bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arctic Pipeline Leak Detection using Fiber Optic Cable Distributed Sensing Systems
Authors: Thodi P. , Paulin M. , Forster L. , Burke Julie , Lanan G. 
Published: June 2014

Abstract
Multiple offshore Arctic fields have been developed over the past three decades and the world demand for oil and gas will continue to drive hydrocarbon development in Arctic and sub-Arctic environments. Arctic pipelines are used for the safe and economic transportation of hydrocarbons. While pipelines are designed not to leak, excessive strains due to the effects of ice gouging, strudel scour, frost heave and permafrost thaw settlement along with other loading and failure mechanisms (i.e. corrosion, third party damage) could result in a leak. Failure to detect leaks in a timely manner could have severe safety, environmental, and economic impacts. Large leaks can easily be detected, but small chronic leaks may go undetected for a period of time, especially when pipelines are buried in remote locations or under seasonal ice cover.
First, this paper reviews existing Leak Detection System (LDS) technologies for their potential use on Arctic and sub-Arctic pipelines. The technology evaluation based on regulatory requirements and functional criteria suggests that Fiber Optic Cable (FOC) distributed sensing systems have a high potential to be used on Arctic pipelines. Distributed sensing FOC can be used to detect and locate leakages. Pipeline leakage would generate a local change in temperature. These thermal anomalies can be captured by FOC Distributed Temperature Sensing (DTS) systems with good spatial and temporal resolution. Similarly, the acoustic signature generated by leaking fluid can be detected using FOC Distributed Acoustic Sensing (DAS) systems. Inelastic Brillouin and Raman backscattering principles are used for measuring temperature in DTS, whereas the Rayleigh backscattering principle is used for measuring acoustics in DAS. This paper presents information on applicable regulations, operating principles, optical budgets, system integration, sensor positioning, installation and maintenance assessment, technology status, risk analysis using Failure Mode, Effects and Criticality Analysis (FMECA) and field implementation challenges.
Spectral Fluorescence/Reflectance Optical Sensor Systems for Arctic Oil Spill Detection and Mapping
Authors: Mooradian Greg , Richter Dean , Marttila E.J. , Solonenko Michael , Saade Edward 
Published: June 2014

Abstract
In the rapidly expanding field of oil exploration and production, there is an emerging requirement to reliably detect, characterize and geospatially map oil spills in ice-covered waters during both summer and winter months in the Arctic. This paper postulates two possible platform-based sensor architectures and examines predicted performance for the following:an airborne, high-search-rate Spectral Fluorescence/Reflectance Lidar (SF/RL) that has the potential to detect and geolocate oil beneath the Arctic ice as well as accurately measures ice thickness andan autonomous underwater vehicle (AUV)-borne sensor that can operate between the seafloor and the base of the ice utilizing an active optical spectral detection and discrimination sensor for oil trapped under the ice, settling on the seafloor and drifting in the water column. Search rates for an aircraft at 2,000 ft and 125 kts through 4 inches of snow and 8 feet of ice with nominal Lidar system parameters is predicted to be 336 km2/hr (1.5 km swath width and 20 m spatial sampling). The AUV-borne sensor would be composed of a compact SF/RL payload that conically scans ± 50° from nadir at a nominal oil detection depth of 75 ft.
Ice Gouging and Its Effect on Pipelines
Authors: Liferov Pavel , Nes Hroar , Asklund Joakim , Shkhinek Karl , Jilenkov Alexander 
Published: June 2014

