Accretion tectonics of the global seafloor and its evolution

On the basis of the third generation map of the magnetic lineations of the world's ocean basins (Cande et al., 1989), a systematic element division is made for the accretion tectonics of the world's seafloor by use of the con ception of accretion area and accretion period. This work reveals the evolu tion process of the seafloor, which is divided into 49 accretion areas and 6 accretion periods. It is found that the latter accretion processes play r eform roles such as splitting and wedging action to the former. From the vi ewpoint of the whole it seems that the accretion process of the seafloor is characterized by the global episodic synchroneity and strong heterogeneity in spatial distribution as well as the local discontinuity.