Mesozoic apparent polar-wander path for South America

Abstract

An improved Mesozoic apparent polar-wander path incorporates recent data from South America. Criteria of selection applied to the paleomagnetic poles in calculating the mean poles arc 1) synchroneity of units, 2) stability of remanent magnetization, and 3) tectonic stability of sample areas. Mean composite poles are given  for the Late Triassic and Jurassic times. These incorporate African mean poles rotated by fitting Africa against South America. Separate poles are given for Early Cretaceous and Late Cretaceous epochs. Mean composite Cretaceous poles arc not calculated because of the probability of separation of Africa from South America in the Cretaceous. The apparent polar-wander path for South America oscillates across a position close to the South geographic pole. Abrupt turns appear in the paleopole path near the Paleozoic Mesozoic boundary, and again in Late Cretaceous time.