SWEAT (which stands for Southwestern United States and East Antarctica) is the hypothesis that the Southwestern United States was at one time connected to East Antarctica.
The hypothesis of a late Precambrian fit of western North America with the Australia-Antarctic shield region permits the extension of many features through Antarctica and into other parts of Gondwana. For example, the Grenville orogen may extend around the coast of East Antarctica into India and Australia, and the ophiolitic belt of the latter may extend into East Antarctica. The Wopmay orogen of northwest Canada may extend through eastern Australia into Antarctica and thence beneath the ice to connect with the Yavapai-Mazatzal orogens of the southwestern United States. Counterparts of the Precambrian-Paleozoic sedimentary rocks along the U.S. Cordilleran miogeocline may be present in the Transantarctic Mountains. Orogen boundaries provide useful piercing points for Precambrian continental reconstructions.
The model implies that Gondwana and Laurentia drifted away from each other on one margin and collided some 300 million years later on their opposite margins to form the Appalachians.