Debate

Unfortunately, it is typical for debates about earthquake prediction research to be based in part on incorrect assertions^1,2. The first two sentences in the moderator's introduction follow this tradition. Contrary to his suggestion, the recent earthquake in Colombia has done nothing to show the inability or ability of science to predict earthquakes, because this problem simply has not been studied in Colombia.

For the public, the main question that seismologists should ask themselves is, "Can earthquakes be predicted?". Nature's earthquake prediction debate follows this simple line of inquiry, although presented in a slightly more subtle form by Ian Main: "How accurately and reliably can we predict earthquakes, and how far can we go in investigating the degree of predictability that might exist?" This is still, however, a question formulated under social pressure. I argue that this question should be left to one side by scientists to allow progress in a more general and comprehensive framework, by studying the whole set of crustal instabilities — or 'transients' — and not only earthquake precursors.

Because large earthquakes release huge amounts of energy, many researchers have thought that there ought to be some precursory phenomena that could be consistently observed and identified, and used as the basis for making reliable and accurate predictions. Over the past 100 years, and particularly since 1960, great efforts, all unsuccessful, have been made to find such hypothetical precursors. For further details see my review¹, which includes eight pages of references (in 6-point type, to save space) to this vast body of work.

Regular e-mailer, Norman Macleod's, once more takes up the cudgel against those who would make extensive use of stratigraphic data.

In the final week of this Nature debate the moderator, Andrew Smith, draws together the main threads that have run through the contributions.

The responses to Norman Macleod's previous e-mail contribution were such tahe this week we have given him the opportunity to respond.

The polarization seen in this debate arises, says Dr Dan Fisher, from a desire for both sides to argue over different questions. He cautions that the zeal of cladists to discard stratigraphic data as irrelevant is in danger of throwing out the baby with the bath water.

Is the incompleteness of the fossil record any reason to exclude the information that it contains? Professor Chris Paul argues that stratigraphic data is being treated inconsistently compared to other forms of data.

A model is only as good as the assumptions and data on which it is based. Here Dr Peter Forey takes issue with earlier contributors who wish to use incomplete stratigraphic data when constructing phylogenies. He argues that these data are better employed as independent checks once a phylogenetic theory has been proposed.

One of this week's email contributors takes to task those who would hold up the foraminifera as an example of a gap free fossil record.