The Geological History of Cenozoic Polar Oceans: Arctic Versus Antarctic — an Introduction

Abstract

Throughout geological history, the Earth has repeatedly experienced the developmqent of cold climates which led to extensive glaciation of the polar regions (Frakes, 1979; Schwarzbach, 1974). During most of these ‘glacial’ episodes, plate tectonics — or was it pure coincidence? — placed a large and therefore elevated land mass (Hay et al., 1981) at one or the other of the poles. These polar continents were subsequently covered by ice-sheets, the geological evidence for which has been well documented. At the same time, the opposite pole was situated in the open ocean, from where no data have been preserved. For the latter we can only assume that it was not ice-covered because of the potentially rapid advection of temperate water masses from lower latitudes. These older, pre-Cenozoic glaciations were, therefore, unipolar, and probably resulted in much more important climatic asymmetries than we observe today, or have experienced in the recent past.