Third Millennium B.C. The Revised Age of Two Hellenic Pyramidal Buildings with a New Nuclear Dating Method

Two small sized squared pyramidal buildings (~14x15m) in Argolid, western Aegean- the Hellenikon and Ligourio- have been studied through the application of physical methods to determine the age of their first construction. The new method of dating developed for this purpose - the Optical Thermoluminescence- has revised their age; around 2500 B.C. instead of the accepted archaeological estimation of 3rd-4th c.B.C. The new method of dating is based on the physical mechanism of bleaching of the thermoluminescence of the surface of carved megalithic limestone blocks as long as they are exposed to sunlight. This bleaching evicts electrons from the electron traps of the carved block and empties these traps. Subsequently, when this megalithic block is placed in the wall and covered by other blocks the exposed surface is no longer seen by sun and the electron traps start to get filled with electrons (via ionization) from the environmental radiation constantly until today. The measurement of the accumulated electrons in such carved surfaces being in firm contact between two megaliths, is a measure of the age since construction. The Optical Thermoluminescence has been tested through,

a) simulation experiments in the laboratory,

b) the dating of well known age buildings in Greece, e.g Mycenean walls, Temple of Apollo in Delphi, and other classical buildings, where the obtained age conforms, within the errors 10-15% at present, with their archaeological age.

The revised ages will be corroborated by new evidence emerged from our multidisciplined project, regarding,

a) more archaeological ceramics of ProtoHelladic II period identified by the archaeologist-excavator,

b) archaeoastronomical orientation relates them with the heliacal rising of Orion constellation, when such star declination occurred only during 2000-2500 B.C.,

c) some hitherto neglected remarks by the original excavators concerning their masonry, and

d) some new interpretation of the legendary report of Pausanias, the flood of Inachos and the return of Danaos from Egypt to Argolid, based upon archaeo-geological and palaeoclimatic data.