| Abstract | This contribution integrates and analyzes data from high-resolution multibeam, seismic profiles, bathymetric
LiDAR, and surficial sediment data for the geomorphological seascapes characterisation and processdescription
of the Basque inner and middle continental shelf (northern Spain). From the data obtained, the
Basque shelf is characterised by a heterogeneous seafloor where, on a small spatial scale, different
morphologies and sedimentary processes can be observed. Tectonic activity and sea-level changes, together
with present processes of sediment supply and climatic conditions, have a critical influence on the present
configuration of the continental shelf and the distribution of seafloor types. On the basis of all of the datasets,
seafloor classification, bedform analysis, long-term sea-level change-induced seafloor features and
anthropogenic features over the seafloor, are described. As a result, three distinct zones have been identified
for the Basque shelf, related to the main geomorphological features and seascapes, as summarised below. (i)
A western part, with a northwestern orientation, which coincides with the prevailing wave direction. This
zone is characterised by a predominantly rocky substrate, except within the mouth of the Nervión estuary,
where sandy sediments appear to infill a paleo-channel. (ii) A central part, which is oriented towards the
northeast and receives less wave energy. Within this zone, a sedimentary seabed is predominant. Sorted
bedforms are well developed and can be detected in water depths in excess of 90 m. (iii) An eastern zone,
which is characterised by sedimentary seafloor and shore terraces; here, a flat rocky seafloor is covered by a
thin layer of sediments. Throughout the study area, the bathymetry and sedimentary features of the
shoreface and inner shelf are controlled mainly by climatic conditions, coastal dynamics and the underlying
geological framework. The integration of these data sets, together with their interpretation, is a valuable
source of information for Integrated Coastal Zone Management (ICZM) and constitutes a useful tool for
implementing various European Directives.
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