Managing Safety & Risk Issues In Upstream Field Development - Case Studies

2009 ◽  
Author(s):  
Christina Phang ◽  
Jye Yng Voon
Keyword(s):  
Case Studies ◽  
Safety Risk ◽  
Field Development

Time-Lapse Seismic for Reservoir Management: Case Studies From Offshore Niger Delta, Nigeria

2016 ◽  
Vol 19 (03) ◽  
pp. 391-402
Author(s):  
Sunday Amoyedo ◽  
Emmanuel Ekut ◽  
Rasaki Salami ◽  
Liliana Goncalves-Ferreira ◽  
Pascal Desegaulx
Keyword(s):  
Case Studies ◽  
Niger Delta ◽  
Reservoir Management ◽  
Time Lapse ◽  
Seismic Survey ◽  
Elastic Model ◽  
Field Development ◽  
4D Seismic ◽  
The Impact

Summary This paper presents case studies focused on the interpretation and integration of seismic reservoir monitoring from several fields in conventional offshore and deepwater Niger Delta. The fields are characterized by different geological settings and development-maturity stages. We show different applications varying from qualitative to quantitative use of time-lapse (4D) seismic information. In the first case study, which is in shallow water, the field has specific reservoir-development challenges, simple geology, and is in phased development. On this field, 4D seismic, which was acquired several years ago, is characterized by poor seismic repeatability. Nevertheless, we show that because of improvements from seismic reprocessing, 4D seismic makes qualitative contributions to the ongoing field development. In the second case study, the field is characterized by complex geological settings. The 4D seismic is affected by overburden with strong lateral variations in velocity and steeply dipping structure (up to 40°). Prestack-depth-imaging (PSDM) 4D seismic is used in a more-qualitative manner to monitor gas injection, validate the geologic/reservoir models, optimize infill injector placement, and consequently, enhance field-development economics. The third case study presents a deep offshore field characterized by a complex depositional system for some reservoirs. In this example, good 4D-seismic repeatability (sum of source- and receiver-placement differences between surveys, dS+dR) is achieved, leading to an increased quantitative use of 4D monitoring for the assessment of sand/sand communication, mapping of oil/water (OWC) front, pressure evolution, and dynamic calibration of petro-elastic model (PEM), and also as a seismic-based production-logging tool. In addition, 4D seismic is used to update seismic interpretation, provide a better understanding of internal architecture of the reservoirs units, and, thereby, yield a more-robust reservoir model. The 4D seismic in this field is a key tool for field-development optimization and reservoir management. The last case study illustrates the need for seismic-feasibility studies to detect 4D responses related to production. In addition to assessing the impact of the field environment on the 4D- seismic signal, these studies also help in choosing the optimum seismic-survey type, design, and acquisition parameters. These studies would possibly lead to the adoption of new technologies such as broad-band streamer or nodes acquisition in the near future.

Introduction to this special section: AVO inversion

2019 ◽  
Vol 38 (10) ◽  
pp. 752-753
Author(s):  
Edward Townend ◽  
Michael Kemper
Keyword(s):  
Case Studies ◽  
Best Practice ◽  
Special Section ◽  
Leading Edge ◽  
Seismic Inversion ◽  
The Body ◽  
Amplitude Variation With Offset ◽  
Field Development ◽  
Avo Inversion ◽  
The Subject

It has been more than three years since The Leading Edge last published a special section on amplitude variation with offset (AVO) inversion, and interest in the subject remains strong. This past spring, SEG hosted a joint symposium in Houston, Texas, on the “Resurgence of seismic inversion,” and the body of talks and case studies demonstrated the method's continued relevance to making impactful drilling decisions. Despite this, and despite AVO inversion's position as a mature and well-established technique, there are an abundance of examples in which inaccurate AVO predictions have led to drastic failures at the drill bit. This highlights the challenges that still exist in the successful execution of such investigations and makes the subject occasionally controversial and certainly fraught with data-quality and best-practice considerations. In this vein, the special section presented here offers examples of the broad sweep of considerations and methods relevant to enabling successful AVO inversion and the interpretation of its products, as well as case studies that demonstrate how application of the technique can be impactful all the way through to appraisal and field development programs.

Role of high quality seismic data in field development and production through case studies from a giant offshore carbonate field, Abu Dhabi, UAE

2011 ◽  
Author(s):  
Akmal Sultan ◽  
Jie Zhang ◽  
H. Ewart. Edward ◽  
S. Ahmed Hage ◽  
Khaled Shahata ◽  
...  
Keyword(s):  
Case Studies ◽  
Seismic Data ◽  
Abu Dhabi ◽  
High Quality ◽  
Field Development

The Power of Real-Time Monitoring and Interpretation in Wireline Formation Testing-Case Studies

2007 ◽  
Vol 10 (03) ◽  
pp. 241-250 ◽  
Author(s):  
Hani Elshahawi ◽  
Mohamed Naguib Hashem ◽  
Daniel McKinney ◽  
Mario Ardila ◽  
Cosan Ayan
Keyword(s):  
Real Time ◽  
Case Studies ◽  
Real Time Monitoring ◽  
Time Data ◽  
Virtual Collaboration ◽  
Evaluation Program ◽  
Field Development ◽  
Reservoir Architecture ◽  
Fluid Analysis ◽  
Wide Range

