Last deglacial reorganization of the western Mediterranean thermohaline circulation: evidences from sedimentological and Nd isotopes proxies

Abstract

Last glacial/interglacial transition involved significant changes in western Mediterranean (Med) thermohaline circulation that culminated with the formation of an organic rich layer (ORL) in the Alboran Sea from 14.5 to 9 ka BP. This event pre-dated the eastern Med stagnation associated with the Last Sapropel (S1: 10.8-7.1 kyr BP). Here we aim to gain in the understanding that those two events had in the oceanography of the westernmost Med and ultimately its impact on the Med outflow waters (MOW). Our approach combines sedimentological indicators (grain-size and XRF-core scanner data) with Nd isotopes measured in foraminifera diagenetic coatings as a proxy of water mass source. The studied material includes a set of cores covering a depth range from the Alboran Sea (from 300 to 1800 m) combined with a core from the Balearic Basin and another from the Gulf of Cadiz...