Calcareous plankton response to orbital and millennial-scale climate changes across the middle Pleistocene in the western Mediterranean

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doi: 10.1016/j.palaeo.2013.09.005
Author(s): Girone, Angela; Maiorano, Patrizia; Marino, Maria; Kucera, Michal
Author Affiliation(s): Primary:
Universita degli Studi di Bari Aldo Moro, Dipartimento di Scienze della Terra e Geoambientali, Bari, Italy
Universität Bremen, Fachbereich Geowissenschaften, Germany
Volume Title: Palaeogeography, Palaeoclimatology, Palaeoecology
Source: Palaeogeography, Palaeoclimatology, Palaeoecology, Vol.392, p.105-116. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0031-0182 CODEN: PPPYAB
Note: In English. 155 refs.; illus., incl. charts, sketch map
Summary: The paleoenvironmental conditions through MIS 15-9 at the Mediterranean Ocean Drilling Program (ODP) Site 975 were interpreted by high resolution study of calcareous plankton assemblages compared with available δ18O and δ13C records and high resolution paleoclimate proxies from the Atlantic Ocean. Sea Surface Temperatures (SSTs) have been estimated from planktonic foraminiferal assemblages using the artificial neural networks method. Calcareous plankton varied dominantly on a glacial-interglacial scale as testified by the SST record, foraminiferal diversity, total coccolith abundance and changes in warm-water calcareous nannofossil taxa. A general increase in foraminiferal diversity and of total coccolith abundance is observed during interglacials. Warmest SSTs are reached during MIS 11, while MIS 12 and MIS 10 represent the coldest intervals of the studied record. During MIS 12, one of the most extreme glacials of the last million years, occurrence of Globorotalia inflata and of neogloboquadrinids indicates a shoaling of the interface between Atlantic inflowing and Mediterranean outflowing waters. Among calcareous nannofossils the distribution of Gephyrocapsa margereli-Gephyrocapsa muellerae > 4µm also supports a reduced Atlantic-Mediterranean exchange during MIS 12. Superimposed on glacial-interglacial variability, six short-term coolings are recognized during MIS 12 and 10, which appear comparable in their distribution and amplitude to the Heinrich-type events documented in the Atlantic Ocean in the same interval. During these H-type events, Neogloboquadrina pachyderma (s) and G. margereli-G. muellerae > 4µm increase as a response to the enhanced inflow of cold Atlantic water into the Mediterranean via the Strait of Gibraltar. Mediterranean surface water hydrography appears to have been most severely affected at Termination V during the H-type event Ht4, possibly as a response to a large volume of Atlantic meltwater inflow via the Strait of Gibraltar and/or to freshwater/terrigenous input deriving from local mountain glaciers. Three additional SST coolings are recorded through MIS 14-16, but these are not well correlated with Heinrich-type events documented in the Atlantic Ocean in the same interval; during these cooling episodes only the subpolar Turborotalita quinqueloba increases. These results highlight the sensitive response of the Mediterranean basin to millennial-scale climate variations related to Northern Hemisphere ice-sheet instability and support the hypothesis that the tight connection between high latitude climate dynamics and Mediterranean sea surface water features can be traced through the Middle Pleistocene. Abstract Copyright (2013) Elsevier, B.V.
Year of Publication: 2013
Research Program: IODP Integrated Ocean Drilling Program
ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Algae; Atlantic Ocean; Balearic Basin; Biodiversity; Calcareous composition; Cenozoic; Climate change; Coccolithophoraceae; Expedition 306; Expeditions 303/306; Foraminifera; Gephyrocapsa; Glacial environment; Globigerina; Globigerina bulloides; Globigerinacea; Globigerinidae; Globorotalia; Globorotalia inflata; Globorotaliidae; Heinrich events; IODP Site U1313; Integrated Ocean Drilling Program; Invertebrata; Isotope ratios; Isotopes; Leg 161; MIS 10; MIS 11; MIS 12; MIS 15; Mediterranean Sea; Microfossils; Mid-Atlantic Ridge; Middle Pleistocene; Minorca Rise; Nannofossils; North Atlantic; Northeast Atlantic; O-18/O-16; ODP Site 975; Ocean Drilling Program; Oxygen; Paleoclimatology; Paleoenvironment; Paleotemperature; Plankton; Planktonic taxa; Plantae; Pleistocene; Protista; Quaternary; Rotaliina; Stable isotopes; West Mediterranean
Coordinates: N383000 N393000 W0100000 W0150000
N410000 N410000 W0325700 W0325700
N385348 N385348 E0043036 E0043036
Record ID: 2014016549
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands