Electromagnetic frequency sounding method for measuring vertical magnetic field and vertical gradient thereof

The invention discloses an electromagnetic frequency sounding method for measuring a vertical magnetic field and a vertical gradient of the vertical magnetic field, belongs to the field of geological exploration, and solves the problems that an existing electromagnetic frequency sounding method needs to observe an electric field, and the accuracy of an observation result is poor due to the poor grounding condition of an exploration area or the influence of a static effect. The method comprises the following steps: arranging two single-component fluxgate sensors up and down at an interval, and measuring a vertical magnetic field and a vertical gradient thereof; the two single-component fluxgate sensors are respectively connected to a data collector, the data collector is provided with a plurality of sampling frequencies, and vertical magnetic field components sensed by the single-component fluxgate sensors are recorded as a time sequence and stored; a power spectrum estimation algorithm is used for obtaining p