Characterizing the Source of the Eastern Galicia Magnetic Anomaly (NW Spain): The Role of Extension in the Origin of Magnetization at the Central Iberian Arc

The Eastern Galicia Magnetic Anomaly is the best studied anomaly of Central Iberian Arc. This due to its location, on Lugo-Sanabria gneiss dome, and fact that source rocks crop out in Xistral Tectonic Window. Multiple studies this have been carried out, but still, new results keep shedding light understanding. paper presents first rock magnetic analyses, natural remanent magnetization, anisotropy susceptibility, X-ray diffraction, stable isotopes geochemistry anomaly. Results suggest magnetization responds increase oxygen fugacity underwent by affected late Variscan (330-300 Ma) extensional tectonics. Extensional detachments were pathways allowed entrance fluids led syntectonic crystallization magnetite hematite metasediments inhomogeneous S-Type granitoids derived from their partial melting. Accordingly, not linked lithologies, structures developed Carboniferous/earliest Permian, during Kiaman reverse superchron. Systematic remanence exhibited hematite-bearing samples confirms age adds complexity interpretation Understanding EGMA contributes other anomalies existing CIA, also located thermal domes. observed extension-related probably most NW Massif, thus hindering study previous tectonics paleomagnetic techniques. work aims provide hints interpret tectonic contexts worldwide.