A common epithet addressed to critics of some topic or person or work is ‘the lowest form of life.’ Clearly, critical activity is both influential and hazardous. On this account, plus pressure of work, I was leery of the invitation to review the new book by Jens Havskov and Lars Ottemöller. However, my principal research activity involves earthquake seismology, so, in the hopes of finding a book useful for training students in basic analysis skills, I gulped, winnowed my work schedule and said, ‘OK’.
The book has a clear target audience: the routine analysts who manually process seismic network data. Their tasks are to determine locations, magnitudes, focal mechanisms and attenuation characteristics. The book contains some theoretical precursors, chapters devoted to each of these meat-and-potatoes topics, and some final ones on miscellaneous topics: array techniques and network operations. The approach could be characterized as suitably utilitarian.
A strength of the book is the assumption that operators will use one of the existing seismic data analysis systems. The authors have a fairly wide knowledge of present systems and data recording formats and present some useful critiques of them. The discussion of particular data recording formats is detailed and reveals the many considerations going into their definition. The final book chapter contains a less detailed summary of different processing system capabilities. Inevitably, both are useful, albeit imperfect representations of reality needing correction in later editions. (One ill-designed feature of SEED data records not included in the discussion: the merely heuristic way to determine data endianness, blockette 1000 notwithstanding.)
A weakness of the book is its non-uniform level of suitable detail. I yearn for a pithy and accurate discussion of the practical aspects of instrument response to which to direct all those e-mailed questions about what to do with poles and zeroes. The book's treatment includes two separate discussions (and notations) for analogue instrument response (free period and damping) and transfer functions (poles and zeroes). They have slightly different intents: one is instrument selection at the network design stage, while the other is handling instrument response. Only the latter is an analyst's (and a student's) concern. Frequency-amplitude-phase is mentioned but not discussed, and the units (f or ω convention) are unreported for various pole-zero responses given for the key instrument types to calculate magnitudes. A final example is the table of phases in the basic seismology chapter, which conflates a (scarily large) ray nomenclature list with amplitude measurement types.
If I were handed this book as a new employee of a seismic observatory, after reading it I'd know what the wiggles represented and what underpins the analyses I'd be doing with the software I'd be trained to use. As a research group leader, I'd recommend the chapters on signal processing and data formats for background and as an introduction to the topic. As a student text? No.
