Phanerozoic Paleocontinental World Maps

The presentation of a revised set of maps for the Mesozoic and Cenozoic, together with a new set for the Palaeozoic, provides a useful framework on which researchers, teachers and students can plot any data of their choice. The maps show the outlines of the modern con-tinents situated as they may have been at 22 periods of time from the Present back to the early Cambrian, and are accompanied by nine pages of text explaining the methods of construction. As the authors make clear, the Mesozoic and Cenozoic maps are constructed on a much firmer basis than that for the Palaeozoic. There is now little uncertainty as to the position of the major continents from the Jurassic onwards; ocean floor magnetic anomalies supported by palaeomagnetic data from the continents provide a reasonable foundation for determining continental positions. The authors, however, do not discuss the positions of many small continental fragments, such as the small plates in the MediterraneadTethys region and the suspect terrains (Coney, Jones & Monger 1980) along the west coast of North America. The margins of continents can also be modified through time in many other ways (Burk & Drake 1974), and some of the problems of fit may be resolved if the contemporary margin