Abstract
The objective of this paper is to demonstrate how modelling can be used to account for the inherent correlations while assessing the pipe response to ice gouging – and thus narrow down the uncertainties associated with the pipeline design process.
A custom-developed numerical model of ice gouging has been developed and exercised to better understand how the environmental conditions affect the gouging process. Further, numerical simulations of the keel-soil-pipe interaction have been performed, relating to the input and output of the ice gouging model.
The ice gouging simulations quantitatively demonstrated the effect of the governing parameters on the gouge depth. Geotechnical conditions are very important as the main source of resistance against the driving force from ice, making a noticeable difference in the gouge depth. Force balance is also important, in particular how the vertical forces are generated or/and limited by natural phenomena such as the shape of an ice feature, seabed topography and tides. The effect of the driving force and the keel resistance limits have not been dealt with within the scope of the present study.
The ice gouging simulations demonstrated that ridges with steeper rake angles result in deeper gouges. Similar gouge depths have been attained irrespective of the path – via water level changes or via seabed slope - as long as the driving force was available. The keel-soil-pipe simulations demonstrated that increasing the rake angle results in lower pipe response. Deeper gouges give larger effect at the same clearance between the top of the pipe and the gouge bottom.
Considering the performed simulations jointly, it can be concluded that selecting the n-year gouge depth implicitly sets the conditions for assessing the variability in the additional governing parameters. This is mainly applicable to the keel's rake angle as the factor having the strongest correlation with the gouge depth, keeping other parameters unchanged. Appreciating the correlation above and its effect on the n-year pipeline load effect can prevent possibly overly-conservative parameter combinations.
It is argued that steeper keels have the highest potential to produce deepest (extreme) gouges. For these conditions, the extreme gouge load effect seems to be acceptable as long as there is a gap between the pipe and the ice keel and the pipe wall thickness is relatively large. Thus, the pipeline design against ice gouging load effects is likely to be governed by the maximum gouge depth, as the gap itself is found to define a sharp limit between an acceptable and an unacceptable design condition. In turn, this sets high requirements to reliable determination of the gouge depth.
Arctic Offshore Pipeline Design and Installation Challenges
Authors: Paulin Mike 
Published: June 2014

Abstract
With the oil industry's continued quest for oil and gas in frontier offshore locations, several developments have taken place in regions characterized by seasonal ice cover including the US Beaufort, North Caspian, and Sakhalin Island. In these projects, pipeline transportation systems have been used, which are a cost effective, safe and reliable mode of hydrocarbon transport to shore. Ice gouging is one of the key design issues that affect engineering considerations with respect to strain based design, target burial depth requirements, cost, and safety.
It is generally accepted that offshore pipelines in ice environments will need to be trenched and backfilled for protection. Burial depths can be greater than those that might normally be required for pipelines in temperate climates. Burial depth requirements will be a function of the design ice gouge depth (to prevent interaction between the ice and pipe) and an acceptable level of subgouge deformation beneath a gouging ice keel (which potentially strains the pipeline). There still exists uncertainty on the magnitude and extent of subgouge soil deformations due to ice gouging and the importance of sediment transport mechanisms for biasing gouge statistics.
Other challenges that must be considered include strudel and hydrodrnamic scour, thaw settlement and frost heave, and upheaval buckling. These considerations may also influence burial depth requirements.
Control of Bottomhole Pressure in Managed Pressure Drilling using IMC Controller
Authors: Nandan Anirudh , Imtiaz Syed , Butt Stephen 
Published: June 2014

Abstract
In this paper we present a simple proportional integral (PI) with internal model controller (IMC) tuning for kick/loss rejection for managed pressure drilling (MPD) process. Arctic regions are very fragile and hence precaution must be taken to avoid any blow out. MPD is a promising technology for well control. Several complex controllers are available in the literature for controlling MPD but design and implementation of such controllers require the knowledge of advanced controls. It would be beneficial to check the suitability of simple controllers for the control of MPD. We propose a switching PI controller with IMC tuning. In order to synthesis the controller the process between the bottomhole pressure and choke opening was identified. It was observed that the process was highly nonlinear for lower choke openings and hence two separate cases of choke openings were considered for controller synthesis. The synthesized controller was used to reject a kick of 100 lpm and it was observed that performance of the controller was reasonable. We also show that the controller will be able to track the setpoint robustly at different choke openings. The proposed controller requires minimal human interference and it is very simple to implement. We demonstrate that complex advanced controllers will be beneficial from a technical point of view and to meet tough conditions, nevertheless simple controllers can also deliver a reasonable performance.
Methodology for Combined Local and Global Ice Pressure Estimation based on a Probabilistic Model of High Pressure Zone Behavior Derived from Field Data
Authors: Taylor R.S. , Richard M. 
Published: June 2014

