The London Section Emerging Leaders Program (ELP) held its November function at a bowling center in London. It was a fun and informal evening and another great chance to meet with other London-based oil and gas industry professionals in a relaxed environment. The evening was well attended and included representatives from various petroleum disciplines throughout the London area, including students from Imperial College. In 2006, our objectives remain the same--to attract new members from a wider range of disciplines and to continue providing technical and social events for our colleagues in the London area. We also will be holding further sessions of the Champions program, aimed at answering the questions of final-year students at Imperial College, and will be extending the program to other universities.
Sawaryn, Steven J. (Consultant) | Wilson, Harry (Baker Hughes, a GE company) | Bang, Jon (Gyrodata Incorporated) | Nyrnes, Erik (Equinor ASA) | Sentance, Andy (Dynamic Graphics Incorporated) | Poedjono, Benny (Schlumberger) | Lowdon, Ross (Schlumberger) | Mitchell, Ian (Halliburton) | Codling, Jerry (Halliburton) | Clark, Peter J. (Chevron Energy Technology Company) | Allen, William T. (BP)
The well-collision-avoidance separation rule presented in this paper is a culmination of the work and consensus of industry experts from both operators and service companies in the SPE Wellbore Positioning Technical Section (WPTS). This is the second of two papers and complements the first paper, SPE-184730-PA (Sawaryn et al. 2018), which described the collision-avoidance management practices. These practices are fundamental in establishing the environment in which a minimum allowable separation distance (MASD) (in m) between two adjacent wells can be effectively applied. A standardized collision-avoidance rule is recommended, complete with parameter values appropriate to the management of health, safety, and environment (HSE) risk, and benchmarks for testing it. Together, these should help eliminate the disparate and occasionally contradictory methods currently in use.
The consequences of an unplanned intersection with an existing well can range from financial loss to a catastrophic blowout and loss of life. The process of well-collision avoidance involves rules that determine the allowable separation and the management of the associated directional planning and surveying activities. The proposed separation rule is dependent on the pedal-curve method and is expressed as a separation factor, a dimensionless number that is an adjusted center-to-center distance between wells divided by a function of the relative positional uncertainty between the two. The recommended values for the rule’s parameters result from a comparison of various industry models and experience. The relationships between key concepts such as the MASD and allowable deviation from the plan (ADP) are discussed, together with their interpretation and application. The dependency on the error distributions of the survey-instrument performance models used to establish the tolerance lines is also discussed.
The consequences of implementing a standardized separation rule across the industry are far-reaching. This affects slot separations, trajectories, drilling practices, surveying program, and well shut-in. We show how the MASD can be related to a probability of crossing and being in the unacceptable-risk region of an offset well. We show why this qualification is required for safe drilling practices to be preserved. Examples are presented in Appendices A through D to help the reader validate the calculations and the directional-drilling software necessary to perform them. The geometrical and statistical limitations of the methods are explained and areas are highlighted for further work. The methods outlined here, taken together with SPE-184730-MS, will improve efficiency in planning and executing wells and promote industry focus on the associated collision risks during drilling. The WPTS also supports the current development of API RP 78, Recommended Practices for Wellbore Positioning. Mathematical derivations or references are shown for all the calculations presented in the paper.
By International Petroleum Technology Conference (IPTC) Monday, 25 March 0900-1600 hours Instructors: Olivier Dubrule and Lukas Mosser, Imperial College London Deep Learning (DL) is already bringing game-changing applications to the petroleum industry, and this is certainly the beginning of an enduring trend. Many petroleum engineers and geoscientists are interested to know more about DL but are not sure where to start. This one-day course aims to provide this introduction. The first half of the course presents the formalism of Logistic Regression, Neural Networks and Convolutional Neural Networks and some of their applications. Much of the standard terminology used in DL applications is also presented. In the afternoon, the online environment associated with DL is discussed, from Python libraries to software repositories, including useful websites and big datasets. The last part of the course is spent discussing the most promising subsurface applications of DL.
