The Relative Ages or the Otto Stock and Matachewan Dyke Magnetizations

Abstract

<p> A baked contact test was carried out between the Otto Stock, dated at 2114 Ma by Bell and Blenkinsop (1976) and its host rock, represented by the magnetically stable, Matachewan Dyke swarm dated at 2690 Ma by Gates and Hurley (1973). Paleomagnetic results from this study confirm the recently revised dating or the Otto Stock and Matachewan dykes at 2680±1 Ma and 2452+3/-2 Ma, resectively (Corru et.al. 1989; Heaman, 1988) . </p> <p> Matachewan dykes both distant and within the contact aureole or the Otto Stock all carry the same southwesterly shallow characteristic Matachewan direction or magnetization. The absense or an Otto Stock overprint on the Matachewan dykes implies that the intrusion or the Otto Stock must have occurred before the intrusion or the Matachewan Dyke swarm. </p> <p> The relative ages or the Otto Stock and Matachewan dyke magnetizations are inconsistent with the conventional early Proterzoic apparent polar wander path (APWP) for North America, which decreases in age from the Matachewan dyke pole t o the Otto Stock pole. It can be concluded that this part or the APWP is running backwards and must now be redefined. </p>