Curie Point Depth of the Island of Crete (Greece)

The aeromagnetic data of the island of Crete were inverted to produce Curie point estimates. The data were high-pass filtered to remove components arising from topography and magnetic core fields which were not adequately modeled by IGRF. The depth to the centroid, z0, of the deepest distribution of the magnetic dipoles, was obtained by computing a least-squares fit to the lowest-frequency segment of the azimuthally averaged log power spectrum. The depth to the top of the deepest crustal block was computed as the depth, zt, to the centroid of the second deepest distribution, using the second lowest-frequency segment of the spectrum. The depth to the bottom of the deepest dipoles, the inferred Curie point depth, is then zb 2z0 zt. The Curie depth estimates range between 24 and 28 km. This is in accordance with the depths inferred by extrapolating heat-flow values measured in boreholes.