Abstract
As our understanding of the failure processes and mechanics associated with individual hpz behavior advances, new models are needed to link hpz behavior with local and global pressures for full-scale interactions. This paper is focused on the development of a probabilistic compressive ice load model for thin first-year sea ice based on statistical descriptions of high pressure zones (hpzs) derived from the analysis of tactile sensor data collected during the Japan Ocean Industries Association (JOIA) medium-scale field indentation test program. The aim of this work is to provide a probabilistic model of hpz behavior that simulates observed local and global pressures and associated scale effects, particularly for interactions involving thin first-year sea ice. Probabilistic descriptions of high pressure zones based on field measurements have been extracted and are incorporated into a model for linking hpzs with methodology for ice pressure estimation. A comparison with local and global pressure design curves generated using methodology provided by ISO 19906 is included.
Comprehensive Adjustment Techniques Based on Detailed Oil Distribution Enhance Oil Recovery at Mature Offshore Field
Authors: Li Tingli , Wang Yunxian , Liao Xinwu , Zhao Chunming , Yang Qinghong , Su Yan chun , yong Hu , Wei Qin , Xu Yuxia , Bie Xuwei , chao Liu , Su Jinchang , Zhang Yunlai , rong Fu , Yu Dengfei , Wei Zhang 
Published: June 2014

AbstractQin Huang Dao 32–6 (QHD32–6) oil field located at Bohai Bay of China is a large heavy oil (74–260mPa.s) field with flat structure, multi-pay zone, complex oil and water contact system discovered by CNOOC (Fig. 1). The development plan is drilling vertical wells to penetrate multi zones with large well space (350-400m) in 3 blocks (North, South, and West). Due to comingle production pattern and quickly coning of the bottom water, the wells became mainly water producer and faced to be shut-down after a short period of the first oil.Measurement like water zone isolation and water injection optimization has been conducted to improve the production for short time. However, it is still not feasible in a long run to enhance oil recovery based on the research of water sweeping condition and remaining oil distribution. We faced a number of challenges, such as low oil production (35m3/d), high water cut of the field(86.6%) and low recovery factor(11.3%). A quick implementation of field comprehensive adjustment plan is needed to arrest the quickly water coning and fast production decline. While designing, a workflow integrating geological, well log, seismic and dynamic production data was developed to optimize the oilfield recovery factor.Following the workflow, we started with detailed reservoir description of sandbodies and systematically analyzed the remaining oil distribution mode. Then the comprehensive adjustment plan focus on develop from separate zones was carried out and the first batch of infill horizontal pilots was implemented. The responses from pilots were very positive resulting in better oil productivity (64m3/d) and longer low water-cut period.Finally, the comprehensive adjustment plan put forward 101 new infill wells and converted some part of old vertical wells to inject water for separate zones production, which resulting in 10% recovery factor enhancement. The oil recovery rate is raised from 0.8% to 1.7%. Our experiences showed that such comprehensive adjustment techniques based on detailed oil distribution is crucial to achieve better water-flooding development efficiency for offshore reservoir.
Post-installed Mudmat
Authors: Fontaine Emmanuel , Dilosquer Steven 
Published: June 2014

