ACKNOWLEDGMENTS

We express our appreciation to B.E.B. Cameron for collecting the samples and to M. Johns for their preparation. J. Page contributed significant effort in stratigraphically organizing the data utilized in this study. We would like to thank Lindsay Upiter, Carleton University for reformatting the systematic figures. We would also like to thank the anonymous reviewers for their very detailed and valuable suggestions and contributions. Financial support was provided by an NSERC Discovery Grant to R.T. Patterson and by Geological Survey of Canada Project #870070 under J.W. Haggart. Geological Survey of Canada Contribution 20070308.