Heat flow in the Western Mediterranean: Thermal anomalies on the margins, the seafloor and the transfer zones

The Western Mediterranean basin has been formed by Miocene back-arc extension and is underlain by a thin and young lithosphere. This young lithosphere is warm, as testified by an overall elevated offshore heat flow. Heat flow within the Western Mediterranean is, however, highly variable and existing data are unevenly distributed and poorly studied in the central part of the Liguro-Provençal and Algero-Balearic basins. This central part is floored by a young oceanic crust, bordered by different continental margins, cut by transform faults, and filled by up to 8 km of sediments. We present a total of 148 new heat flow data collected during the MedSalt and WestMedFlux cruises in 2015 and 2016 and aligned along seven regional profiles that show an important heat flow variability on the basin-scale, but also locally on the margins. A new heat flow map for the Western Mediterranean outlines the following regional features: (1) a higher average heat flow in the Algero-Balearic basin compared ...