PLATE 3 

 Ordovician Tectonic Map 



Westward thrusting occurred at the close of the Ordovician in eastern New 

 York against the Adirondack dome. Some ultrabasic intrusions may have been 

 emplaced in the Maritime Provinces and Newfoundland at the close of the 

 Ordovician. W. A. Waverly arch of Early Ordovician time. 





