bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility Study and Development Concepts for Barents Sea Oil Discoveries
Authors: Karimaie H. , Pourmohammadi S. , Nyrønning H. H. , Reeds J.
Published: March 2018

The purpose of this study is to provide a technical evaluation of the feasible development concepts for selected oil discoveries in the Barents Sea, named; Goliat, Johan Castberg, Alta, Gohta, and Wisting. The study is unique to the extent that includes consideration of all required elements for a field development project; subsurface conditions, reservoir engineering, production profiles, drilling schedule, subsea and topside facilities, infrastructure (existing and planned) and environmental concerns in the Barents Sea.

The selected method was based on high-level of facts, reservoir data, recoverable reserves, in place volumes and other available data, which all originates from public resources and literature. The collected data were systemized into our in-house developed profile generator tool. A predefined drilling schedule was implemented in the profile generator, and output was production rate and cumulative production.

Technical and commercial evaluation on three different development concept scenarios for the selected oil discoveries has been presented. Scenarios were defined based on using available and future planned infrastructure in the region. It has been shown that the distance between discoveries and the shoreline in the Barents Sea is relatively large, and resources are lower than what is commercially needed to evaluate as a stand-alone solution. The results of the study show that discoveries may be developed through a coupled reservoir solution.
Control and Analysis of Sustained Casing Pressure Caused by Cement Sealed Integrity Failure
Authors: Zhang Bo , Guan Zhichuan , Lu Nu , Hasan A. R. , Xu Shenqi , Zhang Zheng , Xu Boyue , Xu Yuqiang
Published: March 2018

Sustained casing pressure brings heavy routine maintenance and management workload, impedes stimulation treatments such as fracture and threatens safe production. This paper uses numerical model to analyze rising process of sustained casing pressure and study how cement sealed integrity is damaged, finally controlling sustained casing pressure by improving cement properties.

Cement sealed integrity collapse is one of the main reasons of sustained casing pressure, which distributes widely in high-pressure gas fields and gas storage reservoirs. First, numerical model is built according to volume consistency and mass conservation law to study rising process of sustained casing pressure. This model cam also clarify the relationship between sustained casing pressure and cement sealed integrity. And then a nonlinear equation set is established to study the mechanism of cement sealed integrity collapse. This equation set is based on Culon-Morper rule and stress-displacement continuity law. It can calculate micro annulus caused by wellbore pressure change. Lastly, a numerical model is built to predict the sustained casing pressure caused by micro annulus. Through this model, the influencing law of every factor is analyzed to find effective measures to mitigate sustained casing pressure and improve cement sealed integrity. The numerical calculation indicates that pressure rising period becomes shorter as cement micro annulus increases. Micro annulus happens when tensile force exceeds cement bonding strength. Optimizing the cement Poisson's ratio, and elasticity modulus can prevent micro annulus. Meanwhile, the casing internal pressure change should be controlled and cement bonding strength must be increased. It can inhibit micro annulus by using self-healing cement, casing sand adhesion and expansion casing, thus preventing sustained casing pressure. The optimization of cement top can permanently control sustained casing pressure.
Extending Virtual Metering to Provide Real Time Exception Based Analytics for Optimizing Well Management and Chemical Injection
Authors: Law Hiu Ying , Phua Pei Huey , Briers Jan , Kong Joanna
Published: March 2018

Shell Malaysia Upstream operations offshore Sabah and Sarawak in the South China Sea have been utilizing a data driven Virtual Flow Metering System to provide gas production estimates in real time for close to a decade. More recently, the analytics aspect of the system is helping to detect liquid loading in gas wells, support Exception Based Surveillance (EBS) and optimize chemical injection.

In the absence of multiphase flow meters, a Virtual Flow Metering System may be used for well by well production rate estimation. This has been implemented for the oil wells in a deepwater facility in Sabah, enabling onshore production support teams to monitor production from each well in real time. It is a cost effective approach to project delivery while enabling safe and reliable production. Production estimation by the Virtual Flow Metering System is derived from data driven models built using a series of well tests. These models are updated as often as well tests are performed and compared to the export meter to constantly validate the accuracy of the well-by-well production estimates.

For superior wells and reservoir management and to maintain asset integrity, exception based surveillance (EBS) is required. A large number of complex EBS requirements are being monitored in real time, using the signal processing and pattern detection capability of the Virtual Flow Metering System as the calculation engine. The intent of the EBS system is to alert onshore operations when a user defined operating limit is exceeded to facilitate actions to be taken in a timely manner. Some examples of EBS implementation are for sand detection and the quality of injected water and gas. Additionally, the EBS system is being used to detect liquid loading in mature Sarawak gas fields, leveraging on recent best practices reported elsewhere within the Group.

