The Plate Tectonic History of the Past Tethys Ocean

Originally, Tethys was defined as an equatorial ocean ancestral to the Alpine—Himalayan mountain ranges (Suess, 1893). The concept followed an earlier definition, under the name “Zentrales Mittlemeer,” of a Jurassic seaway that extended from the Caribbean to the Himalayas (Neumayr, 1885) and, thus, included the Jurassic Atlantic Ocean together with the Alpine—Himalayan Belt. Plate tectonic concepts, in contrast with geosynclinal concepts that mingled a past ocean with an orogenic belt, permitted the recognition of parts of the same Jurassic ocean, located in the Atlantic and the Alps, as being either submitted, or not, to later orogeny (Bernoulli, 1972). Since then (Aubouin et al., 1980; Bernoulli and Lemoine, 1980), the name “Tethys” has been applied to the whole oceanic realm, including the Mesozoic Central Atlantic, which separated North America, Europe, and Asia to the north, from South America, Africa, India, Australia, and Antarctica to the south (Fig. 1). Remnants of Tethys now are found within Alpine mountain belts from the Caribbean in the west to the recent collision zone between Australia and Eurasia in the East, and within the still-growing Central Atlantic Ocean between Africa and North America.