The research presents for the first time a jointly analysis about the impact of the light intermediate Mediterranean (LMW) and dense deep Mediterranean (DMW) bottom currents on the sedimentation in the Alboran Sea (SW Mediterranean) and its paleoceanographic significance in response to climatic oscillations from the last glacial period to the Holocene. For that, an integration of chronostratigraphical, sedimentological, and compositional data from contourites formed by those water masses is carried out. That integration enable us to define three distinct contourite stratigraphic models. (I) The contourite terrace model, characterized by coarse-grained contourites, which is an archive of the interplay between the high-energy Atlantic Water-LMW interface and glacioeustasy from the Younger Dryas to the Holocene. (II) The contourite drift models, which are archives of rapid ocean-climate coupled fluctuations since 29.5 kyr. They comprise coarse-grained contourites formed by a relatively fast LMW and fine-grained contourites formed by a relatively weak DMW, except for the Heinrich Stadials HS3 to HS1 and YD when coarse-grained contourites were deposited. (III) The contourite/turbidite mixed model represents another archive of DMW and glacioeustasy interplay from the end of the late Pleistocene to Holocene.

The age-depth model for core 7 is based on four radiocarbon (14C) dates from well-preserved monospecific samples of planktonic foraminifera (Neogloboquadrina incompta or Globorotalia inflata) measured by accelerator mass spectrometry (AMS) at the Poznan Radiocarbon Laboratory (https://radiocarbon.pl/). Grain-size analysis and distribution were performed using a Coulter LS 100 laser particle size analyser on both the bulk fraction (223 samples) and noncarbonate fraction (465 samples) (http://www.ccit.ub.edu/EN/m6sm2.html). Grain-size statistical parameters were calculated using GRADISTAT software. Geochemical analysis was performed along core 7 with an Avaatech X-ray fluorescence (XRF) core scanner operated at both 10 kV and 30 kV and with a 1 cm sampling interval at Barcelona University (https://www.ub.edu/portal/web/dp-dinamica-terra-ocea/xrf-core-scanner-laboratory).

That contourite stratigraphy allows us to infer for the first time the relative variability of the LMW versus DMW flow regimes, which records differences and similarities. The similarities indicate that the LMW and DMW fluctuations occur in parallel at millennial and centennial time scales. The differences refer to the overall higher velocity of LMW versus DMW; the magnitude changes in velocities that are lower for LMW and higher for DMW; the recognition of three short ventilation events (a, b, c) during HS1 and HS2 for only DMW; and the distinct LMW and DMW responses to the onset of glacial conditions and return to interglacial conditions during the HSs, YD and Holocene cold periods

Tables showing the Oxygen isotope (δ18O) results of cores 7 and C8; the texture, D50, and sorting of bulk fraction from all studied cores and sand percentage, D50, and UP10 percentage of non-carbonate fraction from cores 7 and C8; and the Zr/Rb ratio of cores 7 and C8

With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)

CONTOURIBER (Ref. CTM 2008-06399-C04); FAUCES (CTM2015-65461-C2-1-R)

Peer reviewed