Sawaryn, Steven J. (Consultant) | Wilson, Harry (Baker Hughes, a GE Company) | Allen, William T. (BP) | Clark, Peter J. (Chevron Energy Technology Company) | Mitchell, Ian (Halliburton) | Codling, Jerry (Halliburton) | Sentance, Andy (Dynamic Graphics, Incorporated) | Poedjono, Benny (Schlumberger) | Lowdon, Ross (Schlumberger) | Bang, Jon (Gyrodata Incorporated) | Nyrnes, Erik (Equinor ASA)
The well-collision-avoidance management and principles presented in this paper are a culmination of the work and consensus of industry experts from both operators and service companies in the SPE Wellbore Positioning Technical Section (WPTS). This is not a new subject, but current guidance is disparate, company-specific, and occasionally contradictory. As a result, the guidance can be difficult to understand and implement. A further aim is to drive the standardization of the well-collision-avoidance rules, process, and nomenclature throughout the industry. Standardization improves efficiency and reduces implementation errors.
The consequences of an unplanned intersection with an existing well can range from financial loss to a catastrophic blowout and loss of life. The process of well-collision avoidance involves rules that determine the allowable well separation, the management of the associated directional planning and surveying activities, and assurance and verification. The adoption of a specific minimum-allowable separation rule, no matter how conservative, does not ensure an acceptably low probability of collision. Many other factors contribute, such as the level of compliance by office and rig personnel with collision-avoidance procedures, and the completeness and correctness of the directional database. All these factors are connected.
The material is split into eight sections, each dealing with a critical element in the collision-avoidance process. Examples are presented to highlight a good-implementation practice. This aligned approach will dispel some of the current confusion in the industry concerning well-collision avoidance; will improve efficiency when planning and executing wells; and will build industry focus on the associated collision risks when drilling. The WPTS is also supporting the current development of API RP 78 (not yet issued).
This is the first of two papers. The second paper (Sawaryn et al. 2018) covers the minimum-allowable separation rule and its application, assurance, and verification.
Richard Dyson was named chief executive officer of io oil & gas consulting, an independent venture backed by GE Oil & Gas and McDermott. Dyson will be based in the company's head office in London and oversee its global operations, which include offices in Houston and Perth. Dyson has previously held various leadership roles, including the oversight of io's operations in Houston and London. He has experience leading feasibility and concept selection studies for international oil companies, national oil companies, and independent operators. Dyson holds a BSc in chemical engineering from the Unviersity of Surrey.
Recent drilling results have highlighted the potential for the development of Jurassic source rocks of southern England as a shale oil play. Sustained natural oil flows have been reported by UKOG (2015) from the tight, Lower Kimmeridge limestones in the Horse Hill-1 well. According to the operator, this discovery is naturally fractured and can be produced without hydraulic fracture stimulation.
The occurrence of shale gas in the UK has been known of since the nineteenth century, but development of this resource attracted very little interest until recent years (Selley, 2012; Andrews, 2014). The first exploration well in the United Kingdom that was specifically drilled for shale gas was Preese Hall-1 in northwest England in 2010. This well was hydraulically fractured in the Bowland Shale, but operations were suspended following reports of repeated seismicity caused by the injection of fluid during hydraulic fracture treatment (Green et al., 2012). Assessments of the Carboniferous shale gas potential of northern England and Scotland and of the Jurassic shale oil potential of southern England have been published by the BGS/DECC (Andrews, 2013, 2014; Monaghan, 2014). These studies listed the various criteria for evaluation of shale plays and provided broad descriptions and resource estimates for the Carboniferous and Jurassic shale plays in the United Kingdom.
This paper presents the results of an integrated petrophysical and geological assessment of the Jurassic sequence in the south of England. The study area stretched from the Weald and Vale of Pewsey Basins in the north to the onshore parts of the Portland–Isle of Wight Basin on the Dorset coast in the south (Figure 1). The evaluation focused on the Kimmeridge Clay Formation, the Oxford Clay Formation, the Downcliff Clay Member, Charmouth Mudstone Formation and the Blue Lias Formation.
