Geomagnetic secular variations in Greece through the last 6000 years obtained from lake sediment studies

Summary. Geomagnetic declination and inclination secular variation curves have been constructed back to 6000 yr BP from palaeomagnetic measurements of sediments cored in Lakes Volvi, Trikhonis and Begoritis, Greece. They have been dated by palynological studies and by comparison with observatory and archaeomagnetic records. Radiocarbon ages are all affected by the ‘old carbon’ factor. Cores from all three lakes contain a thin ash layer which we associate with the Pompeii eruption of Vesuvius in AD 79. Averaged curves of secular variations of declination and inclination have been computed for the whole study. The broader scale pattern of secular variations is basically similar to lake sediment records from the UK, Poland and Switzerland, though finer detail in the structure of some of the principal features is resolved.