Middle Paleozoic archipelago amalgamation and tectonic transform in the northern West Junggar, NW China: Constraints from magmatism and deformation

•Post-collisional felsic intrusions were emplaced between 433 and 423 Ma.•Two-phase deformation events occurred in the Saier Mountains.•Late Devonian slab roll-back caused the emplacement of mafic dike swarms.•Archipelago amalgamation occurred in the northern WJ during the middle Paleozoic.