The stratigraphic framework used for the study is based on the extrapolation of the well-known outcrop stratigraphy on the Dorset Coast to the study wells. Wireline log data and new sedimentological core description results were used to constrain facies mapping. Detailed sedimentological core description was carried out on three of the twelve study wells. From the trends observed in the wireline log data, the lithofacies and level of oxygenation, 14 initial facies associations were assigned over the cored intervals ranging from restricted shallow marine through shoreface to shelfal environments. These facies associations were grouped into seven combined facies associations which were used as input for the electrofacies analysis and facilitated the extrapolation of facies to intervals that lacked core data Additionally this workflow provided a useful template for estimating Total Organic Carbon TOC from logs using the CARBOLOG® equation and this resulted in a significant improvement in the correlation between the laboratory measured TOC values and the log-based TOC estimates. Results from the mineralogical analysis of core and cutting samples were utilised to calibrate and improve the petrophysical interpretations and to assess the elastic properties of the rocks in the intervals of interest. The petrophysical data, elastic properties and the facies interpretations were used to evaluate and map the development potential of the Jurassic source rock intervals as unconventional reservoirs.
An extensive geochemical database was combined with new analyses to characterise the source rocks. This data was integrated into 1-D basin models to identify and map effective source kitchen areas. The organic matter in the analysed interval is dominated by Type II kerogen, with significant input of Type III kerogen towards the London-Brabant Massif. The Upper Jurassic Kimmeridge Clay and the Oxford Clay are within the early oil window, while the Lower Jurassic Downcliff Clay Member, Charmouth Mudstone Formation and the Blue Lias Formation have reached peak oil maturity in the deeper parts of the Weald Basin. The source richness and kerogen types were combined with the maturity maps to create generation risk maps.
The risk for ground water contamination from hydraulic fracturing was also evaluated. These results were combined with the reservoir and generation risk maps to produce common risk segment maps in order to identify the sweet spots in the study area.
A drilling-and-completions-applications portfolio and its associated support services require constant attention if the portfolio is to remain up-to-date in both engineering and information technology (IT) terms and continue to serve the needs of the drilling-and-completions engineering community. Over time, this management effort has become more involved and complex as the number of available applications has increased and the technologies have changed. The trend toward tighter integration and data sharing between drilling-and-completions applications and with other disciplines applications such as subsurface, places data management at the heart of the response. For large organizations, in particular, keeping up with the new releases and patches can be a challenge, and the need for backwards compatibility is paramount. Data issues and the poor connectivity associated with physical remoteness and some nonrig-based units also can impede the change out to other systems. Special attention is required for applications that are designated safety-critical or safety-related.
This paper describes the way in which a major operator has defined and managed its drilling-and-completion portfolio during the last 20 years, to address the internal and industry changes and trends. The portfolio now serves the needs of more than 2,000 drilling-and-completions engineers worldwide. A wide range of examples, including the operator's WellAdvisor system, engineering toolkit, and wells/subsurface integration project, is presented, together with an evaluation of the portfolio-management challenges and successes that were achieved.
It is concluded that integration requires the consistent application of strong data-management principles and a commitment to an underlying architecture to support simplification, reducing the number and complexity of the interfaces that one must manage. However, some flexibility is needed to promote the development of, and access to, new applications, and the concept of niche applications was introduced to address technical specialist's needs. Some applications that are either company-specific or are needed only in special circumstances do not lend themselves to being commercial products, and these tools are provided by custom-built, Web-based applications. The recent focus on real-time data, quality of service, and digital security is merely the latest change that has had to be accommodated.
Despite the apparent rate at which technical and commercial changes are occurring, this paper's content illustrates the need to consider the portfolio-management issues over long cycle times. This paper will be of interest to both business and IT managers and engineers tasked with managing drilling, completions, and subsurface applications portfolios.
