Rupture zones and active crustal deformation in southern Thessalia, central Greece

The Southern Thessalia fracture belt has been selected as an area for pilot multinational studies on short term earthquake prediction. Thus, geophysical information has been used (surface breakages, macroseismic fields, aftershock distribuition, hot springs, gravimetric data) to accurately define the rupture zones of the three strongest earthquakes in this belt during the present century (1954 M=7.0, 1957 M=6.8, 1980 M=6.5) It is found that the rupture zones of this three earthquakes have an approximately east-west trend, tend to about without significant overlap, cover the whole southernmost part of the Thessalia plain, and are due to normal type faulting. Furthermore, reliable fault plane solutions and seismic moment release rates have been used to show that the upper crust in this belt is seismically extending at a rate of 7 mm/yr in a N 6°W direction, and is vertically thinning at a rate of 3 mm/yr, which is in full agreement with normal faulting striking in a N 80? E direction.