More recently, this Virtual Flow Metering System usage has been extended to provide Real Time corrosion inhibitor flow monitoring with the aim to track injection rates and keep injection on target, while minimizing excess chemical costs. Within days of the deployment of this real time surveillance tool, high injection alerts detected have resulted in significant savings. Over the same period, detection of low injection has allowed faster adjustments to increase injection and thus minimize corrosion effects to the pipelines.
Pipe-Soil Interaction at Engineered Lateral Buckle Touchdown Zones
Authors: Low Han Eng , Anderson Benjamin , Branby Fraser
Published: March 2018

Pipelines exposed to high temperature, high pressure (HTHP) may be susceptible to the phenomenon of lateral buckling. In some cases, engineered buckle initiators (such as sleepers and Zero Radius Bends) are introduced to initiate planned lateral buckles in the pipeline at specific locations in order to ensure the loading in each lateral buckle remain acceptable. Although this is a reliable method of buckle initiation this requires buckle intiator fabrication and installation which is expensive. Therefore, there are benefits to reduce the number of buckle initiators required for such a project.

The number and location of lateral buckle initiators are typically determined during the design phase based on simulations from lateral buckling response models using finite element analysis. The predicted response of these models is dependent on a number of factors including the initial pipeline out-of-straightness, operational conditions and pipeline-seabed interaction (and pipe-structure friction where applicable).

This paper demonstrates the importance of modelling the pipeline-seabed interaction in the buckle initiator touchdown zone appropriately through the presentation of a case study. The case study shows that by appropriately considering the specific pipeline-seabed interaction in the touchdown zone and/or the potential changes in pipeline span length over a buckle initiator, lower pipeline axial strains is predicted. This implies that the potential of reducing the number of buckle initiator structures required to control the pipeline lateral buckle during operation can be demonstrated, thereby potentially saving project cost.
Deepwater Northwest Borneo Geohazards Catalogue: Impact on Hydrocarbon Exploration and Development
Authors: Bong K. , Kamaruddin F. , Ismail S.
Published: March 2018

The seafloor and near-seafloor in northwest (NW) Borneo contains numerous challenges for the oil and gas industry. In recent geologic history (Miocene and Pliocene), NW Borneo has been very active. The collision of the Borneo plate with continental fragments in the South China Sea resulted in a deepwater fold and thrust belt. The fold and thrust belt is combined with both rapid sedimentation and an active hydrocarbon system resulting in significant geohazards. As part of the analysis, high-resolution seabed surveys, 3D seismic data, sediment cores, and well data were used to characterize these geohazards. Steep seafloor slopes, fault scarps, and fluid escape structures related to active, natural hydrocarbon escape features define the seafloor geomorphology, whilst gas, gas hydrates, overpressure, faulting, and over-consolidated sediment are common in near-seafloor strata in this region. These deepwater geohazards impact Shell's drilling and field development activities. Rigorous assessment of geohazards is critical for safe and efficient hydrocarbon exploration and development. The management of geohazards has been greatly improved by the Geohazards Catalogue, a web-based tool using My Maps (Shell's web mapping platform), and a new defined workflow to capture the full life cycle of geohazards data review and reporting. The catalogue has enabled geohazards specialists to focus on assessment, rather than searching for data. It is a valuable tool that increases effectiveness and efficiency of the geohazards assessment workflow in the organization.
Stochastic Approach on the Prediction of Deck Slamming Occurrence for Column-Stabilizing Platforms
Authors: Nam Hyunseung , Lim Dong-Hyun , Kim Yonghwan
Published: March 2018

Deck slamming phenomenon is one of the most critical factors in the design of column-stabilizing platforms. However, the prediction of its occurrence is not simple due to nonlinear effects in wave elevation and platform motion. In this paper, a stochastic approach is proposed to predict efficiently the probability of deck-slamming occurence for offshore structures. The present approach is based on the assumption of potential flow up to the second order and has four steps: representing relative wave elevation as two-term Volterra series, solving the eigenvalue problem, formulating the probability distribution of peaks applying the Hermite-moment method, and predicting the deck-slamming occurrence. Tension leg platform(TLP) and semi-submersible platform are considered as example models for the application of the present method, and the probability of deck slamming on various points is investigated for several ocean environmental conditions.
Unlocking Field Potential from High Mercury Wells: New Opportunities, Challenges and Solutions
Authors: Charoensawadpong P. , Chatwarodom P. , Manit P. , Atibodhi N. , Yongmanitchai M. , Hayook C. , Sujijantararat K. , Suwanvesh K.
Published: March 2018

The nature characteristic of the gas field in the Gulf of Thailand is having high CO2 and Mercury (Hg) content which pose significant operational challenges. Hg content ranges from 50 ppb to as high as 20,000 ppb, averagely at 3,000 ppb. More than half of those wells are required to be shut down under new sales condensate agreement which limit Hg content at 3000 ppb, resulting in a significant loss of opportunity in production. Since the production facility is already existed, it is challenging to maintain production and extend the field life by unlocking opportunities from those high Hg wells.

