Extremely low frequency quasi-static propagation measurements from a calibrated electric field source in the ocean

Experimental data are presented that verify a theoretical model for subsurface-to-subsurface quasi-static propagation from a horizontal electric dipole in a semi-infinite conducting half-space. The data were taken in an ocean environment in a frequency range from 1 to 10 Hz. Horizontal source/sensor separations from 180 to 450 m and depths from 46 to 100 m were used. Comparisons are made between the data and model predictions, relative to range dependence and magnetic field strength. The model predicted magnetic fields were found to agree with the experimentally measured fields approximately within experimental uncertainty.