QUATERNARY GLACIATIONS IN THE SOUTHERN-OCEAN - SECTOR 0-DEGREES LONG - 180-DEGREES LONG

Isolated islands in the Southern Ocean east of 0° longitude are all of volcanic origin. As some were active both volcanically and tectonically during the Quaternary, glacial features may be masked and confused by lava flows and faulting. The location of the islands close to the Antarctic Convergence is potentially important for studying fluctuations in its position; northward migration cools the islands and causes glacier expansion. Intercalation of glacial sediments and lava flows on Marion, Kerguelan and Heard Islands provides some evidence of glacier fluctuations during the Mid-Late Quaternary, but much of the data are equivocal. The most detailed dated Quaternary record is from Marion Island where the oldest glaciation (stage 8) had five stadials, the penultimate glaciation (stage 6) had three stadials, and the last glaciation had ended by 12 ka BP. Glacier expansion is closely related to northward migration of the Antarctic Convergence, when lower temperature converts the high rainfall into snowfall. © 1990.