Applied Depth Imaging
Course Description
Hydrocarbons are increasingly more difficult to find because reservoirs are often located in geologically complex areas. This geological complexity has motivated a significant paradigm shift from time imaging towards the extensive use of seismic depth imaging. Depth imaging improves the definition of the structural and stratigraphic frameworks and provides a better assessment and mitigation of risk in E&P. The goal of this course is for the participant to gain an understanding of the basic concepts and practical aspects used in building velocity models and seismic images in the depth domain in an intuitive manner. The participant will also be exposed to depth imaging practices currently in use by geophysicists and geoscientists through the description of workflows illustrated with synthetic and field data examples. The practical aspects are emphasized throughout the course. At the end of the course, the emerging depth imaging technologies are reviewed for the participant to make informed decisions about what technology to use in future E&P projects.
Course Objectives
The aim of this course is focused on depth imaging concepts and applications for complex geology areas. At the end of the course, the participant will be able to: 1. Understand the fundamentals of seismic migration; 2. Explain the pitfalls of time imaging; 3. Describe the differences between time and depth seismic imaging for simple and complex geological structures and stratigraphy; 4. Discuss basic seismic acquisition parameters influencing the quality of the seismic images in complex geology areas; 5. Understand the strengths and weaknesses of the most popular prestack depth migration methods; 6. Recognize the limitations of the seismic data to produce optimum seismic images for complex structural and stratigraphic frameworks; 7. Describe velocity estimation methods required for specific exploration and field development scenarios; 8. Explain the impact of velocity anisotropy on the quality of depth images and its effect on the spatial positioning of geological structures and well ties; 9. Define and/ or choose depth imaging workflows for specific E&P scenarios such as sub-salt, pre-salt, thrust belt, sub-basalt, complex carbonates and clastics; 10. Judge the quality of seismic depth images for a geologic interpretation; 11. Interpret depth-imaged data; 12. Make informed decisions to choose depth imaging workflows and technologies to be used in a given exploration or field development project; 13. Effectively communicate about emerging depth imaging methods and technology.
Course Outline
1. Introduction to the course. 2. Seismic migration fundamentals. 3. Understanding seismic velocities. 4. Practical understanding of velocity anisotropy. 5. Review of velocity estimation methods used for depth imaging. 6. Seismic data conditioning for depth imaging. 7. Isotropic and anisotropic velocity model building and imaging in practice. 8. Optimization of seismic images for a more reliable geologic interpretation. 9. Overview of emerging velocity model building and imaging methods.
Participants’ Profile
This course is designed for geophysicists, geoscientists and time processing and interpretation specialists seeking a practical understanding of depth velocity model building and imaging.
Prerequisites
It is desirable that the participants have a basic knowledge about seismic acquisition, processing and interpretation. Some basics of structural geology, stratigraphy and well logging are also desirable but not required.
Recommended Reading
Any general technical reading on basic seismic acquisition, seismic processing, time imaging, seismic interpretation, structural geology and/or salt tectonics will help to maximize the learning experience of the participant.
About the Instructor
Ruben D. Martinez is a Petroleum Geoscience Consultant and instructor with Reservoir Geoscience, LLC. He has been active in the seismic industry for 40 years. Martinez was associated with Geophysical Service Inc. (GSI) as R&D Reservoir Geophysicist, Halliburton Geophysical Services (HGS) and Western Geophysical as Senior Research Geophysicist, AGI as director of Seismic Reservoir Characterization and Petroleum GeoServices (PGS) as Manager Signal Processing R&D, VP Processing R&D, VP Seismic Processing Technology, Global Chief Geophysicist I&E and Chief Geophysicist I&E NSA. His responsibilities in PGS included directing global R&D and software commercialization of processing and imaging technologies. As Chief Geophysicist, he was responsible for the supervision and quality assurance of depth imaging projects, customer liaison, the promotion of best practices and the commercialization and use of high-end technology. Martinez is author and co-author of more than 70 technical papers published and/or presented at international conferences and 12 patents on seismic data acquisition, processing and imaging. He has also made numerous technical presentations at international conferences and has taught numerous courses and conducted seminars and workshops on seismic processing and imaging. In 2005, he was invited to present the annual Milton B. Dobrin lecture at the University of Houston. He is currently an instructor of the Continuing Education Program of the Society of Exploration Geophysicists (SEG) and the European Association of Geoscientists and Engineers (EAGE). He is a member of the SEG Board of Directors as Director at Large. Martinez was the recipient of the 2014 Mexican Association of Exploration Geophysicists (AMGE) geophysics award for life-long achievements to geophysics. He earned a BSc in Geophysics from the Instituto Politecnico Nacional (Mexico), MSc in Geophysics from the Colorado School of Mines and a PhD in Geosciences from the University of Texas at Dallas. He is a member of the Society of Exploration Geophyscists (SEG), European Association of Geoscientists and Engineers (EAGE), Geophysical Society of Houston (GSH), American Association of Petroleum Geologists (AAPG) and Asociacion Mexicana de Geofisicos de Exploracion (AMGE).