Provenance and Paleozoic tectonic evolution of Ganderia and its relationships with Avalonia and Megumia in the Appalachian-Caledonide orogen

•Ganderia’s provenance in Amazonia.•Cambrian rifting and scissor-like opening of Rheic Ocean in Penobscot backarc region.•Complex Cambrian to Tremadocian interaction with East Avalonia along the margin of West Gondwana.•Diachronous accretion to Laurentia over time span of ca. 50 my.•Tectonic elements show marked non-cylindricity.