This paper will describe how to cope with Hg challenges to unlock potential from the field. Specifically, the short term and long term Hg handling and management plan, the operational challenges facing along the way and innovative yet simple solutions will be presented. With the successful Hg management project, the production from high Hg well is resumed. The long term solution by physical filtration method has achieved more than 80% of Hg removal efficiency. Hg filter operation together with the well integrated Hg management plan is the key to unlock field potential from high Hg wells.
Green Water Evaluation for FPSOs During Cyclones
Authors: Chen L. , Draper S. , Wolgamot H. , Taylor P. H. , Milne I. A.
Published: March 2018

A numerical tool is developed to predict the heading of a weather-vaning FPSO and the freeboard exceedance distribution around an FPSO for the assessment of greenwater overtopping. The heading prediction is compared with full-scale measurements from an operating FPSO for validation. The validated model is then applied to explore the behavior of FPSOs during the passage of tropical cyclones off the North West Shelf (NWS) of Australia. A synthetic database is used to represent tropical cyclone metocean conditions. The vessel is found to experience oblique wave attack frequently due to the misalignment in waves, current and wind. At some instances the vessel can be exposed to beam seas during the passage of a cyclone.

Analysis of freeboard exceedance indicates that three locations around the vessel are susceptible to increased risk of greenwater, these are the bow area, amidships and the stern of the vessel. It is also found that for locations around the bow and stern areas of the vessel, combinations of slightly smaller wave heights and shorter wave periods can lead to larger freeboard exceedance events. The freeboard exceedance statistics are sensitive to the vessel heading for the locations on the vessel where the exceedance event occurs. The incoming waves associated with extreme relative wave motion, i.e. freeboard exceedance, in directionally spread seas typical of tropical cyclones are identified. It is found that the maximum elevations of these incoming waves occur some time (on the order of one wave period) before the maximum freeboard exceedance for the seastates and vessel locations analysed due to the vessel motions.
Bearing Characteristics of Composite Conductor Structure: Deepwater Conductor Pipe with Suction Bucket Foundation
Authors: Changbin Kan , Jin Yang , Xiaocong Yu , Chao Fu , Nanding Hu , Lei Li , Yuming Yang , Can Zhang , Huanhuan Wang , Fatai Abimbola
Published: March 2018

In order to improve the vertical and lateral load bearing capacity of the drilling conductor, composite design of bucket foundation and drilling conductor was studied. The bearing behavior of composite conductor subjected to lateral and longitudinal external loads was investigated. In this paper, the finite element analysis was conducted by two methods, load loading and displacement loading. The bearing capacity and influencing factors of composite conductor were studied with consideration of contact surface models of composite structures and surrounding soil. The results show that the vertical bearing capacity increase with the depth increasement of the bucket foundation under the combined bearing effect of the bucket foundation and the conductor. Meanwhile, the depth of the embedded point of the composite conductor increases with the bending moment when subjected to lateral loads. When the bending moment is constant on the structure top, the lateral displacement of the structure increases with the increase of the vertical force, and the depth of the embedded point increases with the increase of the vertical force. The results also show that the change of the bending moment at the top of the composite conductor is more significant than that on the lateral displacement. The composite foundation can effectively reduce the displacement of the deepwater conductor and improve the lateral and vertical load bearing capacity of the structure. And also the research results can provide theoretical reference for further development and optimization of the deepwater composite conductor structure.
Well Design Assurance: An Independent Compliance Evaluation Scheme
Authors: Rios Renato , Johnstone Kris , Robb Dave , Walsh Frank , Davies Phil
Published: March 2018

Over the past decade, three mega-trends have created a groundswell of worldwide demand for government regulations on well construction activities. The first, hydrocarbon exploration and production in remote places and in reservoirs that are difficult to access and/or produce. The second, technology developments that have gradually redefined the boundaries of "conventional" in the different codes of practice. And the third, and perhaps the most important, is the renewed and urgent focus on environmental impact and sustainability, hastened by the rise of alternative sources of energy and the industry's serious and preventable incidents.

In addition, as organizations cut costs and make their best to navigate the low oil-price environment, there is an admitted concern of regulators (e.g. BSEE, HSE and PSA, 2017) that such optimization could result in squeezed margins in assets, operating systems and organizations. In response, regulators have moved toward standardization. Most operators have welcomed this approach, as criteria for approvals are clearer and equipment development costs decrease as a result of the shared functional specifications.

For well construction, one of the key industry initiatives to address the major system level risks relies on independent Well Design Verification/Assurance. It consist on applying disciplined engineering processes to examine a given design and analytically determine conformity with requirements (after API TR 17T8, 2015). The specified requirements include the mechanical integrity, life cycle service, and other survability requirements. This tool is an independent compliance assessment.

