Sub-EIS-Obs III – Studies and geoscientific observations beneath the Ekström Ice Shelf
Report of the project:
The geoscientific expedition „Sub-EIS-Obs III“ took place from November 2018 to January 2019 on the Ekström Ice Shelf west of the AWI station “Neumayer III”.
Working area Sub-EIS-Obs
Source: BGR
Hot water drilling with the first, thin lance
Source: BGR
For planning of this third Sub-EIS-Obs season, the information from the previous seismic campaigns was used to find additional potential drilling locations, which would give further information about the uppermost sediment layers beneath the ice shelf. As for “Sub-EIS-Obs II”, a 30-40 cm wide hole was drilled in the ice shelf using the hot water drilling system. The thickness of the ice shelf was between 210 and 330 m. To get samples from the uppermost sediment layers, different devices were used: Wippermann grabber, gravity corer, UWITEC percussion driller and a vibro corer, which was provided by the Chinese participants. In preparation of the expedition, the devices and their application were renewed and optimised based on previous experiences during “Sub-EIS-Obs II”. Before each drilling, a camera in a pressure housing and a torch were sent down to get images and videos of the surface of the ocean floor and the bottom side of the ice shelf. Additionally, a conductivity-temperature-depth measurement device was attached to the rope to generate data during each drilling activity.
In total, five drilling localities were finished during this campaign, which resulted in 11 drill cores between 27 and 198 cm length and several disturbed sediment samples from the surface. The sample material will be jointly analysed by BGR and AWI.