Holocene calcareous nannofossils and planktonic foraminifera assemblages in the western Magellan Strait (Chile)

• Main Authors: F. O. Amore, CAFFAU, MAURO, COLIZZA, ESTER, SALVI, Gianguido, TSAKIRIDOU, ERIKA
• Other Authors: "International Nannoplankton Association", F. O., Amore, Caffau, Mauro, Colizza, Ester, Salvi, Gianguido, Tsakiridou, Erika
• Format: Conference Object
• Language: English
• Published: Senckenbergische Naturforschende Gesellschaft 2003
• Subjects: nannoplankton; INA; Antarctic; Pacific; Antarc*; Antartide; Planktonic foraminifera
• Online Access: http://hdl.handle.net/11368/2729693

INA8 8th International Nannoplankton Association Conference ABSTRACTS [Abstracts] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z] Filomena O. Amore, Mauro Caffau, Ester Colizza, Gianguido Salvi, Erika Tsakiridou: Holocene calcareous nannofossils and planktonic foraminifera assemblages in the Western Magellan Strait (Chile) (Poster) Two gravity cores, MB91/40 (53°04'S, 73°33'W; 451cm long) and MB91/54R (53°25'S, 72°54'W; 458.5cm long), have been recovered in the deeper and more inner basinal zone of the Western Magellan Strait in the framework of the marine geological research of the Programma Nazionale di Ricerche in Antartide. This work plans to identify the Late Quaternary changes through micropalaeontological data together with sedimentological data and their link to the climatic cycles. In particular, it highlights the value of the coccolithophore assemblages, never analysed before in the Strait of Magellan, and planktonic foraminifera in identifying the palaeoenvironmental and palaeoceanographic characteristics that influenced this area during the Holocene climatic evolution. The western sector of the Strait of Magellan is set up on a transform fault (Magellan Fault), mostly WNW-ESE oriented. A stratified and stable structure of the water-masses characterises this sector, where a colder and more dilute surficial water-mass overlies a deeper, warmer and saltier one. The deeper water-mass testifies to the Pacific influence and the inflow of sub-Antarctic water in this sector of the Strait. The cold, low-salinity surface-waters testify to the influence of continental runoff due to glaciofluvial input (Panella et al., 1991). In the western Magellan Strait, the surficial sediments are characterised by sand, silty sand, carbonate and biogenic carbonate in the threshold zone, whilst the processes of fine sedimentation of carbonate material compounded with terrigenous sediment dominate in the inner part of the Pacific branch (Brambati et al., 1994). The ...