Du Toit's reconstruction of the Gondwanaland supercontinent during late Paleozoic time based upon congruence of shorelines, matching of structural features in ancient basement rocks (lines), and late Paleozoic orogenic belts-here combined in what Du Toit called Samfrau geosyncline (from the combination of letters from the names of three continents). Apparently a microcontinent compressed the Samfrau belt against main Gondwanaland in Permo-Triassic time. After reconstructing, Du Toit plotted distributions of Gondwana rocks and especially glacial phenomena. Heaviest lines at left represent same boundary on both continents between two major isotopic date provinces. (Adapted from Du Toit, 1937.)
Source: Dott and Prothero, 1994.
