Linda Balfoort

Contact

Phone: 0210 228 4763
Email: linda.balfoort@vuw.ac.nz
Office: CO421

Qualifications

BSc Victoria University of Wellington (2020)
MSc Candidate in Sedimentology and Palaeoclimatology

Master thesis

Title

Sedimentation in a sub-ice shelf channel.

Supervisors

• Dr Gavin Dunbar
• A/Prof Huw Horgan
• Dr Sebastian Naeher (GNS Science)

Project objectives and description

Very few observations exist from underneath Antarctica’s largest ice shelves due to their remoteness and immense ice thickness. The Ross Ice Shelf is the largest ice shelf in the world, but sediments cores have only been collected at a handful of sites. The Kamb Ice Stream (KIS) is part of a series of ice streams that flow west off the West Antarctic Ice Sheet and combine to form the eastern Ross Ice Shelf and together they account for ~40% of West Antarctic Ice Sheet mass loss. Ice flow fluctuations of these ice streams exert a significant influence on West Antarctic Ice Sheet mass balance.

Preliminary observations of the water column and sea floor (collected during 2021/2022 austral summer) at the Kamb Ice Stream (KIS) 2, Ross Sea, Antarctica show it represents a very different environment to KIS-1, ~50 km away (and HWD-2, central Ross Sea). Notably the suspended sediment (‘floc’) concentration is much higher and the aquatic biota (fish and crustaceans) are much more abundant. This doesn’t appear to correspond to a thick accumulation of sediment on the seafloor, however. Using a three-part approach, I am hoping to understand and compare the depositional environment at KIS-2. First, I will examine the organic molecules (biomarkers) present in the sediment to compare it with those found elsewhere in the Ross Sea – how different is this ecosystem?; second, I will calculate the concentration and settling flux of water column particulates to estimate how much sediment is ‘exported’ from the channel to the open sea and third, I will examine the microfossil and lithological composition of the sediment to determine its provenance and how this relates to regional glaciology.