Knut Heinatz¹, Lavenia Ratnarajah², Kerrie Swadling¹, Scott Meyerink¹, Ashley T Townsend³ and Andrew R Bowie¹, (1)University of Tasmania, Institute for Marine and Antarctic Studies, Hobart, TAS, Australia, (2)University College London, Department of Earth Sciences, London, United Kingdom, (3)University of Tasmania, Central Science Laboratory, Hobart, TAS, Australia