is driving the cost for shale resource developments. Thus modeling of drilling and completion operations is key for increasing the pace of development in tough economic conditions. The objective is to develop an operational strategy that minimizes downtime on single pads, as well as to manage operations efficiently amongst multiple well pads.
As various options to move equipment are possible, simulation serves as viable tool to analyze the entire process. Field data build the basis for model formulation and calibration. Further, an operations, equipment and scheduling tool was developed to find solutions that allocate resources best possibly along the development.
What is found is that the industry has come quite a long way already in improving the operational sequence and the corresponding logistics of a development. It can be shown that batch drilling is a very successful way of improving efficiency when done correctly and when interdependencies of variables are targeted. To go beyond what is done today, the approach to de-bottleneck operations among all pads in one field of one operator has shown to decrease the time and cost to deliver even further. Through simulation, it is expected that the learning curve is increased and operators can benefit faster.
Detailed simulation of that aspect of a field development has often been neglected, but is applied on the regular basis in various other manufacturing industries world wide. A whole new generation of process modeling in the petroleum industry is started with this approach.
Predicting the Fracture System in Shah Structure in Onshore Abu Dhabi Using Analogue Modeling Approach
Authors: Sirat Manhal , Koyi Hemin 
Published: November 2015

Abstract
This paper aims at predicting the fracture system associated with the structural development of the Shah Structure in relation to a deep-seated basement fault. It discusses the possible geometry, frequency and fracturing modes, and the development mechanism of the fracture system revealed throughout a set of analog models, which emphasize the link between the basement fault and the sedimentary cover in a timely manner construction.
A 3D seismic data was used to construct a series of systematic scaled analogue models to reconstruct the structural evolution of Shah Anticline in association with an oblique sinistral strike-slip movement along basement fault, which induced both a strike slip movement in- and shortening of the cover sand layers. The deformation that was made by moving one of the basement plates in an oblique slip along the basement fault, resulted in an open anticline (box fold), which resembles the Shah Structure.
Analog modeling results presented here reveal that fractures associated with the asymmetric anticline have developed in different locations, and possessed different geometries and modes. As anticipated, both tensile and shear fractures have developed in different areas within both the crestal parts of Shah Structure and within its limbs. However, the asymmetrical geometry of the model-anticline is reflected in the fracture distribution, trend and frequency. The steeper limb of the anticline bear more developed fractures than the gently dipping limb. The asymmetry of the anticline is not equally well displayed by the post-erosional units above the unconformity "model Simsima", where a gentler anticline is displayed. Hence within this gentle part of the model-anticline the fracture pattern is less developed, less frequent and evenly distributed. Such vertical and horizontal asymmetries in fracture pattern (geometry, frequency and mode) seen in these analog models are expected to have in reality developed in the Shah Structure.
This new modeling approach has helped predicting the occurrence of different fracture system including geometry, frequency and fracture mode in different areas within Shah Structure. The predicted fractures have significant implications for exploration and field development plans of Shah Structure and those situated at the vicinity within Onshore Abu Dhabi.
Tackling Interbed Multiples with High Density Surveys, a Case Study Over the Rumaila Field
Authors: Ourabah Amine , Grimshaw Martin , Ernst Sabrina , Tough Kenneth 
Published: November 2015

Abstract
Interbed multiples have always presented a big challenge to interpreters of land seismic data, especially in Middle East basins where impedance contrasts can be quite high and appear at different levels of the subsurface. These interbed multiples not only affect the stack image, making the structural interpretation very uncertain, but also the pre-stack data, making the extraction of reliable AVO and azimuthal AVO attributes at the contaminated interfaces extremely difficult, if not impossible. Attempts at tackling these interbed multiples on conventional data using deconvolution techniques, 1D modelling or moveout-based methods are common practices (Berkhout & Verschuur, 1999; Jakubowicz 1998; Alvarez & Larne, 2004); while these methods can improve the stack image, their impact on the AVO response is often limited, especially on noisy land seismic. Recently, we are seeing more and more high density surveys being acquired thanks to new acquisition techniques such as simultaneous sourcing acquisition (Rozemond, 1996; Bouska, 2008; Howe et al., 2008); it has already been shown how this new generation of dataset can have a huge impact on the quality of the processing products and pre-stack attributes (Ourabah et al, 2014 & 2015). In this study, we demonstrate how we can also use high density dataset to remove interbed multiples by applying an innovative workflow to the Rumaila high density field trial dataset.
The Impact of Surface-Wave Separation on Seismic Survey Design
Authors: Ishiyama Tomohide , Blacquiere Gerrit 
Published: November 2015

