Copyright 2019 held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA) and the submitting authors. ABSTRACT Today, many machine learning techniques are regularly employed in petrophysical modelling such as cluster analysis, neural networks, fuzzy logic, self-organising maps, genetic algorithm, principal component analysis etc. While each of these methods has its strengths and weaknesses, one of the challenges to most of the existing techniques is how to best handle the variety of dynamic ranges present in petrophysical input data. Mixing input data with logarithmic variation (such as resistivity) and linear variation (such as gamma ray) while effectively balancing the weight of each variable can be particularly difficult to manage. DTA is conceived based on extensive research conducted in the field of CFD (Computational Fluid Dynamics). This paper is focused on the application of DTA to petrophysics and its fundamental distinction from various other statistical methods adopted in the industry. Case studies are shown, predicting porosity and permeability for a variety of scenarios using the DTA method and other techniques. The results from the various methods are compared, and the robustness of DTA is illustrated. The example datasets are drawn from public databases within the Norwegian and Dutch sectors of the North Sea, and Western Australia, some of which have a rich set of input data including logs, core, and reservoir characterisation from which to build a model, while others have relatively sparse data available allowing for an analysis of the effectiveness of the method when both rich and poor training data are available. The paper concludes with recommendations on the best way to use DTA in real-time to predict porosity and permeability. INTRODUCTION The seismic shift in the data analytics landscape after the Macondo disaster has produced intensive focus on the accuracy and precision of prediction of pore pressure and petrophysical parameters.
Hurlburt, Maurice (Athabasca Oil Corp.) | Quintero, Jonathan (Baker Hughes, a GE Company) | Bradshaw, Robert (Baker Hughes, a GE Company) | Belloso, Andres (Baker Hughes, a GE Company) | Cripps, Evan (Baker Hughes, a GE Company) | Blakney, Donya (Baker Hughes, a GE Company) | Glass, Darnell (Baker Hughes, a GE Company)
A Canadian oil & gas operator has been setting new benchmarks drilling the vertical and tangent section of Montney horizontal wells in the Placid field of Northern Alberta. Initially, the operator drilled vertical wells to kick off point (KOP) with polycrystalline diamond compacts (PDC) and conventional mud motors. As a result of increasing well density, however, the well plans consistently required a 15° to 30° tangent section. With PDC drilling, toolface and build up rates were problematic and the sliding rate of penetration (ROP) was slow.
A Rotary Steerable System (RSS) was introduced, but despite the improved performance, the technology came at a premium cost and the severity of drilling dysfunctions generated an increase in tool failures. With falling oil prices, a more cost effective solution was required.
Hybrid bit technology, which combines the cutting mechanism of both fixed cutter and roller-cone bits, has been extensively utilized in Canada to drill build sections, providing outstanding results. They have not, however, been commonly used to drill the vertical (drill-out) and tangent sections. The operator combined a state-of-the-art hybrid bit with a mud motor to drill the interval with an 85% success rate. The combination of the hybrid bit and conventional motor, compared to PDC and RSS, resulted in a 30% cost savings to complete the interval.
The present case study outlines how hybrid bit technology development, driven by field data in a continuous improvement cycle, identifies performance opportunities, which have a significant impact on drilling time and cost savings in drill out sections. The overall objective of this current case study is to highlight the results and lessons learned throughout the implementation process.
DCN Diving has received a contract from Dana Petroleum to execute work offshore the Netherlands. The DP-012 pipeline links the Dutch P15D and P11B (De Ruyter) platforms, which are located in the Dutch North Sea. The scope of work includes diving and support for dredging and remotely operated vehicles. DCN Diving said that work should begin in June. Dana Petroleum operates the De Ruyter platform, which is located in 114 ft water depth approximately 37 miles northwest of The Hague.
