Geophysical identification of permafrost in Antarctica

CLIENT

Uruguayan Antarctic Institute (IAU) is a governmental agency managed by the Departments of National Defence, Foreign Affairs, and Education, responsible for organizing and developing operational, logistical, and research activities in the Antarctic region.

CHALLENGE

Some of the foundations of the Antarctic scientific bases on King George Island are anchored directly on the permafrost.
With increasing global temperatures and the associated risk of permafrost melting, the stability of the island’s infrastructure could be in jeopardy as the frozen zone contracts. The objective of the geophysical survey was to characterize the depth of the permafrost layer and identify any localized melt zones.

 

SOLUTION

The resistivity meter ABEM Terrameter LS was used for a three-dimensional (3D) acquisition of resistivity values, with an 8×5 grid with 10-m electrode spacing and a gradient-type array.

RESULT

The results clearly show the presence of high resistivity values (6000 – 9000 Ohm-m) that are associated with the permafrost layer at an average depth of 7 meters. The result is consistent with the information reported from test-drillings at nearby bases. As an outcome, the geophysical identification of permafrost in Antarctica using the resistivity meter ABEM Terrameter LS was deemed a success.

Antarctica – Permafrost case (PDF)