Origin and evolution of the sub-Antarctic islands: the foundation

Abstract

Sub-Antarctic islands have a diversity of origins in detail but most are volcanic and very young suggesting that they are short-lived andthat the distribution would have been very different a few million years ago. Ihey contrast with the common tourist brochure concept ofoceanic islands. As the Antarctic Plate is virtually static, the islands seldom show signs of association with long-lived linear island chains andmost thus stand alone. Longer-lived islands are either on submarine plateaux or are continental remnants of the dispersion of Gondwana.The islands are classified in relation to raised sea-floor, transform fault, triple junction, subduction zone, submarine plateau, submergedcontinent or continental. Many are difficult of access and poorly known geologically. Their geological history controls their many otherroles such as sites as observatories, or for study of colonisation, evolution and speciation rates.