Preliminary stratigraphy of volcanoes in the Executive Committee Range, central Marie Byrd Land

Extract

Marie Byrd Land is amongst the most inaccessible and least visited regions of Antarctica. It contains a large alkaline volcanic province, with 18 large central volcanoes and numerous small satellitic centres, ranging in age from late Oligocene (c. 28–30 Ma) to Recent (LeMasurier 1990). The volcanic rocks provide an outstanding record of the late Cenozoic glacial and volcanic history of Antarctica. The volcanism has been described within a region-wide model of hot-spot impingent at the base of the crust, widespread eruption of mafic plateau lavas and the sequential release of more evolved magmas from crustal chambers beneath central volcanoes situated along a series of reactivated, orthogonal basement fractures (LeMasurier & Rex 1989). Most of the volcanoes have been studied only on a reconnaissance level.