DCN Diving has received a contract from Dana Petroleum to execute work offshore the Netherlands. Under the terms of the deal, DCN will perform the fabrication, installation, and precommissioning of various tie-in spools and a flanged connector for Dana’s DP-012 gas export pipeline. The DP-012 pipeline links the Dutch P15D and P11B (De Ruyter) platforms, which are located in the Dutch North Sea. The scope of work includes diving and support for dredging and remotely operated vehicles. DCN Diving said that work should begin in June.
Under the terms of the deal, DCN will perform the fabrication, installation, and precommissioning of various tie-in spools and a flanged connector for Dana’s DP-012 gas export pipeline. The DP-012 pipeline links the Dutch P15D and P11B (De Ruyter) platforms, which are located in the Dutch North Sea. The scope of work includes diving and support for dredging and remotely operated vehicles. DCN Diving said that work should begin in June. Dana Petroleum operates the De Ruyter platform, which is located in 114 ft water depth approximately 37 miles northwest of The Hague.
Temizel, Cenk (Aera Energy) | Irani, Mazda (Ashaw Energy) | Canbaz, Celal Hakan (Schlumberger) | Palabiyik, Yildiray (Istanbul Technical University) | Moreno, Raul (CSmart Recovery) | Diaz, Jose M. (VCG O&G Consultants) | Tao, Tao (Texas Southern University) | Alkouh, Ahmad (College of Technological Studies)
Along with the advances in technology, greener technologies that help to minimize carbon footprints are becoming more common in oilfield applications as well as other areas. Electrical heating is one of the relatively more environmentally-friendly heavy oil recovery technologies that is not new but has gained more popularity with the advances in electrical heating equipment and the technologies within the last decade offering longer and reliable operations that led to its use as a standalone recovery method rather than only a preheating method. In this study, a comprehensive investigation of the production optimization is outlined that includes not only the reservoir aspects but also the production and facility aspects of electrical heating in heavy oil reservoirs. A full-physics commercial simulator has been coupled with an optimization/uncertainty tool to understand the significance of uncertainty and control variables that influence the production function in addition to the analysis of normalized type curves in different real field cases. The challenges encountered during implementation of electrical heating processes in terms of production, reservoir and facilities engineering are outlined in order to provide a comprehensive and practical implementation perspective rather than only theoretical and/or simulation work. It is observed that electrical heating can be promising when applied in the right place and can bring lots of benefits not only in terms of low water-cut recovery, but also low carbon footprint and low costs associated with environmental fees. The significant parameters are listed for a robust and successful implementation of an electrical heating project. There are studies on electrical heating, but they are either outdated reflecting the old technology, or only focusing on simulation/theoretical work or only case focusing only reservoir or production aspects. This study fills the gap and provides a comprehensive look in detail in the theory, real-field practical problems and solutions from source of electricity to production of the heavy oil illustrating the costs associated that can serve as a solid reference for future implementations. 2 SPE-193707-MS
In the search for energy, new technologies bring added benefits. These new technologies are driven by the need to be more environmentally conscious, reduce costs, increase reliability, reach farther and deeper, and provide more and better data to more effectively manage wells and equipment. With these new technologies, the industry is making a steady transition toward electrification and digitalization of the well completion. Electrification of completion equipment has occurred at a steady pace for several years, but the pace has quickened as the reliability of equipment has improved and the benefits of additional data have been realized. Within the last few years, the first completions with all-electric Christmas trees (XT) were run. Because all-electric tubing retrievable downhole safety valves were not yet available, these were not true all-electric completions. These first wells required the XTs to be installed with hydraulically operated downhole safety valves, making these mixed-technology completions. Recently, an all-electric tubing retrievable downhole safety valve was developed, qualified, and field tested. The introduction of the all-electric tubing retrievable downhole safety valve will bring the benefits of an all-electric completion to the oil industry.
All-electric tubing retrievable downhole safety valves, also known as electric surface-controlled subsurface safety valves (ESCSSV), build upon field proven technology, but offer the added benefits that an electrically operated tool can provide while performing the same critical function as the traditional hydraulic downhole safety valve.
