• journal_title：Geology
• Contributor：Nabil Khélifi ; Michael Sarnthein ; Nils Andersen ; Thomas Blanz ; Martin Frank ; Dieter Garbe-Schönberg ; Brian A. Haley ; Roland Stumpf ; Mara Weinelt
• Publisher：Geological Society of America
• Date：2009-
• Format：text/html
• Language：en
• Identifier：10.1130/G30058A.1
• journal_abbrev：Geology
• issn：0091-7613
• volume：37
• issue：9
• firstpage：811
• section：Articles

d="p-1">Largely continuous millennial-scale records of benthic δ¹⁸O, Mg/Ca-based temperature, and salinity variations in bottom waters were obtained from Deep Sea Drilling Project (DSDP) Site 548 (East Atlantic continental margin near Ireland, 1250 m water depth) for the period 3.7–3.0 Ma ago. High ε_Nd values of −10.7 to −9 show that this site monitored changes in Mediterranean Outflow Water (MOW) throughout the mid-Pliocene. Bottom water variability at Ocean Drilling Progam (ODP) Site 978 (Alboran Sea, 1930 m water depth) provides a complementary record of MOW composition near its West Mediterranean source. Both sites show a singular and persistent rise in bottom water salinities by 0.7–1.4 psu, and in densities by ~1 kg m⁻³ from 3.5 to 3.3 Ma ago, which is matched by an ~3 °C increase in bottom water temperature at Site 548. This event suggests the onset of strongly enhanced deep-water convection in the Mediterranean Sea and a related increase in MOW flow as a result of major aridification in the Mediterranean source region. In harmony with model suggestions, the enhanced MOW flow has possibly intensified Upper North Atlantic Deep Water formation.