The secular variation of the geomagnetic field in Egypt in the last 5000 years

Abstract

The palaeo-intensities (Fa) of the geomagnetic field in Egypt at some ages are determined by archaeomagnetic measurements and found to be:Fa=36.2 μT at 3100 B.C., Fa=46.8 μT at 3000 B.C.,Fa=36.5 μT at 2780 B.C., 49.0 μT at 2500 B.C., 36.4 μT at 2200 B.C., 57.5 μT at 1990 B.C., 62.1 μT atca 1400 B.C., 61.5 μT at 1400 B.C., 69.9 μT at 600 B.C., 59.3 μT at 550 B.C., 79.9 μT at 460 B.C., 73.7 μT at 450 B.C., 69.7 μT at 320 B.C., 56.2 μT at A.D. 50, 64.9 μT, at A.D. 400, 54.4 μT at A.D. 300, 57.5 μT at A.D. 700 and 43.0 μT at A.D. 1975.