This paper describes the development and deployment of the ESCSSV; it includes discussions about the qualification program of the valve and valve systems, integration with the all-electric subsea XT and control system, and installation in the well.
… And expecting different results. Electrical heating of oil reservoirs has fascinated petroleum engineers for more than 70 years - longer, if you include the use of heaters in Siberian oilfields. The earliest laboratory study was done in Pennsylvania in 1940's. Since then, many more studies and field tests have been carried out, none of which was a commercial success. This paper takes a look at different forms of electrical heating, the supporting theoretical work, and field tests. Additionally, several examples are given illustrating the limitations of electrical heating processes. Also discussed is the logic behind the resurgence of electrical heating in recent years. Not discussed are over 200 patents on electrical heating. The major electrical heating processes are resistance heating, using direct current or low frequency alternating current, induction heating, microwave heating, and heating by means of electrical heaters. These are described briefly, and compared. In applications to oil sands, the intent is to utilize the connate water as the heating element (resistance heating) or oil sands as the dielectric (microwave heating). Induction heating is much less effective but has been tested in many field projects. Shale that has a permeability of zero to fluid flow, is electrically conductive, and thus channels much of the electric current flow in resistance heating, which also has other limitations. Microwaves suffer from low depth of penetration (of the order of 20 cm in oil sands) and low power delivery (of the order of 1 MW as a maximum). The power requirements for a typical SAGD pair, in contrast, are 15-30 MW. Electric heaters have been used in oilfields for many years for near-wellbore heating. Two large field pilots used powerful electric heaters, and were recently shut down. Although electrical heating has not had commercial success, recently there has been a resurgence in various electrical processes, as a means of reducing GHG emissions, under the flawed logic that oilfield use of electricity would displace emissions caused by steam generation.
A rotating tension anchor was developed to improve the cement bond by enabling rotation of the production casing of steam injection wells during cementing. This would be a world-first application of this casing pre-tensioning system in the application of steam well design.
A good cement bond is crucial for the integrity of a well; this is especially true in the harsh environment created by a 300°C injection temperature in steam well applications. A common and relatively simple approach to improve the cement bond quality is to rotate the casing during cementing. The rotation creates a helical flow pattern, which has an improved displacement efficiency compared to a uniaxial flow.
The design of steam injection wells in this heavy oil field requires a deep-set anchor to pre-tension the casing string with the required pick-up force. The existing anchor system had to be engineered and modified to enable casing rotation during cementing.
Although no breach of integrity has been found in previous steam injection wells, the operator identified improvement potential for the long term cement integrity through ultra-sonic cement bond measurements of existing wells. The 7-in production casing of a steam injection well was pre-tensioned with 264.000 lbs [120 metric tons] overpull and rotated with 20 revolutions per minute during cementing.
This world-first field trial of a rotating anchor tensioning system demonstrates, that the existing tension anchor system can be modified to enable rotation of the casing. An ultra sonic cement bond run, several weeks after cementing, confirmed that use of this equipment produced an improved cement bond quality compared to offset wells of similar age and status.
Control system failures in subsea operations are a leading cause of Blowout Preventer (BOP) down-time. The cost of these failures can increase exponentially with water depth. Legacy BOP control systems are based on 90-year-old hydraulics technology and have been stretched to cope with new regulatory requirements and harsher environments. The industry has responded to these design requirements by increasing component sizes, weights, and system complexities. These adaptations have resulted in unintended consequences, such as reduced reliability and an increase in wellhead loading. As subsea operations move into deeper water and wellhead pressures increase above 15,000 psi, legacy control systems may have reached their design limit. This paper introduces a new concept of an all-electric BOP, a game-changing technology that will not only negate these issues, but also improve the safety, efficiency, reliability, and functionality of subsea BOP control systems.