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The New Catastrophism by Derek Ager, Cambridge University Press, pp 231,
£22.95

Many readers of New Å®ÉúСÊÓƵ will recall the occasional pieces written by
the late Derek Ager on diverse scientific topics, and characterised by an
engaging and entertaining style. This style also epitomises The New
Catastrophism which, alas, must serve as his swan song. He covers a wide
range of geological incidents involving episodic rare and violent events
that warrant the term catastrophic. He endeavours to show that this kind of
sudden event dominates over gradual and continuous processes in the course
of geological history. The phenomena he discusses range from hurricanes to
episodic evolution and from colliding continents to asteroid impacts.

But The New Catastrophism is something of a disappointment. Ager’s basic
thesis is well known and carries an air of plausibility, but the new book
does not represent much of an advance on his well-received book The Nature
of the Stratigraphic Record, which was first published 20 years ago and went
through several editions. I was frustrated by the lack of rigorous argument
and supporting quantitative data. Why, for example, did he not cite the
important and well known research of Peter Sadler, who impressively
demonstrated for all types of sedimentary rocks an inverse correlation
between the inferred rate of sedimentation and the duration of the time
interval considered? This finding clearly implies that there are numerous
undetected gaps in the sedimentary sequence, a fact that should very much
have been grist to Ager’s mill.

When criticised for his iconoclastic views suggesting catastrophic
deposition for the Jurassic Sutton Stone conglomerate in Glamorgan, Wales,
he dismisses the critics more than once on the grounds that they belong to
the ‘Geological Survey establishment’, rather than endeavouring to refute
their arguments. This is not a scientific way of proceeding and it is simply
not good enough. Ager is equally uncritical about Warren Carey’s even more
iconoclastic expanding-Earth hypothesis, for which he admits a sneaking
sympathy. He airily disregards the reasoned and powerful case against this
theory put by many capable and well-informed geologists and geophysicists.

Ironically, Ager argues against catastrophism for mass extinction events,
preferring the more gradualistic scenario favoured by many palaeontologists.
Whether one prefers a bolide impact or terrestrially bound processes to
account for the extinctions at the end of the Cretaceous (65 million years
ago), which killed off much more than the dinosaurs, increasingly
persuasive evidence is emerging that the prime event was catastrophic in
geological terms – even if it took considerably longer than the few weeks to
months initially favoured by Luiz Alvarez and his supporters. Perhaps even
more impressive, the biggest mass extinction event of all, at the end of
the Palaeozoic (245 million years ago), appears to have had a major
catastrophic component, as indicated in Paul Wignall’s article (‘The day the
world nearly died’, New Å®ÉúСÊÓƵ, 25 January 1992).

There are many illustrations, both pictorial and anecdotal, and examples are
drawn from Ager’s personal experience in numerous countries across the
world. The writing is jargon-free, which makes the book accessible to a
wider public than just students and professionals.

Tony Hallam is a professor of geology at the University of Birmingham.