This paper describes the approach, major elements and high key considerations derived from accumulated experience of performing independent Well Design Verification for different clients and operators around the world.
Middle East First Introduction of MWD and RSS Systems Below Mud Motor Mitigates Vibrations in Harsh Drilling Environment and Delivers a Record Well in Egypt Western Desert Khalda Operations
Authors: Abdelsamad Hamdy , Muir Douglas , Ibrahim Abdelshafy , Mansour Mahmoud , Osman Ahmed , Rafik Ahmed , Remah Mostafa
Published: March 2018

Egypt Western Desert drilling fields have been known for harsh drilling environment, shock and vibrations conditions, interbedding and abrasive formations. Drilling assemblies have normally been suffering from excessive damages drilling through these conditions. Motorized rotary steerable drilling systems (RSS) were mostly considered the favored mechanism of drilling in this environment as they delivered higher drilling performance and mitigated vibration harmonics from transmitting higher up the string. Realtime shocks and vibrations data from directional tools was critical information to ensure safe and efficient drilling parameters and managing this harsh drilling environment without operating the equipment beyond its specifications.

In a recent western desert well, Khalda Petroleum Company (KPC) endorsed a new drilling strategy by modifying the conventional motorized rotary steerable drilling assembly from having only the RSS below the motor to having both the MWD and RSS tools below the motor. This modification was designed to enable KPC get closer measurements to bit with full transmission of all downhole data to surface to optimize the drilling parameters. The modification also aimed at increasing the bottom hole assembly (BHA) stability to prolong the run duration. To ensure reaching this goal, the design phase focused on two main directions. First, multiple finite element analysis modeling was implemented to ensure the optimum BHA stability and resistance to shocks and vibrations conditions. Second, KPC took needed considerations on the mud motor design, RSS operational procedures and MWD setup to ensure that these would fit properly in the new BHA design.

The strategy implemented has shown great success in delivering the section safely and with no incidents related to downhole drilling uncertainties and conditions. The section delivered the required directional profile with great precision and adherence. The new BHA actual data has shown high conformance to the modeled data and no shocks and vibrations conditions were encountered. The section was drilled in one run and was considered the longest and fastest directional run in its field. This has eventually lead to delivering this milestone section 3 days ahead of its planned timing.
Cost Effective Smart Cleaning Pigs Enabling High Frequency Pipeline Inspection
Authors: Jones Callum , Smith Richard
Published: March 2018

Pigging is necessary in both the maintenance and inspection of any pipeline, whether subsea or onshore. Operating in challenging environments and carrying potentially corrosive elements within the flow, a pipeline operator needs to be able to make decisions on integrity management based on relevant data.

In Line Inspection (ILI) tools are typically deployed every three to seven years and give an operator detailed data on the integrity of their pipeline. However, these tools can be complex to operate, disruptive to operations, expensive to run and sometimes not deployed often enough to give operators a key insight into their pipeline integrity before an incident occurs.

This paper will outline a new approach developed by a pioneering service company which enables operators to gather a significant volume of critical integrity data of their pipelines during regular cleaning and maintenance pig runs. The ability to inspect while cleaning reduces the requirement for mobilizing high value, MFL based ILI tools which additionally reduces personnel on board and improves operation economics.
An Effective Imaging Method which Combines Amplitude & Frequency Information in Seismic Sedimentology: RGB Blending
Authors: Du Jianpo , Ghulam Shabeer , Tan Seng Wah , Uli Deliza Aleesha
Published: March 2018

Seismic sedimentology has been widely used in Oil & Gas Exploration and Development industry. This is about the use of seismic data to study sedimentary rocks and the processes by which they form, and variety of techniques have been adopted in this emerging discipline, like Minus ninety degree rotation of seismic, Spectral Decomposition and Seismic inversion. The key objective is to obtain a high quality 2D image by Strata slice from these techniques. This 2D image contains lithological information from a certain geological time, and might help to delineate external reservoir architecture related to geomorphology and depositional model (such as channel, mouth bar and shoreface).

The conventional methods in Strata slice utilize either amplitude or frequency information. RGB blending, which divides the seismic into 3 cubes of different frequency band and blends together with Red, Green and Blue color, combines both amplitude and frequency information, thus RGB blending might provide a better image with rich information.

In this paper, the workflow of RGB blending contains 4 steps, the first step is to rotate the raw seismic by minus ninety degree, then the seismic amplitude could be used for lithological interpretation. The second step, based on the spectrum of the seismic, is to divide the seismic into 3 cubes of high, middle and low frequency band data through Marr wavelet transform. The summary of the 3 divided cubes should be very close to the seismic. In the third step, the amplitude of each three cubes will be converted into RGB color. The high, middle and low frequency band cube corresponds to Blue, Green and Red color respectively. The last step, blends the 3 color cubes together and do strata slice. The resultant 2D image will contain both amplitude and frequency information.

