In geomantic omen, what are the positive and negative magnetic fields? Why do some dead animals die together, and it is easy to attract some unclean things? Why a negative magnetic field?

This is mainly due to the local magnetic field of the earth. The wavelength, frequency and intensity of magnetic field will affect some lower organisms. For example, when a person goes to a strange valley, he will be instinctively afraid. This is your subconscious fear of the unknown, not a magnetic field. The magnetic field will disturb your mood at most, but it won't make you afraid. The so-called unclean things should be the haunted "hutcheson effect". You can refer to the answer in the encyclopedia.