Documentation of sediment cores ...

• Main Authors: Graham, Alastair G C, Larter, Robert D, Gohl, Karsten, Hillenbrand, Claus-Dieter, Smith, James A, Kuhn, Gerhard
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2009
• Subjects: Gravity corer; Giant box corer; ANT-XXIII/4; Polarstern; Paleoenvironmental Reconstructions from Marine Sediments @ AWI AWI_Paleo; Amundsen Sea; Antarc*; Antarctica; West Antarctica
• Online Access: https://dx.doi.org/10.1594/pangaea.724192; https://doi.pangaea.de/10.1594/PANGAEA.724192

The presence of a complex bedform arrangement on the sea-floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-temporal record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single down-flow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the mid-to-outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal-ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the ...