The Galicia Interior Basin (GIB; NW Iberian Peninsula) is located near a critical transition between the subtropical (temperate) and subpolar (cold) gyres of the North Atlantic. It therefore witnesses oceanographic changes driven by global climatic events. This study reports on the recent (latest Pleistocene) sedimentary, palaeoceanographic and palaeoclimatic history of the basin. We integrated analysis of deep‐sea sediment cores retrieved from an E–W transect across the GIB. The analysis indicated three types of sedimentary processes recording glacial (Marine Isotope Stage 2–4) and deglacial events: along‐slope bottom currents (forming contourite deposits), pelagic and hemipelagic sedimentation, and gravitational dislocation. Variation in depositional patterns and sedimentation rates indicate distinctive transport (along‐slope and down‐slope) and depositional processes. These in turn reflect climatic and oceanographic drivers. We interpret changes in sea level from core evidence showing changes in sediment supply. The cores exhibited conspicuous sedimentary evidence of Heinrich events (HEs). The stratigraphic intervals associated with HEs showed significant lateral variation. We suggest that the lateral variation may result from the development of an oceanographic boundary between surface water masses with different temperature and salinity parameters or changes in surface currents which may have introduced relatively warmer water into the GIB during the last glacial period.

Outer shelf sedimentary records are promising for determining the recurrence intervals of tsunamis. However, compared to onshore deposits, offshore deposits are more difficult to access, and so far, studies of outer shelf tsunami deposits are scarce. Here, an example of studying these deposits is presented to infer implications for tsunami-related signatures in similar environments and potentially contribute to pre-historic tsunami event detections. A multidisciplinary approach was performed to detect the sedimentary imprints left by the 1755 CE tsunami in two cores, located in the southern Portuguese continental shelf at water depths of 58 and 91 m. Age models based on ¹⁴C and ²¹⁰Pb_xs allowed a probable correspondence with the 1755 CE tsunami event. A multi-proxy approach, including sand composition, grain-size, inorganic geochemistry, magnetic susceptibility, and microtextural features on quartz grain surfaces, yielded evidence for a tsunami depositional signature, although only a subtle terrestrial signal is present. A low contribution of terrestrial material to outer shelf tsunami deposits calls for methodologies that reveal sedimentary structures linked to tsunami event hydrodynamics. Finally, a change in general sedimentation after the tsunami event might have influenced the signature of the 1755 CE tsunami in the outer shelf environment.