Photo: Timna Valley, where the Egyptians mined ore
By studying the dumps left by a three-thousand-year-old mine, which mined copper by smelting it from iron ore, paleomagnetologists (experts who study the behavior of the Earth's magnetic field in past eras) from the Hebrew University of Jerusalem discovered unusually dramatic changes in the magnetic field of those times
Today it is believed that the earth's magnetic field is created by the movement of streams of molten iron in the earth's core. The field is constantly changing both in structure and in intensity, but the changes occur very slowly and in amplitude do not exceed 16% of the average value. However, about three thousand years ago in Egypt, something extremely strange was happening with this field. Within 180 years, it sharply increased twice (one of the peaks was two and a half times higher than the usual level) and dropped just as sharply, having managed to do this in two decades.
The slag remaining after copper smelting freezes quickly and manages to forever retain the "signature" of the Earth's magnetic field. The mountain of this slag gradually grew, accumulating data on changes in the magnetic field - scientists only had to read this data. Having studied the slag dumps left by the ancient mines of Timna (southern Israel) and Khirbat en-Nahas (northeast Jordan), scientists obtained information about changes in the Earth's magnetic field in the period from 3050 to 2870 years ago. Peaks of extraordinary magnetic activity occurred about 2900 and 2990 years ago.
Geomagnetic peaks did not even come close to resembling what usually happens with the Earth's magnetic field. Not to mention the amplitude, the rate of change was 5-10 times higher than usual. Scientists explain what happened by the rapid movement of small volumes of molten iron in the earth's core just under the place where Israel is now, and formerly Egypt was. This assumption is also confirmed by the fact that in other regions of the planet the magnetic field behaved as usual.