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. Azfz, Azor Fracture Zone; PAFZ: Princess Alice Fracture Zone; PFZ: Pico Fracture Zone

. Fig, Two typical dikes from Sao Miguel island -site 1(Lombo Gordo) Dike Mi3 (image A, left) and Mi7 (image B, right) Both dikes are narrow (width < 1,5 m), with well defined margins and located around 2m -3m above sea level

. Fig, 5 ? Representative curves of normalized (a) isothermal remanent magnetization (IRM) acquisition and (b) back-field IRM demagnetization for samples of São Jorge

. Fig, Left: coercive field versus magnetization plotted on a Day diagram (Day et al., [1977]) showing the dominant pseudo single domain (PSD) magnetic character of most of the samples, However samples from Santa Maria and São Jorge exhibit a single domain magnetic character