Geochronology of detrital zircons from the Elzevir and Frontenac terranes, Central Metasedimentary Belt, Grenville Province, Ontario: Discussion

Abstract

The paper by E.A. Sager-Kinsman and R.R. Parrish represents a valuable contribution to the ongoing effort to unravel the tectonic magmatic history of the Central Metasedimentary Belt in the Grenville Province. However, we feel that some of the implications of this study have been understated by the authors, particularly with respect to the understanding of the evolution of the margin of the North American craton during the Middle Proterozoic. Our discussion focuses on three specific areas of the authors' study, namely, (1) implications of their study to the published tectono-stratigraphy of the Frontenac Terrane; (2) implications with respect to the age of the Frontenac Terrane relative to the remainder of the Central Metasedimentary Belt in Ontario; and (3) implications with respect to the distribution of 1.8 Ga orogenic belts in North America and reconstruction of Laurentia during the Middle Proterozoic.