A CHRONOLOGY FOR THE DOME-C DEEP ICE-CORE SITE THROUGH RADIO-ECHO LAYER CORRELATION WITH THE VOSTOK ICE CORE, ANTARCTICA

Ice at the new Dome C drill site is correlated directly with the Vosto k ice-core record using internal radio-echo layering in the Antarctic Ice Sheet. Layering observed on 60 MHz radar records at ice depths gre ater than 1000 m is a result of electro-magnetic wave reflections from acidic ice layers formed, it is assumed, by volcanic eruption-derived aerosols. These acidic layers represent isochronous surfaces within t he ice sheet. We are able to trace five prominent layers for over 500 km across the Antarctic Ice Sheet, between Vostok and the new ice-core site at Dome C. This correlates the stratigraphy and depth-age relati onship between the two sites. The thickness of ice deposited over the last glacial cycle (120,000 years) at Dome C is 300 m greater than at Vostok and, at comparable depths, the ice at Dome C is between about 1 0,000 and 25,000 years younger than at Vostok.