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<jats:p> This study presents Lu–Hf data on detrital zircon grains from the Lower Paleozoic metasedimentary successions of the Sierra Albarrana Domain (SW Iberian Massif). We provide new information about their origin, record of continental crustal evolution and geological affinity. Previous detrital zircon U–Pb data in this terrane reveal two main age populations, with age peaks at <jats:italic>c.</jats:italic> 595 Ma and <jats:italic>c.</jats:italic> 1.90 Ga. The Ediacaran events are interpreted to represent a magmatic arc with input of juvenile magmas intruding into the Eburnean basement of Gondwana, and probably mixing with it. The different evolutionary stages of the arc were probably linked to the Cadomian Orogeny during Neoproterozoic–earliest Cambrian times. The Paleoproterozoic zircon population corresponds to the Eburnean Orogeny. The magmas derived from an Eburnean depleted mantle partly intruded an older basement, leading to an incipient mixing process. <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> Hf isotopic compositions indicate a possible affinity with the Central Iberian Zone, suggesting a common geological setting during Ediacaran–Cambrian times but different settings during the Paleoproterozoic. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> A dataset of Lu/Hf analyses and a regional comparison of the <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> Hf( <jats:italic>t</jats:italic> ) dataset with published data for metasedimentary rocks of the Iberian Massif are available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6420215">https://doi.org/10.6084/m9.figshare.c.6420215</jats:ext-link> </jats:p>

<jats:p> The tectonic and crustal evolution of the East Kunlun Orogen in the Triassic remains unclear. We investigated the Triassic andesites (235 and 216 Ma) to investigate these issues. The Mid- and Late Triassic andesites are calc-alkaline with enriched Sr–Nd isotopic compositions: ( <jats:sup>87</jats:sup> Sr/ <jats:sup>86</jats:sup> Sr) <jats:sub>i</jats:sub>  = 0.709210–0.709758 and <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>Nd</jats:sub> ( <jats:italic>t</jats:italic> ) = −8.0 to −6.9. The Mid-Triassic andesites have higher Mg, Cr and Ni contents and more depleted Hf isotopic compositions ( <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>Hf</jats:sub> ( <jats:italic>t</jats:italic> ) = −4.2 to 1.3) than the Late Triassic andesites ( <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>Hf</jats:sub> ( <jats:italic>t</jats:italic> ) = −7.4 to −5.8). These features are explained by the derivation of magma from partial melting of the mafic lower continental crust, although minor lithospheric mantle materials are also involved in the Mid-Triassic andesites. The andesites were generated in extensional settings related to slab break-off in the Mid-Triassic and lithospheric delamination in the Late Triassic, respectively. The Late Triassic magmatic suites are higher in K and represent a more mature continental crust, indicating that crustal reworking in extensional settings contributes to crustal maturation. In combination with the regional magmatic, structural and sedimentary records, we propose that the East Kunlun Orogen evolved from oceanic subduction in the Late Permian to Mid-Triassic through continental collision in the Mid-Triassic to post-collision in the Late Triassic. </jats:p>

<jats:p>The Cretaceous marine sedimentary record is characterized by time intervals rich in organic matter correlating with positive carbon isotope excursions, often called oceanic anoxic events. The Weissert Event corresponds to the first such event in the Cretaceous during the Valanginian stage. The associated palaeoenvironmental perturbations, which include increasing marine surface water primary productivity, are hypothesized to have been triggered by volcanic activity from large igneous provinces, and the source of nutrients is not well constrained (continental runoff v. oceanic upwelling). We present isotope ratios of Pb, Sr and Nd, together with concentrations of major and trace elements, for sediments from the central Moroccan margin to test these hypotheses. We demonstrate that the nutrient input was dominated by continental weathering. The source of sedimentary material remained stable during the Valanginian interval and originated from an old source, probably the African Sahara region. The radiogenic isotope signatures do not show a significant contribution of volcanic products from any known Valanginian large igneous province to the geochemical budget of sediments deposited on the central Moroccan margin. Although this does not preclude an impact of volcanic activity on the composition of seawater, it demonstrates that the erupted volumes were not sufficient to affect the deposited sediments.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> The Supplementary Table contains three sheets: (1) Central Moroccan Margin, the analytical data generated and analysed during this study; (2) Fig. 8 data, large igneous provinces, the data of known Valanginian large igneous provinces used for comparison; and (3) Fig. 9 and S5 data, source areas, the data of potential surrounding source areas used for comparison, available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://doi.org/10.6084/m9.figshare.c.6333040">https://doi.org/10.6084/m9.figshare.c.6333040</jats:ext-link> . </jats:p>

