A general procedure to evaluate the electromagnetic fields generated by moving seawater through the geomagnetic field is proposed. It contains two essential steps: modeling of velocity vector of seawater according to its dynamic mechanism, and solution of Maxwell equations under a stratified ocean configuration. Two kinds of motions are considered in this work, wind-driven waves and wakes due to a moving body. The ocean is taken to be infinitely deep at the moment. Both the velocity vector and magnetic field are expressed as a superposition of sinusoidal waves. Simulation results show that the magnetic fields produced by moderate wind waves or a middle-size body moving at moderate speed are on the order of one hundred pico-Tesla near the sea level. The spectrum characteristics of the two kind magnetic anomalies are distinct.
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