Abstract
3-D seismic survey design should provide an acquisition geometry that enables imaging and amplitude-versus-offset applications of target reflectors with sufficient data quality under given economical and operational constraints. However, in land or shallow water environments, surface waves are often dominant in the seismic data. The effectiveness of surface-wave separation or removal significantly affects the quality of the final result. Therefore, the need for surface-wave separation imposes additional constraints on the acquisition geometry.
Recently, we proposed a method for surface-wave separation that can better deal with aliased seismic data than classic filtering methods such as in the wavenumber-frequency domain. This will impact survey design. Here, we investigate how the choice of a particular surface-wave separation affects the selection of survey parameters and the resulting data quality. To quantify the latter, we introduce a measure that represents the estimated signal-to-noise ratio between the desired subsurface signal and the surface waves that are deemed to be noise.
In a case study, we applied surface-wave separation and signal-to-noise ratio estimation to several data sets with different survey parameters. The spatial sampling intervals of the basic subset are the survey parameters that affect the performance of surface-wave separation methods the most. Finer spatial sampling will reduce aliasing and make surface-wave separation easier, resulting in better data quality until no further improvement is obtained. We observed this behaviour in our results as a main trend that levels off at increasingly denser sampling. With our new method, this trend curve lies at a considerably higher signal-to-noise ratio than with a classic filtering method. This means that we can obtain a much better data quality for given survey effort, or the same data quality as with a conventional method at lower cost.
IFL™ - A Novel Approach to the Rehabilitation of Sub-Sea Hydrocarbon Pipelines Using High Performance Solef PVDF Flexible Kevlar Reinforced Liners
Authors: Walters Robert A. 
Published: November 2015

PETRONAS Carigali (PCSB) is the owner and operator of an extensive network of sub-sea pipelines which are situated offshore from main land Malaysia, in the South China Seas. Many of these pipelines run from platform to platform and platform to onshore facilities over distances of between several hundred meters to several kilometers and in varying depths of water.
Severe internal corrosion, due in large part to Sulfate Reducing Bacteria (SRB) has caused some of the pipelines to have a drastically reduced life span which has historically resulted in the replacement of pipelines becoming necessary within a time period as short as four years. Historically, there has not been a viable methodology that could be utilized to install such a corrosion barrier within a sub-sea pipeline, thus the project for the design and development of InField Liner™ (IFL™) system was instigated and within three years brought to a highly successful conclusion incorporating the full rehabilitation of an 8" pipeline carrying Crude media and which was due to been decommissioned within six months had the installation not gone ahead. This particular pipeline is now fully anticipated to provide a further 25 years of operational use to PCSB.
Robert A. Walters, IFL™ Global Project Director and Chairman of Anticorrosion Protective Systems (APS), discusses the innovative InField Liner Technology, its offshore deployment within the PETRONAS pipeline network and the strategic plans for future global expansion. The company APS is a globally recognized pipeline rehabilitation specialist engineering and contracting company which is head-quartered in Dubai, U.A.E.
Reinvent Recruitment By Using Innovative Technologies
Authors: Kannankutty Manoj , Narayan Sumy Shankar 
Published: November 2015

Abstract
The objective of this paper is to discuss modern trends in technology to complement and improve recruitment cycle in the petroleum industry. The areas of focus are:
Sourcing and attracting talent using social media Mobile Apps Video screening interview
Social media
The largest social media networks are having a wider reach to audience around the world. Organization's presence in social media shall be very useful for social networking, references and recruitment.
Mobile apps
Mobile recruitment apps can help candidates view open positions, file their applications and receive notifications from recruiters using mobile devices like smartphones and tablets.
Video screening interview
Video screening interviews requires the candidate to record their video responses to a set of preset questions asked by the recruiter. Recording is done using a computer, laptop, tablets or mobile device without any break allowed during the interview.
Feasibility Study for An Unpiggable Subsea Pipeline
Authors: Stewart J. , Yablonskikh I. 
Published: November 2015

Abstract

Objective/Scope
Managing the long term integrity of a critical 10″ subsea crude oil pipeline is dependent on being able to use the correct inspection technologies, however, the current structure of the pipeline does not allow for any in-line inspections. Consequently managing the short term integrity of the pipeline becomes a priority until the pipeline is made piggable. This paper describes where and how to investigate along the pipeline to determine the current internal condition of the pipeline.

Methods/Procedures/Process
A desktop feasibility study was completed in order to determine the locations and the confidence in the use of an external ultrasonic scanning survey (auto-UT) to determine the short term integrity of the pipeline. This comprised the following: Technical identification of the points along the length of the pipeline that is most susceptible to internal corrosion.Confidence in evaluating condition of pipeline based on auto-UT
In addition a review of the current sacrificial anode protection of the pipeline was completed to ensure that any investigative works completed would not result in any external corrosion issues.

