Clay minerals in Quaternary marine sediments from the southern Svalbard continental slope: palaeoenvironmental significance.

• Main Authors: Giorgetti G., Lucchi R. G., Macrì P., Sagnotti L., Melis R., Villa G., Colmenero Hidalgo E., Sierro F. J., Barcena M. A., Flores Villarejo J. A., Camerlenghi A., Rebesco M., MORIGI, CATERINA
• Other Authors: Giorgetti, G., Lucchi, R. G., Macrì, P., Sagnotti, L., Melis, R., Morigi, Caterina, Villa, G., Colmenero Hidalgo, E., Sierro, F. J., Barcena, M. A., Flores Villarejo, J. A., Camerlenghi, A., Rebesco, M.
• Format: Conference Object
• Language: English
• Published: AGU 2012
• Subjects: Barents Sea; International Polar Year; IPY; Storfjorden; Svalbard; Spitsbergen
• Online Access: http://hdl.handle.net/11568/242343

Sediment cores have been collected in glaciomarine sequences from the continental slope of the the Storfjorden and Kveithola troughs (south Svalbard), on the northwestern Barents sea continental margin. This sedimentary system was investigated during the SVAIS and EGLACOM cruises both conceived within the International Polar Year (IPY) in 2007-2009. The cores were digitally X-radiographed and scanned for physical properties with a multi-sensor core logger in order to define sediment facies. Detailed palaeostratigraphic investigations together with palaeomagnetic and rock magnetic analyses and AMS dating were used to constrain the age model and for high-resolution inter-core correlation. Sediment samples were analyzed for textural characteristics and clay mineral content in order to define sediment provenance and depositional mechanisms. The clay mineral assemblage is mainly composed by illite (>40%) with chlorite content ranging between 10-40%, kaolinite ranging between 10-30%, and smectite content always minor than 20%. The older sediments consist of a stiff glacigenic diamicton that deposited during last glacial maximum (LGM) and silty clay sediments interbedded with sandy layers deposited during the previous interglacial stage MIS3. The clay mineral assemblage of the glacigenic diamicton contains mainly illite with no traces of smectite. The post-LGM sediment sequence is characterized by an increasing kaolinite and smectite content. Holocene sediments of the mid-slope contain the highest smectite content. The sediments recovered from the Kveithola Trough are characterized by the highest kaolinite and lowest illite content. On average, sediments in cores from the northern Storfjorden slope show higher illite and lower chlorite and kaolinite contents than sediments in cores from the southern Storfjorden and Kveithola slopes. In the northwestern Barents Sea continental margin, illite and chlorite derive from the meta-sedimentary rocks of Spitsbergen, while kaolinite derives from Triassic mudstones and ...