bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effective Waterflood Management of a Giant Clastic Upper Burgan Reservoir Leads to Tripling of Production, Raudhatain Field, North Kuwait
Authors: Al-Hajeri Nasser , Chellappan Suresh , Al-Mufarrej Mishal 
Published: March 2019

Abstract
In the current and future scenario of increasing demand for hydrocarbons, Multi-Disciplinary Integrated Reservoir Management team is the key to achieve maximum production rates and ultimate recovery. In Raudhatain Upper Burgan reservoir production started in 1959 with initial reservoir pressure of 3850 psi. Decline in reservoir pressure with sustained rate of production indicated weak aquifer support and initiated water injection during the year 2001 with three flank injectors. Production rate was sustained at 30 to 35 MBOPD for long time and it was decided that to go the next level of production and to meet KOC's strategic production target.
Various alternative pressures – production plans were scrutinized by the multi-disciplinary team consists of Geologists, Reservoir Engineers, Petrophysicists and Petroleum Engineers and identified bottlenecks, constraints and action plan to address the problems and to accelerate the production. Some of the bottlenecks to accelerate the production were decreasing pressure, unavailability of required volume of water for injection, delay in commissioning of effluent water injection facility and low productivity of flank wells with viscous oil. The integrated Reservoir management team initiated number of projects to increase the productivity like Paradigm shift in drilling practice by way of drilling Horizontal, Multilateral wells and completing with ICD's for better production and injection sweep efficiency. Liquidated the sick wells with no potential in any other Reservoirs (Multiple Reservoirs) are identified for Horizontal Sidetracking to sweet spot areas. Decreasing Reservoir pressure and Voidage Replacement Ratio has been addressed by changing the water injection strategy and aligning the injectors in right areas.
The results were rewarding as the production rate doubled from a sustained level of 35 MBOPD to more than 70 MBOPD in a span of 3 to 4 years. The initiatives taken to convert the producers to injectors resulted in increased water injection volume and doubled the Voidage Replacement Ratio.
This paper presents the details of Integrated Reservoir Management team efforts and what are the initiatives and strategic actions taken by overcoming the current constraints to double its production. It discusses the effective Reservoir Management of a mature oil field to enhance and accelerate production.
Characterization of Iron Interaction with Viscoelastic Surfactant VES-Based Stimulation Fluid
Authors: Afra Salar , Samouei Hamidreza , Nasr-El-Din Hisham A. 
Published: March 2019

Abstract
Viscoelastic surfactant (VES) have been successfully applied as acid-diversion fluids. However, high temperature, interaction of VES and Fe(III), addition of alcohol-based additives, and chelating agents all interfere with the apparent viscosity of the VES-based acid and reduce its efficiency. In the present study, the interactions of Fe(III) with a new type of VES-based acid system, which can be applied effectively for diversion at high temperatures, were characterized.
Viscosity measurements were conducted on the VES-based acid in the presence of different concentrations of Fe(III) to characterize the rheological properties of the VES-based acid. The results showed that addition of Fe(III) in the concentration range of 2000 to 10000 ppm, lead to increase in the viscosity of the VES-based acid even at room temperature. Higher concentration of Fe(III) (more than 40000 ppm) lead to phase separation of VES out of the acid and formation of a brown gel-like material, which is considered as the main cause of formation damage by VES-based diversion fluids. IR spectroscopy was employed to understand the nature of the VES interactions with Fe(III) in live acid conditions. Also, UV-vis spectroscopy was conducted to determine stoichiometry of the reaction as well. The results show that interaction of amide part of the VES with Fe(III) that results in screening the repulsion forces between surfactant head groups and formation of wormlike micelles is the primary reason for increase in the viscosity.
To the best of authors' knowledge, although Formation damage caused by VES-based system due to iron contamination were reported previously both in the laboratory studies and field applications, the present paper is the first mechanistic attempt to characterize and understand the nature of a VES-based system interaction with Fe(III) as the driving force for the occurrence of reported formation damage. The findings of the present study can be utilized to further investigation of the effects of additives on the performance of VES-based systems.
Case Study Demonstrating the Estimation of Depth-Continuous Formation Anisotropy with Application to Geomechanics and Seismic Velocity Model Calibration
Authors: Hornby Brian , Wang Ruijia , Collins Mark , Kim JoonShik , Confer Rachel 
Published: March 2019

