Subsurface Fluid Flow and Imaging: With Applications for Hydrology, Reservoir Engineering, and Geophysics
Some readers may scratch their heads when they see the title of this text. After all, it is not common to see subsurface flow as an imaging problem. However, there were in fact significant developments in the past couple of decades to turn the problem of subsurface flow characterisation into an imaging problem, like in geophysical tomography—the idea being that observations from different excitations are used to reconstruct the distribution of subsurface properties. Vasco and Datta-Gupta are among the pioneers in this field.
This text uniquely presents a unifying theory to tackle a wide range of subsurface imaging problems using trajectory-based techniques. By doing so, the same framework can be applied to wave-like hyperbolic problems, diffusive parabolic problems, and a mixture of the two. Both the mathematical formulation and asymptotic solutions of the imaging equations are presented, highlighting the efficiency and adequacy to describe spatially varying properties of these techniques. A key feature of trajectory-based modelling is that it separates the spatial heterogeneity from the transport computations themselves. By transforming coordinates to one where the time of flight is an independent variable along a trajectory, the 4-D problem can be solved in 2-D, where time and time of flight are the coordinates. Examples of the problems considered include transient pressure tomography, tracer response and transport tomography, multi-phase fluid flow and production tomography, geophysical time-lapse imaging, and imaging using deformation and strain.
As mentioned in its preface, this text is intended for imaging research practitioners. It is quite mathematically evolved because it aims to bridge the gap between imaging theories and subsurface applications. It is no easy introduction to geoscientists new to this topic, but I am sure those curious enough among us will read this text with great interest. The free software accompanying the book allows intuitive understanding of the concepts discussed, without worrying too much about the maths. For the academic researchers and industry practitioners working on subsurface characterization, this serves as an important and helpful reference. It should help us to appreciate the elegance of trajectory-based modelling and promote future applications. The book’s presentation is clear, systematic, innovative, and complete. It could benefit from having a summary chapter at the end of the book and not limiting its colour figures at the centre of the book.
Reviewed by Michael Tso
SUBSURFACE FLUID FLOW AND IMAGING: WITH APPLICATIONS FOR HYDROLOGY, RESERVOIR ENGINEERING, AND GEOPHYSICS, by Donald Wyman Vasco and Akhil Datta-Gupta, 2016. Published by: Cambridge University Press (HBK) ISBN: 9780521516334. List Price: £89.99. W:
http://www.cambridge.org/