| Detecting and localizing nuclear blasts was an essential stimulus of the actions undertaken in the 1960's to emplace seismological observatories on the seafloor. The plate-tectonic theory, in which the oceanic areas play a major role, greatly accelerated the evolution of modern oceanology. The contribution of Ifremer's department of Marine Geosciences, in helping to advance this area of research, has been significant since 1972. The need for refraction studies to explore the deep structure of the margins and ocean-continent transition zones led us to design a deep-sea Ocean Bottom Seismograph (OBS) MK I in 1975, rated to 6,000 metres depth. This system introduced, for the first time, the concept of "isolated seismic sensors". This principle was adopted... |
