  Seismology has several features that suggest it is a highly internationalized
field: the subject matter is global, the tools used to analyse seismic waves
are dependent upon information technologies, and governments are interested in
funding cooperative research. We explore whether an emerging field like
seismology has a more internationalised structure than the older, related field
of geophysics. Using aggregated journal-journal citations, we first show that,
within the citing environment, seismology emerged from within geophysics as its
own field in the 1990s. The bibliographic analysis, however, does not show that
seismology is more internationalised than geophysics: in 2000, seismology had a
lower percentage of all articles co-authored on an international basis.
Nevertheless, social network analysis shows that the core group of cooperating
countries within seismology is proportionately larger and more distributed than
that within geophysics. While the latter exhibits an established network with a
hierarchy, the formation of a field in terms of new partnership relations is
ongoing in seismology.