Abstract
This paper presents a case study in which new methods that use full-waveform sonic data are applied in an unconventional well setting to determine depth-dependent elastic anisotropy of formations penetrated by the well and estimate parameters of interest. The study objectives include the following: Estimate Thomsen's shear anisotropy parameter γ in an unconventional well that penetrates fast formationsUse rock physics and other approximations to further estimate a complete vertical transverse isotropic (VTI) elastic tensor at each depthCompare results with ground truth in terms of dynamic and static core measurementsUse these results to derive anisotropic geomechanical parameters for well completion and fracture treatment design and to compute upscaled seismic-equivalent elastic anisotropy for the calibration of anisotropic seismic velocity models
Formation speeds in this well were extremely fast, typical for unconventional shale reservoirs, which created a challenging environment for estimating VTI Thomsen's parameter γ because of the extreme sensitivity of the inversion to the accuracy of the borehole fluid slowness estimate. The key to the study's success was development and application of methods to invert for a depth-dependent mud slowness curve. This allowed for much more accurate inversion of the VTI parameter γ than the conventional method that uses a constant mud slowness value. In addition to enabling a more accurate inversion, it is observed that the mud slowness curve not only varied with depth [likely because of pressure/temperature (P/T) changes and possible settling] but also reflected quite different properties across a drilling fluid pill that was placed around the reservoir formations. This analysis provides an additional benefit for drilling engineers because the mud slowness curve tracks mud property changes in the well and can determine the actual location of the drilling fluid pill after placement and stabilization.
Additional work estimated the depth-continuous elastic tensor and geomechanics (anisotropic Poisson's ratios and Young's moduli necessary for computing horizontal stresses) for well completion and fracture treatment design. Seismic-scale properties were estimated using anisotropic Backus averaging for the calibration of the anisotropic seismic velocity model for prestack depth migration.
The Effect of Elevated H2S on Corrosion Behaviour of API 5L X65 Carbon Steel in High Partial Pressure CO2 Environments
Authors: Abas Ahmad Zaki , Mohammed Nor Azmi , Suhor Muhammad Firdaus , Ahmad Rusli Ahmad Mustaza 
Published: March 2019

Abstract
The corrosion behaviour of API 5L X65 carbon steel was investigated under high pressure carbon dioxide environments, containing elevated hydrogen sulfide, to simulate the condition of high carbon dioxide-containing natural gas subsea pipelines. It was systematically studied under high pressure carbon dioxide (120 bars) with a variation in other key parameters (hydrogen sulfide concentration and temperature). The corrosion rates were tested using High Pressure and High Temperature (HPHT) autoclave and measured using the techniques such as linear polarisation resistance (LPR), potentiodynamic sweep measurements, iron count, weight loss (WL) and electrochemical impedance spectroscopy (EIS). The surface morphology and the composition of the corrosion product layers were analysed using Infinite Focus Microscope (IFM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The results showed that in the CO2- saturated water phase, the addition of 2000 ppm hydrogen sulfide (H2S) instantaneously decreased the corrosion rate of carbon steel API 5L X65 at both 25°C and 80°C. The surface morphology and the composition of the corrosion product layers reveal the formation of mackinawite. The inhibitive effect of hydrogen sulfide at elevated concentration was observed and contributed to the significant reduction in corrosion. The effect on corrosion was despite the fact that water chemistry equilibrium was unchanged with the presence of elevated hydrogen sulfide.
DrillCAM Seismic System to Aid Geosteering and Drilling Optimization
Authors: Hemyari Emad , Bakulin Andrey , Silvestrov Ilya , Liu Yujin 
Published: March 2019

Abstract
As the number of new exploration and development wells continues to increase, guiding the bit while drilling in real time is becoming one of the most requested technologies. Seismic-while-drilling may enable accurate prediction of high-pressure zones, fractures and cavities, coring points, target depths, and geosteering in high-quality reservoir zones to optimize drilling decisions and reduce costs. A fully integrated real-time system to map and predict ahead of the bit and geosteer in high-quality reservoir zones is presented, showing application of seismic while drilling (SWD). We call this technology DrillCAM.
Recent enabling technological advances were made in wireless high-channel recording, signal enhancement and imaging algorithms, as well as high-performance computational resources that are easily deployable to the field. Such technological advances open a completely new set of possibilities for real-time drill bit guidance and navigation. One key enabler for DrillCAM is the use of wireless seismic receiver stations. Compared to conventional cabled geophones and cableless nodal systems, wireless receivers can provide real-time recording and transmission without the need for extra equipment for data retrieval, flexible receiver spacing and areal coverage. This, in turn, results in a flexible lightweight system for easy mobilization and ultralow power consumption for extended battery life.
We show a carefully designed field data acquisition experiment using the drill bit as a downhole seismic source and a large number of seismic receivers at the surface. The wireless receivers are arranged in flexible geometries that adapt to target bit depths. Using dedicated sensors, the bit signature (pilot signal) is recorded using high-frequency surface and downhole accelerometers. The system integrates surface seismic recordings and surface noise recordings with pilot signal recordings. The initial field experiment is conducted on a nearly vertical onshore well. This experiment demonstrates the feasibility of an integrated DrillCAM SWD system.
The paper presents the motivation, objectives, numerical studies, and first field test of a novel integrated real-time SWD system. Not only does such a system detect bit signals while drilling, it also validates these signals against other measured data and drilling activities.
Cost-Effective Sour Management in Mixed Production Systems
Authors: Chakraborty Soma , Lehrer Scott , Jani Jagrut , Ramachandran Sunder 
Published: March 2019

