|Theme||Visible||Selectable||Appearance||Zoom Range (now: 0)|
Chen, Defei (PetroChina Tarim Oilfield Company) | Huang, Kun (PetroChina Tarim Oilfield Company) | Meng, Xiangjuan (PetroChina Tarim Oilfield Company) | Liu, Ju (PetroChina Tarim Oilfield Company) | Zhang, Bao (PetroChina Tarim Oilfield Company) | Sun, Tao (PetroChina Tarim Oilfield Company) | Shen, Jianxin (PetroChina Tarim Oilfield Company) | Wei, Junhui (PetroChina Tarim Oilfield Company) | Wu, Hongjun (PetroChina Tarim Oilfield Company) | Teng, Qi (PetroChina Tarim Oilfield Company)
Abstract Gas injection has become an important means of enhancing oil recovery (EOR) in clastic reservoirs, the Donghe Oilfield, Tarim, has been undergoing gas injection to enhanced oil recovery. During the gas injection, dynamic justification of gas injection was the most severe challenges, which needed to monitor the pressure profile, temperature profile and gas injection profile. Therefore, monitoring gas injection profile has becoming an important part of gas drive reservoirs. Donghe Oilfield was characterized by ultra-deep (>6000m), high temperature (>140°C) and high content of carbon dioxide, conventional manometer and thermometer cannot meet the downhole condition of ultra-deep and high temperature. To continuously monitor gas injection well, permanent fibre-optic surveillance technique featured with outstanding conformance, nice corrosion resistance and long-life span was developed, and a program was developed to use real-time fiber-optic Distributed Temperature Sensing (DTS) and Distributed Acoustic sensing (DAS) to identify the gas injection profile (gas channeling). Monitoring principle and system assembly of the fibre-optic was demonstrated in detail, the DTS utilized Joule - Thompson cooling principle as the gas injected into formation through screen pipe, while the DAS captured the amplitude and frequency of acoustics from the gas flow. DTS and DAS data obtained at the same time by using fiber wireline outside the gas injection string during gas injection. There was a field application in gas injection well of DH1-H3 and gas injection profiles derived from DTS and DAS had the extremely high consistency to radioactive tracer profiles run at about the same time and under similar injection rates and pressure. The success of the fibre-optic surveillance in DH1-H3 exhibited great potential of fiber-optic sensing in gas injection EOR projects, which could provide a new and effective tool in identifying gas channeling.
Cars and earthquakes induce Rayleigh waves that are recorded on a roadside section of the Stanford DAS-2 fiber array. They can be directly used for near-surface S-wave velocity inversion. Cars driving along the road and small earthquakes excite Rayleigh waves with complementary frequency bands. The surface waves induced by passing cars have a consistent fundamental mode and a noisier first mode. By stacking dispersion images of 33 passing cars recorded in the same section of the DAS array, we obtain a stable dispersion image with two clear modes. The frequency range of the fundamental mode can be extended by adding the lowfrequency earthquake-induced Rayleigh waves. In order to assure clear separation from Love waves and aligning apparent velocity with phase velocity, we choose an earthquake that is approximately in line with the array. Thanks to the extended frequency range, we can achieve better depth coverage and resolution for shear-wave inversion. The inverted models match those obtained by a conventional geophone survey performed using active sources. Processing car-induced surface waves is dramatically cheaper than interferometry and reliable estimates can be obtained more frequently because surface wave analysis do not require convergence of the interferometric analysis. Furthermore, in order to automate the □ imaging process, we introduce a new objective function that avoids manual dispersion curve picking. Presentation Date: Monday, October 12, 2020 Session Start Time: 1:50 PM Presentation Time: 4:45 PM Location: 351D Presentation Type: Oral
Horst, Juun van (Shell International E&P) | Panhuis, Peter in (Shell International E&P) | Al-Bulushi, Nabil (Shell International E&P) | Deitrick, Greg (Shell International E&P) | Mustafina, Daria (Shell International E&P) | Hemink, Gijs (Shell International E&P) | Groen, Lex (Shell International E&P) | Potters, Hans (Shell International E&P) | Mjeni, Rifaat (Petroleum Development Oman) | Awan, Kamran (Petroleum Development Oman) | Rajhi, Salma (Petroleum Development Oman) | Bakker, Goos (Petroleum Development Oman)