Seismic sedimentology study in one of producing field in Malaysia showed obvious applicability of RGB blending technique.
Transient Numerical Model for Narrow MPD Window
Authors: Fares Naceredine
Published: March 2018

In some wells, especially those drilled through fractured formations, the difference between the fracture pressure and the reservoir pressure becomes narrow. In these wells, maintaining ECD within the limits of fracture and reservoir pressures is a very challenging task, as many parameters have to be adjusted simultanusly to maintain the ECD.

When changing the pump rate and the backpressure to maintain the ECD within the MPD window, drilling fluid mass will change and an extra amount of fluid will be accumulated or released from the system as a result of the transient flow.

A numerical model is developed to enable the computation of the system mass change at any time due to change of the drilling parameters, which has to match the difference between the inflow and outflow. Any deviation will be interpreted as an external mass source (formation influx) or leak (fluid losses) and this can be used to enables early detection of losses or of formation influxes.
Advanced Analytics Solutions: Towards a Data Driven Organisation
Authors: Thajudeen S. Syed
Published: March 2018

This paper describes the PETRONAS' journey towards a data driven organization from the operational excellence perspective which includes the planning process, strategies, collaboration with multiple stakeholders, business case, technology selection, ICT infrastructure, management of change, capability building and many other challenges.

The right data needs to be identified and the data has to be clean to ensure analytics can be performed and the right decisions can be made laterally across functions and businesses to achieve optimum operational excellence.

Right at the equipment and process layer, the Internet of Things (IoT) provides a network of sensors and smart devices, with the advanced ability to make sense out of the data through the use of analytic tools and cloud services.

Access to readily available technical data from instrumentation connected to process and machinery equipment at both Upstream and Downstream facilities allows the Subject Matter Experts at centre to perform advanced analytics & provide solutions for optimization and troubleshooting. The advanced analytics will comprise of descriptive, diagnostic, predictive & prescriptive analytics. SME's will be able to establish effective monitoring and diagnostic strategies, including early warning of process and equipment deterioration or impending failures, and identify potential asset performance improvement areas.

Maintenance and reliability data from SAP also requires a clean up to allow Asset Performance Management to be performed effectively. Eventually this information will form the crux of Big Data Analytics where co relations between vast amounts of information will allow greater optimization to sweat the assets.

The mindset and work processes needs to be changed and competency in data science will be an important criterion for the future engineers. This transformation towards a data driven organization will require strong support and drive from the PETRONAS leadership team.

Starting as several proof of concepts, eventually, the program intends to encompass the whole PETRONAS group.
Southern Iraqi Oil Fields Drilling Problems Identification, Analysis, and Treatment
Authors: Saleh Ibrahim Abdul-Salam , Khalaf Alaa Hussein , Al-Jawad Mohammed Saleh
Published: March 2018

Multiple drilling problems are being faced continuously while drilling wells in the southern Iraqi oil fields. Many of which are handled poorly and inefficiently which yields longer non-productive time due to the lack of knowledge about the source of these problems. This study aims to investigate the Basra oil fields formations from Faris to Mishrif, diagnose the potential problems, and present the optimum treatment for each problem.

Gathering of field data and previous studies on the subject, in addition to the field experience of drilling supervisors were all the information bases of this study. Southern Iraqi oil fields were studied and analyzed carefully and widely starting with upper Faris formation (the first formation) to Mishrif formation (the last formation). The discussion of each formation is carried out comprehensively presenting their characteristics. All of the potential drilling problems that might be faced during the drilling operation are discussed while presenting their cause and source. A treatment plan for each problem is presented to ensure the most suitable solution.

As a result, the formations of southern Iraqi oil fields were studied vividly and a full characterization procedure was done including all the formations (from upper Faris to Mishrif formations). For each formation, the intensity and severity of the formation is explained by presenting all the problems that have occurred in offset wells or might occur due to potential causes that could yield the problem. The reason of each drilling problem and its origin is discussed. Multiple theories were discussed and proofed of why the drilling problems are found in these formations and their seriousness, the proof of these theories is presented in this study. For each problem, a treatment is concluded to ensure best practice, minimum time consumption, and least financial losses.

Southern Iraqi oil fields behold many drilling problems that are potentially dangerous unless acted upon with maximum care. In this study, a thorough discussion that explains the causes of these problems is presented, in addition to the most suitable treatment to handle each one.
Verifying Local Oil Reserves Using Multi-Well Pressure Pulse Code Testing
Authors: Sabzabadi Ali , Masoudi Rahim , Arsanti Dian , Aslanyan Irina , Garnyshev Marat , Minakhmetova Roza , Karantharath R. , Aslanyan Artur , Farakhova Rushaniya , Gulyaev Danila
Published: March 2018

The paper describes a practical case of using multi-well pressure Pulse-Code Testing (PCT) for assessment of inter-well connectivity and potential reserves for placement of new wells in off-shore environment. The study was based around two PCT cells (one calibration and one scanning) which were surveyed on the same platform within one month.

