EQUIDISTANCE ORDERING OF LARGE EARTHQUAKES IN THE AEGEAN AND SURROUNDING AREAS

Abstract Two earthquake groups with different depths in the Aegean and surrounding areas are examined as case studies in respect of their equidistance ordering, their similarities and differences. The first group includes 20 shallow depth shocks with magnitude equal to or larger than 7.0Ms, and the second group includes 15 intermediate depth shocks (Ms≥6.5) in the time range 1901–1985. Both groups are dominated by several typical isosceles triangles and one or two equilateral triangles located in the central part of the studied region. The dominant distances between pairs of earthquakes are about 200km, 400krn and 600km for the first group, and 100km, 200km and 300km for the second group. Comparison of spatial ordering in the Aegean region with that in North China shows many similar features indicating the potential geodynamic significance for the study of deep structure and processes in the upper mantle.