Abstract
The paper presents a new subsea structure foundation concept and installation method, called the post-installed mudmat. With this new method, the thermal expansions and displacements of HP/HT flowlines are no longer limiting criteria for the subsea structures. It is applicable to the pipeline end termination (PLET), either first end or second end, and In-Line Tee structure to be laid in any mode (S, J or Reel lay). Combined with Subsea 7 experience of installing structure in all modes, the study is based on computer works to verify the installation sequence, the pipeline integrity and the geotechnical strength.
The post-installed mudmat concept is applicable to the projects where the pipe laying method includes structures. In the present application, the pipeline is laid in standard S (also applicable to J or Reel lay) mode with a piping module, including valve and connectors, going through the vessel tensioners and stinger also called firing line. Generally two mudmat wings are added before reaching the stinger and then unfolded subsea. In the new method, a purposely designed mudmat and associated devices is post-installed at sea-bed level on top of a previously laid simple pipeline and module. The specific mudmat guiding and securing device allows the pipe module leveling and weight transfer before the mudmat fulfills its foundation functionality.
Comprehensive computer simulations have been performed to verify the laying of pipe module and the new post-installed mudmat on the sea-bed. Calculations confirm the integrity of the pipeline at anchor point to the mudmat after installation. Geotechnical simulations also verify the piping module temporary bearing and the final foundation capacity and settlement. The post-installed mudmat design brings a significant contribution to the pipeline laying method. The mudmat size is no longer a limiting parameter for its integration in the main line. Compared to its opposite design, the pre-installed mudmat, it is not impacted by the installation tolerances which would make it larger and longer. It can also be fixed, sliding or fitted with rails to accommodate the pipeline thermal expansion without significant impact on the piping module design going through the main line. It presents an alternate to other method with separate deployment table generally retained for PLETs or In-Line Tees too large for the standard main line. This post installation process is patent pending.
Jack-St. Malo Marine Operator Training Simulator
Authors: Hudson Chris , Walker Kevin , Rastogi Ankur , Bhaumik Tirtharaj 
Published: June 2014

Abstract
A Marine Simulator was developed for the Jack-St. Malo field located in approximately 7000 feet of water in the Gulf of Mexico Walker Ridge block. The simulator presented operational information in a form similar to that on the actual facility and provided operational personnel with extensive operational experience and training on scenarios as may be faced in the actual facility, prior to and subsequent to facility start-up.
The design of the ballast system for this Semi-Submersible Floating Production Unit (FPU) called for a comprehensive training procedure as an added operational safety measure for the marine operators. The Jack-St. Malo Marine Simulator utilizes process and safety control configurations that are the same as the facility. It includes a Load Management system and an Environment and Facilities Monitoring System (EFMS) integrated with a high fidelity dynamic model for the hull ballast and bilge systems.
The simulator proved to be an effective tool to perform Control System checkout during pre-commissioning. Lifts for production, generation and compression modules were first tested on the Marine Simulator before actual lifts were conducted in the yard. Naval architects were consulted to verify anticipated ballasting operations before actual operations. The simulator gave operators a feel of the Process Dynamics, Process Control, and Safety System and familiarity with the Operator Station graphics well before start up. The simulator was successfully used as a dummy platform along with the Load Management Advisory Program to demonstrate the ballast procedure for the successive installation of three heavy modules onboard the actual platform. Scenarios simulated include hurricane shutdown and start-up, instrument failures, damaged mooring line situations and damaged compartment scenarios due to collision or inadvertent flooding, among many others.
Operator training to operate Jack-St. Malo ballast and bilge systems using facility Operator graphics and control system was thoroughly carried out using this Simulator and this contributed to the high level of confidence in hull commissioning operations including lifts and ballasting operations. The simulator was a useful tool for validating Standard Operating Procedures (SOP) before actual facility start-up.
Human Factors Analysis and Classification System (HFACS): Investigatory Tool for Human Factors in Offshore Operational Safety
Authors: Hollaway D.M.A. , Johnson J. D. 
Published: June 2014

It is axiomatic that 60 to 80 percent of mishaps are attributed to human error. The Human Factors Analysis and Classification System (HFACS) was developed by Dr. Scott Shappell and Dr. Douglas Wiegmann for the U.S. Navy to reduce human error in aircraft operations and maintenance. It is a broad human error framework that was originally used to investigate and analyze human factors aspects of aviation mishaps. HFACS is heavily based upon James Reason's ‘Swiss Cheese’ model of human error mishap causation. The HFACS framework provides a powerful tool to determine incident and accident root causal factors, generate leading indicators for potential mishaps, and target prevention efforts for maximum efficacy of loss prevention through systematic identification of active and latent failures within an organization. Moreover, the HFACS may be used to generate leading as well as lagging indicators for mishap prevention by applying to near-miss investigations.
HFACS has seen remarkable success in a variety of complex, tightly-coupled industries subject to large, catastrophic losses due to human error and organizational failure (aerospace, nuclear power generation, mining, construction, rail, and healthcare). The HFACS is adapted and presented for use in offshore operations involving offshore oil and gas exploration, production and support.
Mooring Integrity Management: A State-of-the-Art Review
Authors: Gordon Robert B. , Brown Martin G. , Allen Eric M. 
Published: June 2014