The calibration PCT cell was set around injectors in peripheral area to eliminate the uncertainty in reservoir saturation, and provided estimation of macroscopic reservoir permeability (ka) and macroscopic rock compressibility (cr) in cross-well intervals. The reservoir permeability was found to be in good correlation with core-calibrated log prediction, while rock compressibility turned out to be twice higher than expected. Additionally, the calibration PCT cell picked the seismic fault as being impermeable and provided accurate values of its proximity to the pulsing well and its extension in the north direction. The sealing nature of this fault explains poor aquifer support in the southwest of the field. The acquired information helped to improve matching of formation pressure in the dynamic model.

The scanning PCT cells identified the baffle in the southern part of the field, which was later interpreted as the bank failure of the meandering river flow. The study concluded that injection in river bedding is detrimental to uniform water flood pattern and should be avoided. The vertical sweep efficiency from PCT study was varying in different directions and helped to calibrate facies distribution and shale breaks. Some wells showed anomalous PCT behavior and were suspected of water production from thief zones, which was later picked by advanced production logging, based on spectral noise logs and temperature modelling.

The fine-grid 3D model was calibrated both on static and dynamic data including the newly acquired framework of PCT and advanced production logging. The analysis of the new model has located the areas of low mobility oil due to poor communication between injectors and producers in these areas. These areas were recommended for infill drilling as well as for rearranging the water injection pattern to improve the sweep and pressure support pattern. The production and water cut of the newly drilled horizontal well showed a good match with the calibrated model prediction.
Through-Drill Pipe Logging and Formation Sampling in Deviated and Risky Wells
Authors: Kulananpakdee K. , Chommali P. , Ngo Hien , Pinprayong V. , Kloos J. , Ryder I. , Villamizar C. , Baca Espinoza I.
Published: March 2018

Drilling wells in complex geological structures from offshore platforms, or onshore in areas with land access restrictions often creates complex S-shaped wells. In many such wells, high-angle doglegs cause problems with wireline key-seating, thus restricting reservoir access. When Logging While Drilling (LWD) data acquisition is not an option and Pipe-Conveyed Logging (PCL) is discarded because of its risky and time-consuming nature, many wells could end up without critical Formation evaluation data.

To overcome reservoir access challenges in the Sirikit Field in Thailand, a Through-Drill pipe Logging (TDL) technique has recently been introduced to complete formation evaluation. This method safely and effectively overcomes the complex well trajectories and associated wireline conveyance problems, such as key-seating. Slim 2.25" OD logging tools including Triple Combo (TC), Quad Combo (QC) and formation pressure tester and fluid sampler are deployed on wireline through open-ended drill pipe into open-hole without difficulties and with full well control maintained at all times.

A standard TDL operating procedure has been developed between wireline and drilling crews, allowing for safe and fast operations. The driller is able to have well control, with pipe being reciprocated regularly. Typically the drill pipe is run with a reamer shoe to allow borehole cleanout operations in the same run. The TDL deployement method is now a key component in the standard decision tree for data acquisition strategy in Sirikit Field and it has been successfully introduced in the Sirikit Field in May 2016. Since then, a total of 59 runs have been performed in 31 wells where wireline reservoir access problems were encountered, saving an estimated 1,240 hours of combined rig time not counting any potential wireline fishing jobs that would likely have occurred. A near 100% success rate is maintained, measured by reaching well TD and acquiring all desired wireline data. Petro physicist and geologists are no longer left without the crucial formation evaluation data they require for successful reservoir management.

This paper present a case study that clearly demonstrates that the TDL deployment technique can be very effective in providing safe and efficient wireline access to reservoir sections in S-shaped wells with risky wellbore conditions, where high-angle doglegs and key-seating would otherwise have restricted the ability to obtain Formation evaluation log data and fluid samples.
Managing Nitrogen Hazards on Floating LNG
Authors: Wong R. Harris , Kayat Z. , Loh I. , Rashid E. Abdul , Bacha N.A. Sikandar
Published: March 2018

The purpose of this paper is to share the challenges and engineering solutions in managing risk of using nitrogen as the refrigerant in the LNG (Liquefied Natural Gas) liquefaction process on a Floating LNG (FLNG). In December 2016, the first FLNG started to produce LNG 130 km offshore using Nitrogen Liquefaction Technology, which is also the first in the world. Multi-Component Refrigerant (MCR) is commonly used to liquefy natural gas worldwide in the LNG plants. However, the Nitrogen Liquefaction Technology has been selected in view of its inherently safer non-flammable non-corrosive property, simplified process and reduced refrigerant handling and storage onboard. As compared to MCR, the flammable hazard on the FLNG is reduced by adopting nitrogen as refrigerant. Nevertheless, during the course of engineering design, other risk that could potentially be posed by nitrogen was identified. The main concern is the brittle fracture and anoxia risk in the event of cryogenic nitrogen loss of containment. This leads to engineering challenges in terms of the process containment, structural impact, ability to detect, safe disposal and drain and lifesaving appliances, etc. This sharing can be the pioneer reference for other FLNG designs in particular the refrigerant system, the relevant risk management and the engineering solutions.
Heavy metal bioaccumulation in commercial Lethrinidae fish species in Mauritius
Authors: Saulick Bhanoo , Bhoyroo Vishwakalyan , Nazurally Nadeem , Lalljee Bhanooduth
Published: March 2018

