  In this work the data of the earthquake catalog of the NOAA, National
Geophysical Data Center (NGDC) are processed in terms of global seismic energy
release. The determined Global Cumulative Seismic Energy Release (GCSER) graph
as a function of time, is analyzed in the magnitude domain (discrete energy
windows). Characteristic components of the analyzed graph are: its accelerated
deformation character observed for energy windows lower than the background
seismicity (M = 7.0 - 7.5), its lock state that started on 1923 and long
seismic quiescence periods that preceded recent mega - earthquakes. The
background GCSER value oscillates during the last century with a period of 60
years and with increasing amplitude. The recent (1952 - 2012) 5 mega -
earthquakes are closely related to the amplitude increase of the GCSER
oscillation. Hence, it is suggested that more mega - earthquakes are probable
due to occur in the future. A global mechanism is postulated for the generation
of the mega - earthquakes based on the principles of the non-linearity of the
earth, the Markovitz wobble and the expanding earth. The determination of the
magnitude of the 5 recent mega - earthquakes by the Lithospheric Seismic Energy
Flow Model (LSEFM) method indicates that the latter is globally applicable.
  Key words: Global seismicity, expanding earth, mega - earthquakes, Markowitz
wobble, background seismicity, magnitude determination