Abstract
There is consensus within the offshore oil & gas industry that there are too many instances of premature mooring line replacement and failure. In response to this situation, there has been rapid growth in mooring integrity related research and development. It has become difficult to keep track of all of this activity. The purpose of this paper is to provide a comprehensive review of the current state-of-the-art in mooring integrity management. Particular focus is given to coverage of the latest information on mooring failures, component degradation processes, monitoring and inspection technology, and mooring integrity management systems.
Thermodynamic State of Gas Hydrate in the Krishna-Godavari Basin Inferred From Well Log Analysis
Authors: Meyer Dylan W. , Flemings P.B. 
Published: June 2014

Abstract
We examined the in-situ hydrate saturations and salinities of gas hydrate-bearing sediments at National Gas Hydrates Project (NGHP) Site 01–10A in the Krishna-Godavari Basin, offshore India, to determine the thermodynamic state of the hydrate system. We determined hydrate saturations using logging-while-drilling (LWD) data in an iterative application of Archie's Law. The in-situ salinities were calculated from core-derived salinities by assuming that salts remained in the pore space, that the hydrate dissociated completely, and that pore volume remained constant with hydrate formation and dissociation. The in- situ salinity was compared to that required for three-phase equilibrium. We interpret two regions between 45 – 90 and 123 – 160 meters below seafloor (mbsf) where the system is at three-phase equilibrium at Site 01–10A.
Black Ore Cultivation Program in the Okinawa Trough
Authors: Saruhashi T. , Kyo M. , Sawada I. , Nozaki T. , Yokoyama T. , Seneviratne C. , Lim A.C. , Goi K.K , Teo S.G. 
Published: June 2014

JAMSTEC has an international patent for the environmentally-friendly cultivation system of hydrothermal chimney as the accessory product of scientific drilling program in the Okinawa Trough. We introduce the characteristics of natural and artificial hydrothermal vents in the Okinawa Trough, how this field was developed with special devices in the IODP Exp. 331, and new findings which lead to black ore cultivation system.
The topography around the hydrothermal vent was not flat surface in which conventional drilling guidebases cannot be used. A special guidebase, capable of inclinations up to 30 deg, was required for surface coring. The other challenge is the continuous flow from the hydrothermal vent whose maximum fluid temperature excessed 300 °C. Our research plan was to drill and cut the core through the guidebase, and set casing pipe and wellhead cap to collect pristine hydrothermal fluid by ROV.
The drilling and coring were successfully conducted through the guidebase deployed at 1000 mbsf (meter below sea floor). The retrieved core had high content of H2S gases which imposed us to wear breathing apparatus. Due to the high flow rate of 300 °C hotwater, the conventional bitumen core liners rapidly disintegrated. The hotwater producing from the top of wellhead cap has been vigorous with high flow rate in at least two years. The most remarkable finding was the highly rapid growth of sulfide chimney mainly composed of sphalerite, chalcopyrite and galena. After 25 months from the drilling, this sulfide chimney whose metal grade is higher than that of black-ore on land has grown to be 15 m in height. A new development plan was initiated to aim the cultivation of the chimney and efficient ore recovery. A custom-ordered cultivation tree attached to the wellhead cap is currently being developed.
JAMSTEC is planning to have the future expedition to launch the cultivation system at the Okinawa Trough for existing and additional wellhead. This expedition will focus on cultivation of the black ore from hydrothermal vent. The future planning of this project is also discussed in this paper.