Concentrations of heavy metals arsenic, cadmium, lead and mercury and trace elements chromium, copper, nickel and zinc were tested in the muscle tissue of four commercial edible lethrinids fish species from different region of Mauritius. Sky emperor (Lethrinus mahsena) was collected from coastal regions as well as offshore regions (banks) for this study. Blackspot emperor (Lethrinus harak) and spangled emperor (Lethrinus nebulosus) were also studied for their popularity in the fish market. Condition factor was calculated for each fish and the highest value obtained was in Lethrinus mahsena collected from offshore regions (2.598 cm/g). Flame atomic absorption spectrometry was used to analyse copper, nickel and zinc while, graphite furnace technique was used for cadmium, chromium and lead. Mercury levels were evaluated with the cold vapour technique and arsenic with the thermal hydride cell. The level of lead, mercury, copper, nickel and zinc ranged from 0.0011-0.0024 mg/L, 0.0016-0.0036 mg/L, 0.080-0.389 mg/L, 0.566-1.192 mg/L and 0.219-0.422 respectively in wet weight. Interspecies variations in levels of heavy metals and trace elements were observed for nickel and no significant variations occurred for mercury, lead and zinc. Concentrations of heavy metals and trace elements were all within the permissible level except for nickel. As per this study, the Food Act 1998 of Mauritius must be reviewed in order to incorporate the Maximum Permissible Level for nickel.
Current trends in the management of trapeziometacarpal arthritis
Authors: Eltorai Adam E.M. , Han Alex
Published: March 2018

The purpose of this update is to report on a variety of topics related to trapeziometacarpal arthritis that have been recently investigated. The keyword trapeziometacarpal arthritis was utilized to query the PubMed database of the U.S. National Library of Medicine. From the resulting list, papers published from the beginning of April 2014 through the beginning of April 2017 were reviewed. The forty-five studies identified are reviewed here and referenced.
Primary leiomyosarcoma of the distal fibula: A case report and review of the literature
Authors: Hanafy Marwan , Schwonzen Martin , Kuhnen Cornelius , Schley Bernhard , Wilke Axel
Published: March 2018

We describe a primary leiomyosarcoma of bone located in the distal fibula in a 67- year-old man. Plain radiographs and computer tomography scan revealed a lytic destructive lesion in the distal metaepiphyseal region of the left fibula with little involvement of the surrounding soft tissues. The lesion was composed of proliferating spindle-shaped cells with very slim cytoplasm and narrow oval cigar shaped nuclei. Immunohistochemistry studies demonstrated a strong positivity for actin and desmin, and weak positivity for caldesmon.
Open fires in Greenland: an unusual event and its impact on the albedo of the Greenland Ice Sheet
Authors: Evangeliou Nikolaos , Kylling Arve , Eckhardt Sabine , Myroniuk Viktor , Stebel Kerstin , Paugam Ronan , Zibtsev Sergiy , Stohl Andreas
Published: March 2018

Abstract. Highly unusual open fires burned in Western Greenland between 31 July and 21 August 2017, after a period of warm, dry and sunny weather. The fires burned on peat lands that became vulnerable to fires by permafrost thawing. We used several satellite data sets to estimate that the total area burned was about 2345 hectares. Based on assumptions of typical burn depths and BC emission factors for peat fires, we estimate that the fires consumed a fuel amount of about 117 kt C and produced BC emissions of about 23.5 t. We used the Lagrangian particle dispersion model to simulate the atmospheric BC transport and deposition. We find that the smoke plumes were often pushed towards the Greenland Ice Sheet by westerly winds and thus a large fraction of the BC emissions (7 t or 30 %) was deposited on snow or ice covered surfaces. The calculated BC deposition was small compared to BC deposition from global sources, but not entirely negligible. Analysis of aerosol optical depth data from three sites in Western Greenland in August 2017 showed strong influence of forest fire plumes from Canada, but little impact of the Greenland fires. Nevertheless, CALIOP lidar data showed that our model captured very effectively the presence and structure of the plume from the Greenland fires. The albedo changes and instantaneous surface radiative forcing in Greenland due to the fire BC emissions were estimated with the SNICAR model and the uvspec model from the libRadtran radiative transfer software package. We estimate that the maximum albedo change due to the BC deposition was about 0.006, too small to be measured by satellites or other means. The average instantaneous surface radiative forcing over Greenland at noon on 31 August was 0.03 W m−2, with locally occurring maximum values of 0.63 W m−2. The average value is at least an order of magnitude smaller than the radiative forcing due to BC from other sources. Overall, the fires burning in Greenland in summer of 2017 had little impact on BC deposition on the Greenland Ice Sheet, causing almost negligible extra radiative forcing. This was due to the – in a global context – still rather small size of the fires. However, the very large fraction of the BC emissions deposited on the Greenland Ice Sheet makes these fires very efficient climate forcers on a per unit emission basis. If the expected further warming of Greenland produces much larger fires in the future, this could indeed cause substantial albedo changes and thus lead to accelerated melting of the Greenland Ice Sheet. The fires burning in 2017 may be a harbinger of such future changes.
Non-native invasive species as paradoxical ecosystem services in urban conservation education
Authors: Battisti Corrado , Fanelli Giuliano , Bertolino Sandro , Luiselli Luca , Amori Giovanni , Gippoliti Spartaco
Published: March 2018

