Over The Horizon

Drilling for Success

The international Cape Roberts project has brought up rock cores from deep beneath Antarctica's frozen seas, drilling through 700 metres of strata beneath the sea floor. The layers contain fossils and other features that record the climate from this area of Antarctica from about 20 to -- they think -- 70 million years ago, along with indications of the extent of the Antarctic ice cover during this period.

This season, the project managed a week's drilling before severe storms threatened the 50-tonne drilling platform which sits on two-metre thick sea ice and 150 metres of ocean. Despite the rapid withdrawal of equipment, the multi-million dollar, six-nation project has turned up enough rock to excite the 50 scientists from 28 institutions.

"Last year we had the unexpected discovery of a period several degrees warmer than present, between a million and two million years ago. This time we are hopeful of coring back to the age of dinosaurs, about 65 million years ago," says Chief scientist, Professor Peter Barrett from Victoria University.

"At this time the earth's temperature was around six degrees Celsius warmer than present; a situation we may find ourselves in again in a few hundred years with increases in CO₂ and other greenhouse gases. One of the things we want to know is to what extent these higher temperatures in the past have melted ice sheets and raised sea levels," Barrett says.