Seismic Fracture Characterization: Concepts and Practical Applications
Course Description
The ability to identify fracture clusters and corridors and their prevalent directions within many carbonates and unconventional resources (shale gas, tight gas and tight oil reservoirs) can have a significant impact on field development planning as well as on the placement of individual wells. The characterization of natural fractures is difficult and cannot be achieved by any single discipline or single measurement. Geophysics can identify spatial distributions of fractures and fracture corridors between wells and seismically-derived fracture information to complement (not compete with) other measurements, such as outcrops, core, FMI, cross-dipole and other fracture information. This course is an introduction to the fundamental concepts of seismic fracture characterization by introducing seismic anisotropy, equivalent-medium representation theories of fractured rock and methodologies for extracting fracture parameters from seismic data. With a focus on practical applications, three case studies are presented to demonstrate the applicability, workflow and limitations of this technology: a physical laboratory 3D experiment where fracture distributions are known, a Middle East fractured carbonate reservoir and a fractured tight gas reservoir.
Course Objectives
Upon completion of the course, participants will be able to: • Understand key geological aspects of fractures and their roles in hydrocarbon exploration and production; • Understand the fundamental concept of seismic anisotropy and the equivalent medium representation of fractured rock; • Understand the principal methodologies of seismic fracture characterization using shear-wave splitting and azimuthal variation of seismic attributes; • Understand the basic data requirement, assumptions, limitations and applicability of seismic fracture prediction technology; • Apply practical workflow introduced in this course to real seismic data; • Interpret and integrate seismically-derived fractures with other measurements.
Course Outline
• Introduction: key geological elements • Fundamental seismic anisotropy • Equivalent medium representation of fractured rock • Fracture characterization using P-wave data • Shear-waves and applications of multicomponent seismology • Case study 1: 3D Physical laboratory data • Case study 2: An example from offshore Middle East carbonate reservoir • Case study 3: An example from tight gas reservoir • Summary and road ahead
Participants’ Profile
The integrated nature of this subject means that the book and the associated course are purposely designed for individuals from all subsurface disciplines including geophysics, geomechanics, rock physics, petrophysics, geology, reservoir modeling and reservoir engineering.
Prerequisites
None. Students as well as experienced geoscientists and engineers should benefit from this course.
About the Instructor
Dr Enru Liu has over twenty-five years of experience working in rock physics, poroelasticity, seismic anisotropy, multicomponent seismology, fracture modelling/characterisation, modelling wave propagation in complex media, seismic attribute analysis and interpretation. He received a BSc in geophysics from the Changchun Geological Institute (now part of the Jilin University, China) and a PhD in geophysics from the University of Edinburgh (UK). He was a Principal Research Scientist at the British Geological Survey (BGS) until March 2007 when he joined ExxonMobil Upstream Research Company (EMURC). While at BGS, he was the principal researcher of the Edinburgh Anisotropy Project — an industry sponsored research consortium since 1988 and was the Principal Investigator of several industry and UK research council funded projects including the NERC Micro-to-Macro programme. He is currently a research associate in the Geophysics Division of EMURC. He has published over 80 papers in peer-reviewed journals on the subject covered in this course. He was an honorary/visiting professor at the China University of Mining and Technology (2003-2007), an honorary fellow of the University of Edinburgh (2005-2008) and a member of the Peer Review College of the UK Natural Environment Research Council (2006-2007). He is a member of the SEG Research Committee, the SEG Development & Production Committee, the EAGE Research Committee and a member of the Editorial Boards of Geophysical Prospecting (2000-2011) and Journal of Seismic Exploration (since 2008). He was the co-recipient of the Cagniard Award from EAGE in 2007 and received an honourable mention of a co-authored paper published in The Leading Edge in 2007.