Prior to their Alpine overprinting, most of the pre-Mesozoic basement areas in Alpine orogenic structures shared a complex evolution, starting with Neoproterozoic sediments that are thought to have received detrital input from both West and East Gondwanan cratonic sources. A subsequent Neoproterozoic-Cambrian active margin setting at the Gondwana margin was followed by a Cambrian-Ordovician rifting period, including an Ordovician cordillera-like active margin setting. During the Late Ordovician and Silurian periods, the future Alpine domains recorded crustal extension along the Gondwana margin, announcing the future opening of the Paleotethys oceanic domain. Most areas then underwent Variscan orogenic events, including continental subduction and collisions with Avalonian-type basement areas along Laurussia and the juxtaposition and the duplication of terrane assemblages during strike slip, accompanied by contemporaneous crustal shortening and the subduction of Paleotethys under Laurussia. Thereafter, the fi nal Pangea assemblage underwent Triassic and Jurassic extension, followed by Tertiary shortening, and leading to the buildup of the Alpine mountain chain. Recent plate-tectonic reconstructions place the Alpine domains in their supposed initial Cambrian-Ordovician positions in the eastern part of the Gondwana margin, where a stronger interference with the Chinese blocks is proposed, at least from the Ordo vician onward. For the Visean time of the Variscan continental collision, the distinction of the former tectonic lower-plate situation is traceable but becomes blurred through the subsequent oblique subduction of Paleo tethys under Laurussia accompanied by large-scale strike slip. Since the Pennsylvanian, this global collisional scenario has been replaced by subsequent and ongoing shortening and strike slip under rising geothermal conditions, and all of this occurred before all these puzzle elements underwent the complex Alpine reorganization.

The Austroalpine basement underwent a multistage Precambrian to Tertiary evolution. Meta-magmatic rocks occur in pre-Early Ordovician and post-Early Ordovician units. Protolith zircon ages and whole-rock trace element data define two magmatic evolution lines. An older trend with Th/Yb typical of subduction-related metamorphism, started by 590 Ma N-MORB-type and 550–530 Ma volcanic arc basalt-type basic suites which mainly involved depleted mantle sources, and was continued by mainly crustal-source 470–450 Ma acid magmatic suites. A presumably younger evolution by tholeiitic MORB-type and 430 Ma alkaline within-plate basalt-type suites is characterized by an intraplate mantle metasomatism and multicomponent sources. These magmatic trends can be related to a Neoproterozoic to Ordovician active margin and a subsequent Palaeo-Tethys passive margin along the north-Gondwanan periphery. During Variscan collision, the Austroalpine basement underwent multiphase deformation and metamorphism. Early deformation involved non-coaxial shearing with formation of sheath folds and calcsilicategneiss bodies in some regions. Syndeformational clockwise P–T paths in lower basement parts passed high-pressure and high-temperature amphibolite-facies stages and are interpreted by a Devonian to Carboniferous crustal stacking. A post-collisional Permian thermal event is documented by pegmatite intrusions, LP-HT assemblages and monazite ages. Ductile overprinting under greenschist-facies conditions during the Cretaceous is indicated by foliated pegmatites and monazite ages in samples with retrogressed garnet. The emplacement of the Oligocene Rieserferner pluton was controlled by sinistral shear zone deformation along the Defereggen–Antholz–Vals line. Shear zone activity ceased at 15 Ma and was superseded by brittle strike-slip movements along NW and SE trending faults.

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Polymetamorphic garnet micaschists from the Austroalpine Saualpe Eclogite Unit (Kärnten, Austria, Eastern Alps) display complex microstructural and mineral–chemical relationships. Automated scanning electron microscopy routines with energy dispersive X‐ray (EDX) spectral mapping were applied for monazite detection and garnet mineral–chemical characterization. When the Fe, Mg, Mn and Ca element wt% compositions are used as generic labels for garnet EDX spectra, complex zonations and porphyroblast generations can be resolved in complete thin sections for selective electron‐microprobe analyses. Two garnet porphyroblast generations and diverse monazite age populations have been revealed in low‐Ca and high‐Al‐metapelites. Garnet 1 has decreasing Mn, constant Ca and significantly increasing Mg from cores to rims. Geothermobarometry of garnet 1 assemblages signals a crystallization along a M1 prograde metamorphism at ~650 °C/6–8 kbar. Sporadic monazite 1 crystallization started at c. 320 Ma. Subsequent pervasive 300–250 Ma high‐Y and high‐Gd monazite 1 formation during decompression coincided with the intrusion of Permian and Early Triassic pegmatites. Monazite 1 crystallized along the margin of garnet 1. Coronas of apatite and allanite around the large 320–250 Ma monazite signal a retrogressive stage. These microstructures suggest a Carboniferous‐to‐Early‐Permian age for the prograde M1 event with garnet 1. Such a M1 event at an intermediate‐P/T gradient has not yet been described from the Saualpe, and preceded a Permo‐Triassic low‐P stage. The M2 event with garnet 2 postdates the corona formation around Permian monazite. Garnet 2 displays first increasing XCa at decreasing XMg, then increasing XCa and XMg, and finally decreasing XCa with increasing XMg, always at high Ca and Mg, and low Mn. This records a P–T evolution which passed through eclogite facies conditions and reached maximum temperatures at ~750 °C/14 kbar during decompression‐heating. A monazite 2 population (94–86 Ma) with lower Y and Gd contents crystallized at decreasing pressure during the Cretaceous (Eo‐Alpine) metamorphism M2 at a high‐P/T gradient. The Saualpe Eclogite Unit underwent two distinct clockwise metamorphic cycles at different P–T conditions, related to continental collisions under different thermal regimes. This led to a characteristic distribution pattern of monazite ages in this unit which is different from other Austroalpine basement areas.

