Geomagnetic induction surveys have indicated the presence of several areas where electrical resistivity in the continental crust is abnormally low. Several such anomalies occur either along present continental margins or over postulated aulacogens (failed rifts), where the low resistivities cannot be explained by elevated temperatures. This implies a close association between the site of anomalies and former plate boundaries, areas where buried ocean crust might occur in the present continental crust. It is suggested that the low inferred resistivities might arise from the presence of such buried hydrated ocean crust. A resistivity profile model for a layer of ocean crust embedded in continental crust is developed, and a number of induction anomalies which might be explained by the model are discussed.

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