Background and outline

Abstract

The compilation of a more complete history of the Earth calls for recognition of ancient seas that were swept by strong tidal currents. Few examples of these seas are known, though ancient tidal flat deposits are distributed widely in the stratigraphic record and are found in many parts of the world. Modern offshore tidal current deposits can cover larger areas of sea floor than the adjacent modern tidal flats and a similar ratio must be expected for ancient seas. The deposits of some ancient seas may hold a record of periods of relatively higher tidal energy than at present, which could indicate such events as the possible capture of our Moon (Olson, 1970) and of any near-misses of the Earth by other bodies.