Hillenbrand, Claus-Dieter and Ehrmann, Werner (2002): Distribution of clay minerals in drift sediments on the continental rise west of the Antarctic Peninsula, ODP Leg 178, sites 1095 and 1096

Leg/Site/Hole:
ODP 178
ODP 178 1095
ODP 178 1096
Identifier:
2003-022403
georefid

10.2973/odp.proc.sr.178.224.2001
doi

Creator:
Hillenbrand, Claus-Dieter
Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Federal Republic of Germany
author

Ehrmann, Werner
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, Italy
author

Identification:
Distribution of clay minerals in drift sediments on the continental rise west of the Antarctic Peninsula, ODP Leg 178, sites 1095 and 1096
2002
In: Baker, Peter F. (editor), Camerlenghi, Angelo (editor), Acton, Gary D. (editor), Brachfeld, Stefanie A., Cowan, Ellen A., Daniels, James, Domack, Eugene W., Escutia, Carlota, Evans, Andrew J., Eyles, Nicholas, Guyodo, Yohan J. B., Hatfield, Kate L., Iorio, Marina, Iwai, Masao, Kyte, Frank T., Lauer, Christine, Maldonado, Andres, Moerz, Tobias, Osterman, Lisa E., Pudsey, Carol J., Schuffert, Jeffrey D., Sjunneskog, Charlotte M., Weinheimer, Amy L., Williams, Trevor, Winter, Diane M., Wolf-Welling, Thomas C. W., Ramsay, Anthony T. S. (editor), Proceedings of the Ocean Drilling Program, scientific results, Antarctic glacial history and sea-level change; covering Leg 178 of the cruises of the drilling vessel JOIDES Resolution; Punta Arenas, Chile, to Cape Town, South Africa; sites 1095-1103; 5 February-9 April 1998
Texas A&M University, Ocean Drilling Program, College Station, TX, United States
178
The clay mineral compositions of upper Miocene to Quaternary sediments recovered at Ocean Drilling Program (ODP) Leg 178, Sites 1095 and 1096, from the continental rise west of the Antarctic Peninsula were analyzed in order to reconstruct the Neogene and Quaternary Antarctic paleoclimate and ice dynamics. The clay mineral assemblages are dominated by smectite, illite, and chlorite. Kaolinite occurs only in trace amounts. Analysis of a surface-sample data set facilitates the assignment of these clay minerals to particular source areas on the Antarctic Peninsula and, thus, the reconstruction of transport pathways. In the ODP cores, clay mineral composition cyclically alternates between two end-member assemblages. One assemblage is characterized by <20% smectite and >40% chlorite. The other assemblage has >20% smectite and <40% chlorite. Illite fluctuates between 30% and 50% without a significant affinity to one end-member assemblage. By comparison with a Quaternary sediment sequence from gravity core PS1565, the clay mineral fluctuations can be ascribed to glacial and interglacial periods, respectively. The cyclic changes in the clay mineral composition suggest that glacial-interglacial cycles, repeated ice advances and retreats, and changes in the Antarctic ice volume were already a main control of the global climate in late Miocene time. Throughout the late Neogene and Quaternary, the clay mineral records in the drift sediments exhibit only slight long-term changes predominantly attributed to local changes in glacial erosion and supply of source rocks. The absence of clear long-term trends associated with major climatic or glaciological changes points to an onset of vast glaciation in the Antarctic Peninsula region before approximately 9 Ma and to relative stability of the Antarctic ice sheet since then.
Coverage:Geographic coordinates:
North:-66.5907
West:-78.2916East: -76.5749
South:-67.3401

Stratigraphy; Antarctic ice sheet; Antarctic Ocean; Antarctic Peninsula; Antarctica; Cenozoic; clastic sediments; clay mineralogy; clay minerals; climate change; continental rise; cores; cycles; depositional environment; distribution; drift; erosion; glacial environment; ice; interglacial environment; Leg 178; marine sediments; mineral composition; Miocene; Neogene; Ocean Drilling Program; ocean floors; ODP Site 1095; ODP Site 1096; paleo-oceanography; paleoclimatology; Quaternary; reconstruction; sea ice; sediments; sheet silicates; silicates; Tertiary; upper Miocene;

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