Matrix Methods for Joint Interpretation of Two-dimensional Gravity and Magnetic Anomalies with Application to the Iceland-Faeroe Ridge

Gravity and magnetic anomalies caused by a body satisfying the Poisson condition can be inter-related by linear algebra through use of a fictitious equivalent layer. Computer programs using this formulation have been written to carry out two-dimensional pseudogravimetric and pseudomagnetic transformations, to estimate the direction of magnetization, and to compute the ratio of magnetization to density within an assumed equivalent layer. The method is applicable to other problems of direct interpretation of gravity and magnetic anomalies and can be extended to three-dimensional interpretation. It is amenable to irregularly spaced field data. The methods have been used to show that the complicated magnetic anomalies over the Iceland-Faeroe Ridge are partially related to the gravity anomalies. The correlation is attributed to substantial variations in the depth to the layer 1/layer 2 interface.