01556nas a2200181   4500008004100000022001400041245016800055210006900223300001200292490000800304520084700312100001601159700002401175700001401199700002501213700002201238856011401260       2019                        eng d  a0016-760600aEarly Paleozoic rifting and reactivation of a passive-margin rift: Insights from detrital zircon provenance signatures of the Potsdam Group, Ottawa graben: Comment0 aEarly Paleozoic rifting and reactivation of a passivemargin rift  a695-6980 v1313 a<p>This comment outlines fundamental problems in Lowe et al.’s synthesis (2018) of the early Paleozoic stratigraphic architecture of the eastern Ottawa-Bonnechere aulacogen that preclude an accurate analysis of the region’s geological and depositional history and even an adequate stratigraphic provenance of the detrital zircons that they analyze. These problems include: inaccurate lithostratigraphic and contradictory biostratigraphic correlations that have also led to extension of the Potsdam “Group” into the Lower Ordovician; a proposed allostratigraphy that contradicts itself when tested with existing litho- and biostratigraphic data; redefinitions of earlier defined lithostratigraphic units that lead to confusion on close reading; and errors in interpreted depositional environments and lithostratigraphic contacts.</p>
1 aLanding, E.1 aHersi, Osman, Salad1 aAmati, L.1 aWestrop, Stephen, R.1 aFranzi, David, A.  uhttps://pubs.geoscienceworld.org/gsa/gsabulletin/article/568494/Early-Paleozoic-rifting-and-reactivation-of-a