Summary Modern wireline formation testers (WFTs) are able to collect a massive amount of data at multiple depths, thus helping to quantify changes in rock and fluid properties along the wellbore, to define hydraulic flow units, and to understand the reservoir architecture. They are being used routinely in a wide range of applications spanning pressure and mobility profiling vs. depth, fluid sampling, downhole fluid analysis (DFA), interval pressure-transient testing (IPTT), and microfracturing. Because of the complex tool strings and the elaborate operational aspects involved in wireline formation testing, success requires detailed upfront planning and procedural design as well as real-time operational and interpretational support. It is becoming increasingly critical for operating and service company experts to remotely monitor and interpret WFT surveys in real time through Web-based systems. The importance of meeting all rock and fluid data-acquisition objectives cannot be overstated, given the high cost of offshore operations and the implications of obtaining false or misleading information. The main objective of real-time monitoring remains to assure that the planned data are acquired according to pre-established procedures and contingency plans. However, even in developed reservoirs, unexpected circumstances arise, requiring immediate response and modifications to the preplanned job procedures. Unexpectedly low or high mobilities, probe plugging, unanticipated fluid types, the presence of multiple phases, and excessive fluid contamination are but a few examples of such circumstances that would require real-time decision making and procedural modifications. Real-time decisions may include acquiring more pressure data points, extending sampling depths to several zones, extending or shortening sampling times, and repeating microhydraulic fracture reopening/closure cycles, as well as real-time permeability, composition, or anisotropy interpretation to determine optimum transient durations. This paper describes several examples of formation tester surveys that have been remotely monitored in real time to ensure that all WFT evaluation objectives are met. The power of real-time monitoring and interpretation will be illustrated through these case studies. Introduction WFT has become a standard part of the evaluation program of most newly drilled wells, but the objectives vary from offshore deepwater exploration and appraisal wells to old cased-hole and development wells later in the life of a field. Given the wide range of applications and combinations, each WFT evaluation program is unique. Some may include only a pressure-gradient survey for reservoir depletion and communication information, whereas others may seek information on the precise nature of the hydrocarbon fluids and water in terms of chemical and physical properties, phase behavior, and commingling tendencies. Cased-hole surveys might look for bypassed hydrocarbon zones or have objectives that could not be achieved during the openhole phase. Regardless of the type of survey performed, understanding the exploration and appraisal or field-development objectives and translating these into acquisition objectives is essential for success. Figs. 1 and 2 schematically illustrate the real-time monitoring concept. Real-time data are viewable by authorized personnel anywhere around the world, thus allowing virtual collaboration between field staff and off-site service- and operating-company experts throughout the operation. This paper includes several examples of WFT surveys that were monitored and supervised in real time. The cases presented span the entire spectrum of WFT applications including pressures, gradients, sampling, downhole fluid analysis (DFA), IPTT, and microfracturing. The power of real time monitoring and interpretation is clearly illustrated by these examples.

Case Studies Illustrating the Use of Reservoir Simulation Results in the Reserves Estimation Process

2009 ◽  
Vol 12 (01) ◽  
pp. 149-158 ◽  
Author(s):  
Dean C. Rietz ◽  
Adnan H. Usmani
Keyword(s):  
Case Studies ◽  
Reservoir Simulation ◽  
High Performance ◽  
Oil And Gas ◽  
Numerical Models ◽  
Simulation Software ◽  
Probabilistic Methods ◽  
Field Development ◽  
Estimation Process ◽  
Simulation Results

Summary Continuous improvements in reservoir simulation software and the availability of high performance computing equipment are making the use of simulation models commonplace for field development and planning purposes. Naturally, this trend has also increased interest in the use of reservoir simulation model results in the oil and gas reserves estimation process. As simulation specialists who work in a primarily reserves-evaluation company, the authors are routinely asked to evaluate, and in many cases incorporate, simulation results in the reserves estimation process. In addition, the authors are required to opine on the approach and tactics used by clients while they incorporate numerical models in their reserves bookings. Because limited published discussion exists on this topic, the purpose of this paper is to provide some examples of the approach used by the authors. We believe this approach to be appropriate and within the spirit of reserves interpretation as used by typical reserves regulatory bodies such as the U.S. Securities and Exchange Commission (SEC). Papers previously published have discussed the use of models in the reserves process, including the evaluation of the models themselves (Palke and Rietz 2001; Rietz and Usmani 2005). In contrast, this paper provides three case studies that illustrate how results from various models have been used to assist in quantifying reserves. Two of the examples are based on history-matched models, while the third focuses on a pre-production reservoir where no adequate history is available and probabilistic methods were incorporated to help understand the uncertainty in the forecasts. While there is no "cookbook" or step-by-step procedure for using simulation results to estimate reserves, the case studies presented in this paper are intended to both show some examples and also spark some debate and discussion. Undoubtedly there will be some disagreement with our techniques, but an open discussion should prove to be beneficial for both reserves evaluators and simulation specialists.

Sign in / Sign up

Export Citation Format

Share Document