Abstract
Sour production from offshore and land-based wells causes hydrogen sulfide (H2S) release during downhole and topsides operations. Improper handling of H2S can lead to serious environmental and safety concerns as well as numerous corrosion and compliance issues. Consequently, H2S can add significantly to the total cost of well operations. The application of efficient H2S management technologies can reduce environmental and safety concerns, enable the use of lower-cost materials, and comply with H2S specifications. To remove H2S from mixed production applications, several chemistries are commonly used. The most common are triazines, glyoxal, and metal-based chemistries. Although each can be effective to a certain extent, these technologies have issues with efficiency or they can create serious side issues. The reaction of triazines with H2S in mixed production is highly inefficient and it creates scaling. Glyoxals suffer from poor efficiency, thermal instability, and corrosivity. The metal-based chemistries are the most efficient in mixed production, but in certain application regimes they can create serious solids and emulsion issues. These challenges can increase CAPEX and OPEX as well as lead to significant downtime and lost production. To overcome issues with currently used chemistries in mixed sour production, extensive research was conducted to identify chemistry that would efficiently remove H2S while minimizing negative side effects.
Systematic evaluation was performed for a series of chemistries to compare the scavenging efficiency, with a special emphasis on mixed production systems. Focus was also given on studying the associated side effects like emulsification tendency, scaling tendency, etc. to ensure the chemistry had no/minimal side effects seen by the more conventional chemistries. A high-throughput lab technique is presented that was designed to mimic scavenging tendency in sour mixed production environment. A continuous gas flow testing technique that helped study the reaction kinetics is also described.
Laboratory and pre-field results proved the efficacy of the new non-MEA, non-triazine chemistry in mitigating H2S in upstream, midstream and downstream applications while being especially efficient in mixed production systems. Laboratory testing proved the chemistry to be highly efficient compared to triazine in mixed production systems. Results also indicated the chemistry is non-emulsion forming and has very little scaling tendency. Testing conducted in the field demonstrated that the new chemistry cost-effectively removes H2S and meets the operator specifications.
The novel, non-triazine scavenger technology has significantly better performance than triazine, no emulsion concerns, acceptable HSE, non-corrosive effects, and less downstream concern than MEA triazine or metal-based scavengers. The new and differentiated chemistry reduces CAPEX and OPEX, drives productivity, improves reliability and reduces non-productive time.
Acoustic Characterisation of Phase Inversion in a Water-Oil System
Authors: Ahmed Yusuf , Arsalan Muhammad , Ahmed Talha , Noui-Mehidi Mohamed Nabil 
Published: March 2019

Abstract
The present paper is concerned with an experimental study of the acoustic signature of phase inversion in an oil-water mixture system. The system studied was used to correlate the process of phase inversion with the acoustic field generated during the two fluid mixing. The experimental results revealed that the relation between the acoustic fields produced by a water continuous dispersion and the phase inversion has a clear and different signature from an oil-continuous system using a batch mixing system. This dynamical characteristic of the phase inversion phenomenon could be of use in practical systems to detect phase inversion when it occurs based on the acoustic field measured in the subject process.
Deep Learning Method for Latent Space Analysis
Authors: Wallet Bradley , Ha Thang 
Published: March 2019

