On the basis of the 1998 case history, the authors discuss the possibility of using the shape of the debris flows to predict the degree of hazard. The most vulnerable setting is characterized by basins with a steep average slope and a triangular shape with the base up-valley. In order to estimate the time interval over which these extinctions took place, the authors used sedimentary cycles that record known astronomical cycles of Earth's orbit. Using the improved resolution provided by the cycle analysis, the authors find that the dramatic change in the faunal record that marks the P-T boundary took place over less than 60,000 years, and perhaps as rapidly as less than 8,000 years. These results are compatible with a catastrophic cause for the extinctions.
Historical data are fundamental to the understanding of the seismic history of an area.
At the same time, knowledge of the active tectonic processes allows us to understand how earthquakes have been perceived and recorded in legends and myths by past cultures. Delphi, positioned above the surface expression of one of the major active faults that controls the tectonic depression of the Gulf of Corinth, is a key area for improving our understanding of the seismotectonic behavior of this region. Integration of geological data, archaeological evidence, and historical sources suggests that in the earthquake of 373 B.C., ground ruptures, due to slip on the fault plane, opened not only at Helice on the principal fault of the tectonic depression, but also on the opposite fault at Delphi. Such a mechanism would have been similar to what observed in the earthquake of 1981 near Corinth. The Delphic oracle, by far the most venerated oracle of the Greek ancient world, has been worshiped since its remote origins almost 2000 years ago.