Abstract In the past decade, Fiber-Optic (FO) based sensing has opened up opportunities for in-well reservoir surveillance in the oil and gas industry. Distributed Temperature Sensing (DTS) has been used in applications such as steam front monitoring in thermal EOR and injection conformance monitoring in waterflood projects using (improved) warmback analysis and FO based pressure gauges are deployed commonly. In recent years1 significant progress has also been made to mature other, new FO based surveillance methods such as the application of Distributed Strain Sensing (DSS) for monitoring reservoir compaction and well deformation, multidrop Distributed Pressure Sensing (DPS) for fluid level determination, and Distributed Acoustic Sensing (DAS) for geophysical and production/injection profiling. For the latter application, numerous field surveys were conducted to develop the evaluation algorithms or workflows which convert the DAS noise recordings into flow rates from individual zones. The applicability of a new graphical user-interface has been expanded to include smart producers and injectors that allows the user to visualize (in real time), QC and evaluate the DAS data. Also, the evaluation methods for the use of DTS for warmback analysis have been significantly improved. There are still improvements to be made in enabling Distributed Sensing infrastructure, such as handling and evaluation of very large data volumes, seamless FO data transfer, the robustness & cost of the FO system installation in subsea installations, and the overall integration of FO surveillance into traditional workflows. It will take some time before all these issues are addressed but we believe that FO based applications will play a key role in future well and reservoir surveillance. In this paper we present a recent example of single-phase flow profiling using DAS. The example is from a long horizontal, smart polymer injector operated by Petroleum Development Oman (PDO).
Abstract Fiber-optic sensing technology for in-well applications has traditionally focused on temperature profiling. This has limited the application of fiber-optic reservoir surveillance to recovery processes with a pronounced thermal signature. Currently, novel fiber-optic technologies entering the market promise a much wider range of subsurface measurements. This opens new avenues in well and reservoir management and highlights the opportunity for fiber-optics to become a pervasive oilfield technology. In this paper we discuss field trials that combine Distributed Temperature Sensing (DTS), Distributed Strain Sensing (DSS) and Distributed Acoustic Sensing (DAS). These trials demonstrate the potential of fiber-optic sensing technology for well integrity monitoring, gas lift optimization, in-flow profiling and downhole seismic acquisition. Esential to realizing this potential is the development of cost-effective, easy-to-deploy fiber-optic cables optimized for these various fiber-optic measurements. We also highlight the business integration challenge of handling, storing, and interpreting data volumes that in some applications reaches levels of 1 TB/well/day. We conclude that while significant technology challenges remain, with a broad cross section of oilfield technology providers working on derisking fiber-optic sensing technologies, the industry is on the verge of a step change in well and reservoir monitoring capability. Introduction Its passive nature and inherent long-term reliability, combined with the ability to string together numerous individual sensing elements in a single fiber, makes fiber-optic technology ideally suited for distributed sensing in harsh and remote environments. Despite this compelling proposition, for many years this technology was synonymous with temperature sensing and thereby limited to the monitoring of well operations and recovery processes with a pronounced thermal signature. In recent years, this situation has started to change rapidly. A variety of fiber-optic sensors developed in the aerospace and defense industries are finding their way into the oil and gas industry. As multiple fibers, each providing a specific distributed measurement, can be bundled in a single downhole-deployable cable, the industry is facing a unique opportunity for robust well and reservoir surveillance based on an abundance of measurements continuous in time during the well's productive life and continuous along its well path.