Caliper logs provide valuable information on the shape and wear of casing and tubing strings at various times throughout their operational life. In turn, this information is used to determine the remaining design strength. To clearly distinguish deformation and wear from deviations caused by manufacturing tolerance, the caliper measurements can be compared with a baseline log run soon after a tubular string has been run, or with surface-inspection data. However, a baseline log may not always be available. This paper addresses these situations and provides an assessment of the useful information that one can obtain. A mathematical model, based on the properties of the discrete Fourier transform, is presented to determine the caliper offset center and underlying tubular ovality from six or more equi-angularspaced caliper readings. The series-expansion approximation enables these parameters to be determined as a best fit from raw, uncentered data to a numerical accuracy of approximately 0.01% in a single pass. This is consistent with the accuracy and resolution of the currently available calipers. Complete numerical results from test cases based on exact geometric shapes, such as an offset circle and centered ellipse, plus field examples, are also included along with implementation notes. The same calculations can also be used to determine the underlying elliptic shape and orientation of an openhole caliper. In the casing specification API 5CT (2011), internal dimensions are indirectly described in relation to the unloaded casing or tubing outer diameter and wall thickness at surface conditions. The manufacturing tolerances and resulting uncertainties may be significant compared with the wear, but in some cases one can obtain useful information with corrections for downhole tension, temperature, and pressure effects. Details of these corrections and a discussion of other sensitivities are also provided. Such algorithms are usually considered by the service provider to be proprietary, and little quantitative material has been published on them or their interpretation. Also, data are often presented to the customer in only center-corrected form, which greatly restricts future reprocessing. This emphasizes the importance of acquiring and retaining the raw data.
VanZwieten, J.H. (Florida Atlantic University) | Baxley, W.E. (Florida Atlantic University) | Alsenas, G.M. (Florida Atlantic University) | Meyer, I. (Stellenbosch University) | Muglia, M. (University of North Carolina) | Lowcher, C. (University of North Carolina) | Bane, J. (University of North Carolina at Chapel Hill) | Gabr, M. (North Carolina State University) | He, R. (North Carolina State University) | Hudon, T. (PCCI) | Stevens, R. (Fugro-McClelland Marine Geosciences) | Duerr, A.E.S. (New West Technologies)
To assist in the development of mooring and foundation solutions for ocean current based electricity production, an overview of the resource and seafloor characteristics in three potential power production regions are presented. These regions are offshore Florida USA, North Carolina USA, and South Africa. Maximum measured flow speed off both the USA and South Africa were around 3.0 m/s and maximum temporally averaged energy densities were between 2.0 - 3.0 kW/m2. Water depths at considered locations range from 60-400 m, and bottom type varies greatly. Most evaluated locations contain occasional flow reversals and occasions when current speed approached 0.0 m/s (only locations near the core of the Gulfstream off SE Florida did not measure either event). While low current events are undesirable from energy production and mooring design perspectives, they might provide unique opportunities to install or maintain equipment.
The paper presents an exact analytical solution using higher-order functions for the deflection and buckling of a simple pipe stand in a derrick, modeled as an inclined slender column, with self-weight and pinned at both ends. The results are consistent with industry practice where an intermediate finger board is used to support 93-ft stands of both 2 3/8- and 2 7/8-in. steel pipe but is not required for 3 1/2-in. pipe. These observations suggest a suitable safety factor for application in other cases. The results are an important limiting case for the general pipe-stand model presented in Part 2. Buckling lengths are presented for a range of pipe sizes and types. Sensitivities, such as the presence of tool joints, differences in material, wear, and the effect of pipe stick-up above the top racking board are also introduced. Although there is good agreement between the theory and operational practice for triples, further investigation is needed for quads. Construction columns are normally designed to support significant loads, and in most cases, self-weight plays only a minor role. This is not the case for a simple pipe stand in a derrick, for which stability is solely dependent on self-weight. More-formal analysis of these conditions is warranted because of the trend of increased mechanization and the need to preserve safety and improve operational efficiency. To the author’s knowledge, there is no existing industry guidance for the flexing and stability of pipe stands in a derrick.