South American palaeozoic palaeomagnetic results and the welding of Pangaea

Abstract

Cambrian, Ordovician and Lower Devonian sediments from northern Argentina have been examined palaeomagnetically. Of the six Cambrian localities investigated, five are shown to have magnetically stable deposits. The Devonian samples, however, are demonstrated to hold two secondary magnetizations and no detectable primary remanence. The five Cambrian and one Ordovician palaeomagnetic pole positions South Tilcara 52N 27E (A 95 =23 Purmamarca vill 61N 67E (A 95 =26 North Tilcara 49N 24E (A 95 =23 Purmamarca 5N 39E (A 95 =14 Abra de Cajas 2N 28E (A 95 =50 Salta (Ordovician) 31N 13E (A 95 =40) are used in conjunction with three previously determined Lower Palaeozoic palaeomagnetic pole positions to suggest a new South American Lower Palaeozoic polar wander path, which with palaeomagnetic results from other southern continents forms a common Gondwanan Lower Palaeozoic polar wander path. The relationship of the Gondwanan curve with the North American, European and Asian Palaeozoic polar wander paths is discussed in terms of the welding of Pangaea.