Results/Observations/Conclusions
For a product velocity of 0.28m/s, using the approach in NACE SP0208 (Appendix A), an inclination angle of 2° is critical for water accumulation. Review of the vertical profile of the pipeline indicated that there are nine sections exhibiting critical angle in excess of 2°. In addition 4 further sections of the pipeline are characterised by long inclines which could also contribute to water separation from the oil-water emulsion. Further consideration was given to sections of the pipeline where solid accumulation was possible, as this may aggravate internal corrosion. As the pipeline is practically straight in the horizontal plane (from bottom of riser) to the tee connection with a 20″ export pipeline, there are no additional pipeline fittings (dead legs) with the exception of a 10″ tap assembly to allow product into the 20″ pipeline.
Auto-UT provides highly accurate wall thickness measurement and a defect resolution from 1mm x 1mm. All measurements are recorded in millimetres and repeated inspections at the same location provide most accurate corrosion growth rates. The main concern with auto-UT is that it does not provide information on the condition of the whole pipeline, only for the area of pipeline covered by the auto-UT. This limitation has to be overcome with a correct choice of the locations to be inspected.

Novel/Additive Information
This paper describes the thought processes that must be undertaken when considering the short term integrity of an unpiggable pipeline: the likelihood and expected types of corrosion existing within,the likely locations, most susceptible for corrosion to occur andthe benefits of using various inspection technologies to determine both the short and long term integrity of the pipeline.
Non-contact Approach in Milling Operations for Well Intervention Operations
Authors: Gajdos Matus , Kocis Igor , Mostenicky Ivan , Kristofic Tomas , Taha Islam , Plichta Michal 
Published: November 2015

Abstract
The main objective of the paper is to present the possibility of non-contact approach based on electrical plasma in downhole milling or cutting operations. The features of this approach can be beneficial for a variety of Well Intervention applications characteristic for Middle East region. These applications include slot recovery, side-tracking, pipe recovery and several others.
The presented approach utilizes thermal electrical plasma capable to disintegrate a variety of materials (steel, cement, rock) with the same tool. Milling or cutting using this approach is based on a hybridized plasmachemical and thermochemical processes resulting fast metal degradation and removal in water steam environment. The main processes responsible for the rate and effectivity of steel/cement removal are oxidative processes as well as melting and evaporation. This non-contact approach utilizing coiled tubing (CT) technology brings also improved reliability by minimization of wear and tear of the tool itself.
Based on its features, the technology can bring the following benefits into Slot recovery application area: Multicasing milling in fewer trips100% rigless operation – Light Well Intervention Vessel offering flexible use and satisfying immediate needsGeneration of small swarf (no mechanical stuck, less viscous and cheaper fluids)Reduction of HSE-related risks due to reduced tripping and automated CT systemReduction of issues with fluid management due to simplified handling with milled materialShortening of the whole process due to its structural simplification
Similarly, the mentioned features can be used also for other potential applications including: Multi-lateral side-trackingPipe recovery of stuck BHARepair/replacement of damaged casingWellhead retrieval
Moreover, after development and modifications of the tool geometry, it can provide an efficient substitution of conventional junk/fish milling tools.
Log Technology Advances and Novel Data Analysis in Integrated Approach Unlock Full Potential of a Peculiar LRLC Reservoir Offshore Nigeria
Authors: Otevwemerhuere J. , Nwosu C. , Olare J. , Jefford Leigh , Parkins Steve , Cavalleri C. , Shrivastava C. , Espinosa H. , Mougang M. 
Published: November 2015

Abstract
Low resistivity low contrast (LRLC) reservoirs have been successfully produced for many years; however detection and detailed description of their properties and potential would remain a challenge in absence of an exhaustive formation evaluation program. Proper understanding of the geological evolution of such reservoirs to explain their distribution and variations in petrophysical properties is also vital.
Low resistivity pay reservoirs encountered in West Africa are often characterized by variation in resistivity values in vertical and horizontal directions due to fine grains and conductive layers within the coarse grained sands and clearly marked sand-shale laminations. This is accurately solved by tri-axial induction resistivity measurement in combination with high resolution measurements able to define any contributing layer level-by-level through robust anisotropic interpretation methods. However, heterogeneity, mixed clays effect, and complexity in rock texture require new technology and innovative interpretation models in multi-domain approach.
Advances in logging technologies, interpretation software, and analytical methodologies enable better and more refined reservoir models to be fashioned and tweaked as needed on a case-by-case basis. The case study analyzes log responses, implication of heterogeneity and mixed clays content on the generation of LRLC pay reservoirs in deltaic environment offshore Nigeria.
Precise application of advanced log measurements and integration of core data in a common workflow, built around the concepts of evolution of LRLC reservoirs lead to accurate pay quantification. Borehole image interpretation suggests that the low resistivity contrast is attributed to dispersed clays coating around the sand grains in the toe part of a delta front in major coarsening up and feeble fining up sequences. This is also confirmed by variations of elastic properties of the matrix.
Petrophysical logs recorded at high resolution correlate inferring the main causes of LRLC pay are clay content and distribution, and small grain sizes intermingled to the reservoir rock, hence resulting in low resistivity values in all directions and drastically increased irreducible water. The logs based model is confirmed by calibration to core analysis results. The confident results of the study confirm the power of collaboration between petrophysics, rock mechanics and geology in innovative interpretation workflows for enhanced reserves estimate and Producibility prediction in heterogeneous media.