Abstract
Seismic attributes are a well-established method for highlighting subtle features buried in seismic data in order to improve interpretability and suitability for quantitative analysis. Seismic attributes are a critical enabling technology in such areas thin bed analysis, 3D geobody extraction, and seismic geomorphology. When it comes to seismic attributes, we often suffer from an "abundance of riches" as the high dimensionality of seismic attributes may cause great difficulty in accomplishing even simple tasks. Spectral decomposition, for instance, typically produces 10's and sometimes 100's of attributes. However, when it comes to visualization, for instance, we are limited to visualizing three or at most four attributes simultaneously.
My co-authors and I first proposed the use of latent space analysis to reduce the dimensionality of seismic attributes in 2009. At the time, we focused upon the use of non-linear methods such as self-organizing maps (SOM) and generative topological maps (GTM). Since then, many other researchers have significantly expanded the list of unsupervised methods as well as supervised learning. Additionally, latent space methods have been adopted in a number of commercial interpretation and visualization software packages.
In this paper, we introduce a novel deep learning-based approach to latent space analysis. This method is superior in that it is able to remove redundant information and focus upon capturing essential information rather than just focusing upon probability density functions or clusters in a high dimensional space. Furthermore, our method provides a quantitative way to assess the fit of the latent space to the original data.
We apply our method to a seismic data set from the Canterbury Basin, New Zealand. We examine the goodness of fit of our model by comparing the input data to what can be reproduced from the reduced dimensional data. We provide an interpretation based upon our method.
Streamlining and Automating Geological Requirements for Development Wells
Authors: Abouhenidi Malak , Fadul Reham , Tadamarry Faizuddin , Rahdi Yassir 
Published: March 2019

Abstract
Development wells are drilled for different purposes that varies based on the business needs. Some scenarios can be for flowing production, power water injector, gas, or to monitor the performance of a well. Coupled with the technology in wellbore drilling activity and the artifacts that are required for the workflow approval. Through evolving technology, the system captures every step of wellbore activity to address the business needs and streamline the approval process. Data fuels Industry Revolution (IR) 4.0 and effective data analytics is the prerequisite for successful implementation of digital enterprise applications.
Well approval is an in-house developed system embedded in Petrel application for reservoir characterization geologists. It standardizes well approval documents across the organization. The geologists may generate multiple well approval documents in case a change in the plan has occurred. Different scenarios require geologists to replace the plan that reflects the well approval document. Planning is the main pillar in the process of Well Approval, and automating the planning part simplifies the well approval process. The system automates the generation of three critical documents. First, Integrated Requirements (IRs), which consists of logging and threshold values for each hole section generates the reservoir amplitude impedance and porosity maps, and finally allows the geologist to capture seismic maps from 3D geological models. Second, Prognosis geological horizons details. Third, Location Evaluation. The backbone of this system is that it is integrated with different back-end systems such as corporate database, Petrel, Openwork and Geolog. In addition, geologists are not required to select the offset wells. The offset wells algorithm designates the wells for geologies based on specific criteria that is built in the system such as reservoir type and dynamic log selection. The system tackles both environments 2D and 3D based on the giving parameters such as facie. The system is able to detect the environment and prepare the documents accordingly.
Since the system is aligned with the business pattern for well approval process, it significantly improves the time required to create these documents from two to three (2-3) days to less than 1 hour (90%) and the data will be readily available through Real-Time Operations Center Knowledge System (also known as ROCKS) for further analysis and reporting.
First Successful Massive Hydraulic Fracturing Treatment Unlocks Reservoir Potential 4 Fold: Case Study from Tight Gas HPHT Field in Southern India
Authors: Sharma Vinit , Negi Anil 
Published: March 2019

Abstract
Hydrocarbon production from high-pressure/high-temperature (HPHT) unconventional and tight gas reservoirs is challenging the industry with its increasing complexities, changing geological and reservoir dynamics with deeper depth and temperature, stimulation techniques and the strategic cost investment. The southern basins of India offers a complete set of such variability, uncertainties and challenges that demand a more synergic approach and effort to produce. Field X is a deep HPHT tight gas field in the Krishna Godavri Basin with a permeability of &lt; 0.1 mD and a porosity of 10-12%.
Prior attempts of hydraulic fracturing were carried out in the field with limited success. Small volume jobs were pumped, yielding low-permeability coverage, with just an initial production gain and no sustainability on the gas production increase. Frac fluid recovery was an additional concern because of the tight nature of the reservoir.
This paper discusses the integration of log data, lab/fluid testing, production modelling, and fracture diagnostics that were used to design and optimize the massive hydraulic fracturing treatment. The technical methodology implemented during design, execution and evaluation phases for fracturing an HPHT tight gas well is discussed, including how the various risks were mitigated and the technical challenges were overcome. Finally, this paper elaborates the successful execution of the hydraulic fracturing treatment wherein ~332,000 lb of proppant were pumped–the largest in this field in a single stage. Initial production was enhanced by four times after the hydraulic fracturing. With the success of the hydraulic fracturing treatment execution strategy, fracturing operations were planned for the future field development wells to realize the true potential of the reservoir for increased and sustainable production.