| Summary: | In the HOLOCLIP project (Holocene climate variability at high‐southern latitudes: an integrated perspective) the Ross Sea is one of the 4 key areas selected to understand the processes linking different components of the climate system during the Holocene by integrating ice and sediment core data and model simulations. Within the northwestern Ross Sea we propose 3 areas in which it is possible to study the Late Holocene (Neoglacial) to the Hypsithermal period in detail: Joides Basin, and 2 coastal areas, Cape Hallett and Wood Bay. Joides Basin represents an homogeneous sedimentation of structureless diatomaceous mud (about 2 meters thick), Holocene in age, not influenced by coastal glaciers. On the contrary, the two coastal areas show expanded sections of Holocene laminated sediments (seasonal resolution) restricted to time intervals from late Holocene Neoglacial to the Hypsithermal periods influenced by local oceanographic and morphological conditions. In this work we propose a preliminary study on two box cores collected in Cape Hallett and Wood Bay areas during 2005 PNRA oceanographic cruise. Magnetic susceptibility and X ray analyses were performed. Box cores were opened, described and subsampled for 210 Pb, diatoms and foraminifera assemblages, organic carbon, and grain‐size analyses are now in progress. Box core ANTA05‐bc21 was collected in Cape Hallett at a depth of 454 m. It is characterized by a mottled mud with dark olive grey “cotton like” sediment and dark more compact mud. During the sampling, bioturbated sediment with mottles and tube‐worms tests in the topmost 20 cm are recognized. The H2S smell is linked to organic matter reduction. The sediment of the box core ANTA05‐bc40 (Wood Bay area, depth 1034 m) is an olive fluffy mud with wavy black laminae. Some very small carbonate shell is noted. The box cores study will be crucial to link the present to past environmental conditions in the two selected areas.
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