Tracing Antarctic Bottom Water formation in the Adélie and George V Land: A proxy calibration study.

Add to your list(s) Download to your calendar using vCal

• Taryn Noble (Tasmania)
• Tuesday 06 September 2016, 14:00-15:00
• Harker 1, Department of Earth Sciences, Downing Street.

If you have a question about this talk, please contact Andy Buckley.

Antarctic Bottom Water (AABW) is one of the most important water masses in the global ocean. These cold dense waters form the lower limb of global thermohaline circulation system and ventilate the abyssal ocean. Understanding the consequences of variable AABW formation during different climate regimes requires the extraction of reliable proxy data from marine sediment archives. However, sediments around the Antarctic margin are challenging to work with due to the nature of the sediment (diatom ooze, glacial-eroded sediments) and range of depositional environments. In this study, we examine a suite of surface sediments and associated oceanographic data on the Adélie and George V Land (AGVL) shelf, East Antarctic, proximal to the Mertz polyna, where high salinity shelf waters cascade down the slope to form about a quarter of the global AABW . A series of different chemical extractions were performed, including the separation of diatoms from the bulk sediments, to isolate the authigenic Nd isotopic signature of this AABW end-member. We also evaluate the use of redox sensitive metals to characterise bottom water ventilation. This calibration study will inform the study of marine sediment cores collected on the AGVL slope, which will be used to test the role of ocean forcing on Antarctic ice shelf instability.

This talk is part of the Occasional Earth Science Seminars series.

This talk is included in these lists:

• Harker 1, Department of Earth Sciences, Downing Street
• Department of Earth Sciences seminars

Note that ex-directory lists are not shown.