Expedition GEA II (2011/2012)
Report of the project:
The follow-up expedition GEA II was carried out in the Antarctic season 2011/12 by BGR again in cooperation with the AWI and BELARE. Additionally, the universities of Bergen (Norway), Bremen (Germany) and Durban (South Africa) were involved. The main target of the eight-weeks expedition was again Sør Rondane in eastern Dronning Maud Land.
Working area GEA II
Source: BGR
The inbound transport to Antarctica took place shortly before Christmas 2011 from Cape Town to Novolazarevskaya and from there onwards with a Basler DC-3 to Princess Elisabeth Station in Sør Rondane. The research programme included an aerogeophysical survey - using AWI's research aircraft "Polar 6" as platform - and a more extensive skidoo and helicopter-supported geological and ground-based geophysical field work. Planning of the science programme was based on the results of the expedition GEA I in the previous season. In addition, the scientists were able to reach the southeastern nunataks of Sør Rondane and several previously unvisited nunataks in the Borchgrevinkisen to the west of Sør Rondane and the southeastern nunataks and moraines in central Dronning Maud Land south of Novolazarevskaya.
The Belgian station "Princess Elisabeth" in Sør Rondane. In the foreground the magnetic base station for the flight
Source: BGR
The field work was carried out from Princess Elisabeth station and Novolazarevskaya. A base camp for the aerogeopysical survey was set up at Crown Bay on the Antarctic coast, which was in an approximately distance of 200 km from Princess Elisabeth station. Besides geophysics, main focus was on structural geology and petrology and thermochronological investigations, e.g. the fission track dating method on the mineral apatite. This method is usually used for the determination of low-temperature, near-surface and landscape-forming processes, such as the uplift of rocks within the earth's crust or the removal of superimposed rocks as a result of erosion. In particular, it provides an indication of the development of the pre-glacial landscape evolution since the breakup of Gondwana. An unexpected finding were large gypsum crystals that formed at the interface between ice and glacial debris at the southernmost glacial moraine in front of the Sør Rondane ice plateau. The origin of these crystals, how they could grow under these special conditions and what significance they have was of particular interest.