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We report new, highly precise, U -Pb and Ar/Ar ages for seven Cretaceous rhyolites, tuffs and granites from across Zealandia spanning a 30 Ma period from arc magmatism to continental break-up. Combined with previously published data, these reveal a strong episodicity in Cretaceous silicic magmatism outside the Median Batholith. 112 Ma tuffs are known only from the Eastern Province in association with a Cretaceous normal fault system. Both 101 and 97 Ma groups of rhyolites and tuffs occur across the entire width and half the length of Zealandia from near the palaeotrench to the continental interior, indicating widespread and effectively instantaneous extension. We attribute an increase in A-type character with time (112-101-97-88-82 Ma) to the progressive thinning of the Zealandia continental crust whereby, with time, there is less opportunity for crustal contamination. Extension directions associated with 101, 97 and 82 Ma magmatism and associated core complex exhumation across Zealandia are all oriented c. 308 oblique to the margin. These observations suggest Zealandia rifting was controlled by either .83 Ma capture of Zealandia by the Pacific Plate and/or ,83 Ma Zealandia-West Antarctica spreading, rather than by laterally migrating triple junctions, slab windows or plume heads.

Regional ductile thrusting and syn-kinematic granitic magmatism within the Caledonides of northern Scotland occurred within a sinistrally oblique convergent tectonic setting during the Silurian closure of the Iapetus Ocean. The highest thrust nappes are dominated by structures of probable Grampian (Ordovician) age, and Scandian (Silurian) deformation dominates the underlying thrust nappes. Deformation was overall foreland-propagating but the nappe stack was modified by out-of-sequence thrusting and probable synchronous development of thrusts at different structural levels. Localized dextrally transpressive deformation is related to an inferred lateral ramp located offshore. New U–Pb zircon ages from syn-tectonic granites indicate that the internal Naver Thrust was active between c. 432 and c. 426 Ma. This is consistent with other data sets that indicate that contractional deformation and high-grade metamorphism, and by implication displacements in the Moine Thrust Zone, may have lasted until c. 420–415 Ma. The synchroneity of thrusting and strike-slip movements along the Great Glen Fault implies that partitioning of transpressional strain occurred above a regional basal decollement. The short duration of the Scandian orogen in Scotland (c. 437–415 Ma?) is consistent with only moderate crustal thickening and a location on the periphery of the main Laurentia–Baltica collision further north.Supplementary material: Details of analytical procedures, complete U-Pb isotopic data and methods of U-Pb age calculation and error reporting are available at https://doi.org/10.6084/m9.figshare.c.4962251

Unconformity below Cambrian-Ordovician, western Tindouf Basin; 2-Unconformity below Ordovician, eastern Tindouf Basin; 3-Astroblem; 4-Approximate boundary between Zednes and Tiris Archean domains; 5-Unconformity below Mesoproterozoic Groupe de Char; 6-Taziast klippe; 7-Mafic sills of Central Atlantic Magmatic Province, CAMP; 8-Assabet forelandbasin deposits; 9-Unconformity below Groupe de Jbéliat glacial deposits; 10-Frontal thrust in Northern Mauritanides; 11-Tacarat-Inemmaudene Shear Zone; 12-Guelb er Richat, subsurface laccolith; 13-Stratigraphic section in Figure 8; 14-Akjoujt sector of Mauritanide thrust belt; 15-Archean tectonic windows beneath Mauritanide thrust belt; 16-Oujeft foreland-basin deposits; 17-Frontal thrust in Central Mauritanides; 18-Early Neoproterozoic basement in Central Mauritanides; 19-Parautochthon in Central Mauritanides; 20-Allochthon in in Central Mauritanides; 21-Unconformity below Mesozoic-Cenozoic coastal basin deposits; 22-Kandou Formation, Hercynian foreland basin;

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