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<jats:title>Abstract</jats:title><jats:p>The Mongolian micro‐continental fragments play an important geodynamic role in the Palaeozoic evolution of the Central Asian Orogenic Belt. However, the original provenance of individual blocks within the Nuna/Columbia and Rodinia supercontinents is not well constrained. In this work, we present zircon U–Pb and Lu–Hf isotopic data from the Mesoproterozoic to Neoproterozoic metamorphosed cover of the Baidrag Block in central Mongolia. These data reveal important maxima in the Neoarchean, Palaeoproterozoic and locally Neoproterozoic. Although the majority of the new data can be attributed to local sources within the basement of the Mongolian micro‐continental fragments, an important contribution of juvenile 2.0 Ga zircons is linked to the western margin of the Siberian Craton, and 1.5 Ga zircons are either directly derived from North Australia or indirectly recycled from sediments in NW Laurentia.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The north‐western Alpine foreland in Switzerland and France comprises the Late Miocene Jura Mountains, considered a type example for thin‐skinned thrusting where deformation of the sedimentary cover is decoupled from the basement along a regional basal detachment. To what extent basement faults were involved during its deformation is a matter of debate. We use 3D seismic data to investigate the deformation style along the easternmost tip of the Jura range in unprecedented detail. Here, basement‐rooted normal faults were not only repeatedly reactivated before thrust belt formation but also contemporaneously active as reverse/transpressional faults. They either propagated up into the Mesozoic succession without interruption (‘hard linkage’) or apparently controlled the localisation of Mesozoic faults via smaller‐scale shear zones (‘soft linkage’). Our analysis of the resulting fault geometries questions the existence of a large‐scale basal detachment in this area and points out the importance of thick‐skinned fault reactivation.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The late Miocene Monte Capanne and Porto Azzurro plutons are investigated by means of coupled U–Pb zircon and <jats:sup>40</jats:sup>Ar/<jats:sup>39</jats:sup>Ar white mica dating to test the occurrence of long‐lived magmatic systems in the upper crust. Zircon crystallized for &gt;1 Ma in both plutonic systems, with supersolidus conditions overlapping for ~220 ka indicating previously unrecognized co‐existence of the two reservoirs. The development of the Porto Azzurro high T‐aureole is post‐dated by continuous igneous zircon crystallization until ~6.0 Ma. By linking crystallization to post‐emplacement cooling of late‐stage pulses in both western and eastern Elba we constrain long‐lived sizeable reservoirs (possibly the same reservoir) in the Tyrrhenian upper crust between ~8 and 6 Ma.</jats:p>

<jats:title>Abstract</jats:title><jats:p>The formation of rodingites has been a continually controversial topic, largely due to the absence of minerals that can be unambiguously dated. Here, we present a case study that utilized LA‐ICPMS garnet U–Pb dating, in conjunction with field investigations, petrology and Raman spectroscopy, to reveal the age and petrogenesis of rodingite in the northern North China Craton. The rodingites are spatially associated with mafic and alkaline rocks. Our findings indicate that rodingitization occurred at ca. 388 Ma, making it about 5–10 Myr younger than its mafic protoliths, but contemporaneous with the adjoining alkaline plutons. These observations suggest that the rodingitization may be attributed to hydrothermal fluids from the alkaline magmas. Our study emphasizes the importance of utilizing garnet U–Pb dating to determine the timing of rodingitization and introduces a novel perspective on the relationship between rodingitization and alkaline magmas in extensional continental settings.</jats:p>

<jats:title>Abstract</jats:title><jats:p>We document the complex interaction between metamorphic reactions and deformation behaviour at high‐pressure conditions by combining (micro‐) structural, petrographical and geochemical data from an eclogite body. The well‐equilibrated eclogite fabric is crosscut by mineral veins. Precipitated veins host the eclogitic high‐pressure assemblage with variation in modal composition, indicating that fracturing occurred at eclogite facies conditions. Deflection of the eclogite fabric adjacent to the veins implies ductile reactivation of the veins as flanking structures and strain localization under continuous aseismic shearing. In consequence, the reactivated veins are characterized by undulatory extinction and subgrain formation in quartz indicating crystal plasticity. We show that prograde post‐eclogitization metamorphism resulted in progressive dehydration and melting of the eclogite. Subsequent increase in pore‐pressure‐induced rock failure. The mesoscopic to microscopic characteristics of eclogite‐facies veins indicate a cyclic behaviour of fracturing, vein formation and crystal‐plasticity which demonstrates the strong interaction of chemical and mechanical processes operating at depth.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Throughout the Phanerozoic and more, the Earth has experienced cold and hot periods, which are typically associated with long‐lasting (hundreds of million years, Ma) greenhouse and icehouse climate regimes. Now, most published sea‐level curves report two main maxima in the Cretaceous and Ordovician superimposed on a multitude of short‐term fluctuations. The big humps are shown to be predominantly the results of the plate tectonic configuration, not icehouse and greenhouse regimes, suggesting that the small oscillations are related to continental ice variations. From this point of view, it can be inferred that polar ice caps are present almost all the time, and climate regime changes appear much more frequent and shorter than usually considered and are not well‐documented from glaciogenic deposits. Relying on short‐term oscillations, the volume of continental ice can be retrieved over the Phanerozoic.</jats:p>

<jats:title>Abstract</jats:title><jats:p>Canada's northern cratons record a complex poly‐metamorphic evolution in response to multiple orogenic events. The Snowbird Tectonic Zone (STZ), the principal suture between the Archean Rae and Hearne cratons, is a highly debated structure; it is argued to have accommodated modern‐style accretion in either the Neoarchean (2.6–2.5 Ga) or Palaeoproterozoic (ca. 1.9 Ga). To resolve this controversy, we use Lu–Hf garnet geochronology to date an eclogite collected from the East Athabasca mylonite triangle of the STZ. Garnet shows prograde trace‐element zoning, and we obtained an age of 1914.5 ± 3.4 Ma. The age is interpreted to date the timing of collision related to deep burial of crust along the STZ. This strongly supports Palaeoproterozoic terminal collision between the Rae and Hearne cratons, and that to constrain high‐pressure metamorphism during supercontinent assembly, dating eclogite itself is key.</jats:p>