Oct 7 (): Scientists have claimed to have found the world’s oldest ice sheet in eastern Antarctic region, which they say may date back 1.5 million years.
The discovery has been made by scientists from 22 countries. They concluded the findings after five years of research. The team of scientists, including Dr Tas van Ommen from the Hobart-based Australian Antarctic Division, say they have found the most likely place of ice dating from 1.5 million years ago, almost double the oldest ice cores so far taken out, at 800,000 years.
Dr Tas van Ommen says airborne radars were used to shine light through the ice and reveal its thickness. He said, “There are large areas of east Antarctica where we really didn’t know anything about the ice thickness or at least very little. There were big voids in the coverage”.
The team under the cooperative project between the UK and the US using old DC-3 aircraft flew out of Casey station and mapped bedrock underneath ice over a very large area called Aurora Basin.
They then used information they had got from existing ice cores, estimates of the heat coming up from the earth, the geothermal heat, and then some of the team members ran very detailed models of how the ice flows would look and how old the ice would be. The scientists had found the ice sheet is about three kilometres thick.
Dr van Ommen says an ice core taken from the sheet could hold valuable information about the earth’s climate and greenhouse gases.
Using tried and tested techniques, the scientists plan to drill deep into the shelf to access the oldest layers of ice. The deep drilling project in Antarctica could start within three to five years to reach the 1.5 million-year-old sample that would permit scientists to analyse those levels. The drills will need to extract a 2.4 – 3.2 kilometre-long (1.5 – 2 mile) ice core from the region.