Abstract. Many practices have been proposed in conservation education to facilitate
a re-connection between nature and the young digital generation in
anthropized contexts. In this paper we suggest that, at least in some
specific circumstances (urban and suburban areas), non-native invasive
species may have a paradoxical and positive impact in conservation education
strategies, playing a role as an experiential tool, which represents a
cultural ecosystem service, i.e. an ecosystem service that produces cultural
benefits by improving pro-environmental behaviours in young people.
“Glocalized” Utopia, Community-Building, and the Limits of Imagination
Authors: Schiffer Steven Jay
Published: March 2018

What happens when intentional communities break from lingering associations with socialism in favor of supposedly more savvy or self-conscious forms of utopianism? Attempts to grapple with globalizing neoliberalism, giving rise to “glocalized” utopia, highlight how ill-fitting the categorization of intentional communities as programmatic utopias is. Engagements with “everyday” utopianism in the face of an agency- and imagination-limiting globalizing neoliberalism suggest that in contemporary lived utopianism the everyday has become the program; contemporary utopianism in some North American intentional communities is defined by concerns for “raising consciousness” and “creating space”—efforts symbolic of the blending of programmatic and everyday utopianism. This article offers an ethnographic case study of this blended, glocalized form of utopianism, drawing on fieldwork to investigate how ecovillagers in the Yarrow Ecovillage make “everyday” life a site of self-conscious social reform. It then argues that glocalized utopia emerges when community aspirations for social reform confront neoliberal “recuperative capitalism.”
Propuesta Simbiótica Natural-Cultural en Territorio Mapuche de Arauco
Authors: López Mario , Valenzuela Andrea , Carrasco Claudio
Published: March 2018

Esta investigación evalúa las formas de ocupación en el territorio mapuche y sus procesos de transformación en la comuna de Arauco. La hipótesis plantea que se ha perdido la relación simbiótica natural-cultural entre el mapuche y su entorno. La metodología consistió en la caracterización del paisaje de manera cualitativa y cuantitativa en el contexto del grupo indígena, partiendo con 39 indicadores de primera generación, asignados y creados a la medida. Luego se formaron 8 componentes principales o indicadores de segunda generación, representando un área de análisis multidimensional, para luego ser agrupados nuevamente y formar un indicador de tercera generación o Índice de Sustentabilidad del Paisaje de Arauco (ISPA). Cada indicador fue jerarquizado dentro de su componente por medio del Proceso de Análisis Jerárquico (PAJ), resultando una cifra única para entender el estado de sustentabilidad de la comuna analizada en 4 períodos de tiempo (Siglo XVI, Siglo XVII, 1960 y

2016). El análisis de la información evidencia una pérdida de la condición simbiótica natural-cultural. Por último, se realiza la propuesta de una imagen objetivo, llevada a cabo con una sistematización de los resultados y la percepción actual de las comunidades mapuches por medio de talleres y entrevistas

donde se graficó el esquema de una unidad comunitaria mínima para un territorio cuantificado por hectáreas y porcentajes promediados según los resultados. La propuesta se enfoca en la visión y recuperación del territorio para lograr la Sustentabilidad del Paisaje Mapuche.
Centro de visitantes para la interpretación y exploración del Paisaje Cultural Pewenche.
Authors: Díaz Toledo Yanko
Published: March 2018

El Centro de visitantes en Cauñicú busca ser un hito en este núcleo cultural activo, dando respuesta a su inminente extinción patrimonial por la amenaza de la primera central de paso en el valle del Queuco a través de la puesta en valor del Paisaje Cultural Pewenche. Un sendero que acoge y protege el espacio más íntimo de la cultura Pewenche para la comunidad y una arquitectura que reinterpreta la espacialidad de la misma pretenden producir un espacio diáfano para la cultura, promoviendo el puntapié inicial de un debate inexcusable en nuestro país.