Vol. 320, Issue 5, 2020

Science Paper
Avalonian Arc-To-Platform Transition in Southeastern New England: U-Pb Geochronology and Stratigraphy of Ediacaran Cambridge “Argillite,” Boston Basin, Massachusetts, USA
Margaret D. ThompsonJames L. Crowley
High-precision CA-TIMS 206Pb/238U zircon dates clarify the age and tectonic significance of the Cambridge Formation which is poorly exposed in the Boston Basin, eastern Massachusetts, but transected by ∼50 km...
Science Paper
Tectonics and Foreland Basin Development at the Leading Edge of the Humber Arm Allochthon, Western Newfoundland, Canadian Appalachians
Ryan A. LacombeJohn W. F. WaldronS. Henry Williams
The thrust front of the Northern Appalachians involves Ediacaran rift-related structures of the Laurentian margin that were re-worked in Taconic (Ordovician), Salinic (mainly Silurian) and Acadian (mainly Devonian) deformation events....