In the Austroalpine Basement to the south of the Tauern Window, distinct suites of metabasites occur with orthogneisses in pre-Early-Ordovician units. Tholeiitic and alkaline within-plate basalt-type metabasites are associated with acid meta-porphyroids in the post-Early-Ordovician Thurntaler Phyllite Group. According to their correlated trace element abundances, metabasite zircons crystallized with their host rocks. Protolith Pb-Pb zircon ages, wholerock Ta/Yb-Th/Yb and oxygen, Sr, Nd isotope data define two principal evolution lines. An older evolution at elevated Th/Yb typical of subduction-related magmatism, started by 590-Ma N-MORB-type and 550-530 Ma volcanic arc basalt type basic suites, which mainly involved depleted mantle sources. It finished with mainly crustalsource 470-450-Ma acid magmatites. An other evolution line by tholeiitic and 430-Ma alkaline within-plate basalttype suites in both pre-and post-Early-Ordovician units is characterized by an intraplate mantle metasomatism and enrichment trend along multicomponent sources. These magmatic evolution lines can be related to a plate tectonic scenario that involved terranes in a progressively mature Neoproterozoic to Ordovician active margin, and a subsequent Palaeo-Tethys passive margin along the north Gondwanan periphery.

Combined field structural analysis with in situ electron probe microanalysis Th‐U‐Pb monazite dating, petrologic, and microstructural data provides a reconstruction of the pressure‐temperature‐deformation‐time (P‐T‐D‐t) path of the Gondwanide basement of the North Patagonian Cordillera. For samples from the Challhuaco hill, the timing of development of the metamorphic S2 foliation and associated L2 lineation and tight to isoclinal F2 folds is constrained by monazite ages of 299 ± 8 and 302 ± 16 Ma during peak metamorphic conditions of ~ 650 °C and 11 kbar, achieved during prograde metamorphism and progressive deformation. Metamorphism and deformation of metamorphic complexes of the North Patagonian Andes seem to record Late Paleozoic crustal thickening and are coeval with metamorphism of accretionary complexes exposed further west in Chile, suggesting a coupled Late Devonian‐Carboniferous evolution. Instead of the result of continental collision, the Gondwanide orogeny might thus be essentially linked to transpression due to advancing subduction along the proto‐Pacific margin of Gondwana. On the other hand, second generation of monazite ages of 171 ± 9 and 170 ± 7 Ma constrains the timing of low‐grade metamorphism related to kink band and F3 open fold development during Jurassic transtension and emplacement of granitoids. Finally, a Cretaceous overprint, likely resulting from hydrothermal processes, is recorded by monazite ages of 110 ± 10 and 80 ± 20 Ma, which might be coeval with deformation along low‐grade shear zones during the onset of Andean transpression.

Metabasites in the Dalradian Argyll and Southern Highland Groups experienced multiphase deformation and coeval Barrovian-type prograde and retrograde metamorphism during the Caledonian Grampian orogeny. Metamorphic Ca-amphiboles crystallized with plagioclase,epidote,chlorite and quartz, and sometimes with garnet and clinopyroxene. The minor changes in metabasite mineral assemblages and systematic mineral-chemical variations in Ca-amphibole confirm the classical concept of increasing metamorphic grade in metapelitic Chlorite to Sillimanite zones. In the Chlorite zone, high-Ti brown amphibole enclosed by green Ca-amphibole is interpreted as a magmatic relic. In the Chlorite, Biotite,Garnet and Andalusite zones, Ca-amphibole displays zonation with actinolite in cores and magnesio-hornblende to tschermakite in rims. Poor amphibole zonations occur in the Kyanite and Sillimanite zones. Ca-amphibole zonations are best described in terms of IVAl, VIAl and Ti which semiquantitatively monitor temperature and pressure changes. Maximal IVAl in amphibole increase with metamorphic grade. Empirically calibrated amphibole equilibria enabled us to reconstruct coherent prograde P-T paths and maximal P and T from the mineral zones; with Tmax of 680±50°C in the Sillimanite zone and Pmax of 8±1.2 kbar in the Kyanite zone. Prograde P-T paths indicate that elevated geothermal gradients should be considered even at the beginning of the Grampian Barrovian metamorphism.

The Isla Cristalina de Rivera crystalline complex in northeastern Uruguay underwent a multistage magmatic and metamorphic evolution. Based on SHRIMP U-Pb zircon, Th-U-Pb monazite (CHIME-EPMA method) and K-Ar age data from key units several events can be recognized: (1) multistage magmatism at 2,171-2,114 Ma, recorded on zircon of the granulitic orthogneisses and their 2,093-2,077 Ma overgrowths; (2) a distinct amphibolite facies metamorphism at *1,980 Ma, recorded by monazite; (3) greenschist facies reworking and shearing at ca. 606 Ma (monazite and K-Ar on muscovite) along the Rivera Shear Zone, and finally (4) intrusion of the post-tectonic Sobresaliente and Las Flores granites at around 585 Ma. Lithological similarities, geographic proximity and coeval magmatic and metamorphic events indicate a similar tectonometamorphic evolution for the Isla Cristalina de Rivera, the Valentines Block in Uruguay and the Santa María Chico Granulitic Complex in southern Brazil, since at least 2.1 Ga.