Open AccessTransient electromagnetic responses in seafloor with triaxial anisotropy
Author(s) -
Yu L.,
Evans R. L.,
Edwards R. N.
Publication year - 1997
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1997.tb01582.x
Subject(s) - anisotropy , seafloor spreading , geology , transient (computer programming) , dipole , geophysics , ridge , electrical conductor , crust , magnetotellurics , mid ocean ridge , electrical resistivity and conductivity , physics , optics , paleontology , quantum mechanics , computer science , operating system
Summary Electrical anisotropy of young oceanic crust at mid‐ocean ridges is detectable by observation of the rate and geometry of the diffusion of electromagnetic fields. The anisotropy in electrical properties arises from the presence of conductive seawater in an interconnected network of mostly ridge‐parallel cracks. In this paper, we first justify the choice of a triaxial model to represent young oceanic crust, with three distinct electrical conductivities in the vertical, strike and spreading directions. We then present an algorithm to calculate the transient electromagnetic responses generated by an electric dipole source over such a triaxially anisotropic seafloor. We show that if the transient passages are measured with three distinct electric dipole‐dipole configurations, it is possible to discern all three unknown conductivities independently of each other.