<jats:p>Las Hoyas (Cuenca, Spain) represents a unique Early Cretaceous (Barremian) fossil biota of a wetland. The site has yielded a particularly diverse assemblage of &gt;20 000 plant and animal fossils, many of which present unprecedented soft tissue preservation, including microstructural details. Among the most significant discoveries are the oldest angiosperms, the smallest species of chondrichtians and squamates, new theropod dinosaurs, including several enantiornithine birds, the first European tapejarid pterosaur and the most complete eutriconodont mammal. Such discoveries have produced data on important aspects related to plant and animal evolution, such as the first steps in flower development by plants, insights into unknown anatomical and diet specializations in theropod dinosaurs, the development of flight manoeuvrability in early birds, the unexpected global distribution of tapejarid dinosaurs and ground-breaking data on early mammalian hair development. There are many more discoveries to unveil and new research is now linking the immense wealth of palaeobiological information with mathematical procedures to study the ecological structure of the wetland.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Taxonomic structure of the Las Hoyas diversity and systematic list of unearthed taxa are available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6336914">https://doi.org/10.6084/m9.figshare.c.6336914</jats:ext-link> </jats:p>

<jats:p>The Central Asian Orogenic Belt (CAOB) represents a Late Paleozoic archipelago. Yet the crustal growth, reworking and exhumation of individual microcontinental massifs remain poorly constrained. Here, we utilize the Axi epithermal deposit to examine continental preservation and exhumation of CAOB in the Chinese Western Tianshan. Zircon U-Pb dating and geochemistry demonstrate that the andesitic host rock formed by incremental addition of magma in an Andean-type magmatic arc setting at 362, 354 and 342 Ma. Pyrite Re-Os data and textural evidence reveal two mineralization events at 355 and 332 Ma. Zircon (U-Th)/He data reveal temperatures of ∼180 °C until 317.8 ± 9.8 Ma, which is interpreted to record the timing of exhumation of the andesite and gold orebodies prior to their burial by Carboniferous aged sediments. Further sedimentary concealment continued until the Late Mesozoic, when the system was re-exhumed between 148.6 ± 8.6 and 120.0 ± 13 Ma at a rate of ∼9.8 m/Ma as shown by apatite (U-Th)/He data . Collectively, the geo-/thermochronology demonstrates that the Chinese Western Tianshan records the transition from compressional to extensional tectonism during the Late Paleozoic and the Late Mesozoic. The shallow epithermal mineralization was protected from erosion by post-mineralization deposition.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6640014">https://doi.org/10.6084/m9.figshare.c.6640014</jats:ext-link> </jats:p>

<jats:p>Fuerteventura and Lanzarote (Eastern Canary Islands), form the oldest emerged part of the archipelago. Geologically, they can be considered a single edifice, constituting a continuous volcanic ridge extending 250 km from SW to NE. This work completes the dating and the determination of the magnetic stratigraphy of the shields and the rejuvenated volcanism of Fuerteventura and Lanzarote, refining the volcanic stratigraphy and cartography. The new unspiked K-Ar ages and magnetostratigraphy of Fuerteventura and Lanzarote indicate that these islands developed patterns similar to those of the Central and Western Canary Islands, building adjacent and successively superimposed basaltic shield volcanoes during the Miocene, between 20.19 ± 0.30 and 6.30 ± 0.11 Ma. The overlay of post-Miocene rejuvenated volcanism hinders the extent and interrelationship of the shields. These materials constitute only a small fraction by volume but cover a large part of the islands. Despite this, it is confirmed that the disposition of the shields is opposite to the insular progression induced by the hot spot, suggesting the presence of some SW-NE propagation volcanic front or fracture to explain its direction of development.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6641464">https://doi.org/10.6084/m9.figshare.c.6641464</jats:ext-link> </jats:p>

<jats:p> The Cenozoic development of the Scotia Sea and opening of Drake Passage led to the dispersal of crustal blocks of the North and South Scotia ridges that today have a strong influence on the pathway of the Antarctic circumpolar current. The pre-translation positions of the crustal fragments of the Scotia ridges are uncertain, with correlations to both the Antarctic and South American plates. We present direct geochronology ( <jats:sup>40</jats:sup> Ar/ <jats:sup>39</jats:sup> Ar) from Bruce and Jane banks of the South Scotia Ridge that yield Late Cretaceous – Paleogene ages indicating a pre-translation magmatic history. Basaltic magmatism from Bruce Bank is calc-alkaline, akin to Cenozoic magmatism of the South Orkney microcontinent and the South Shetlands Islands, and in agreement with pre-translation tectonic models that place the crustal blocks of the South Scotia Ridge adjacent to the northern Antarctic Peninsula arc. The intra-oceanic arc magmatism at Jane Bank is Late Cretaceous in age (97.2 ± 1.1 Ma), and is not consistent with models suggesting a Miocene origin as part of the ancestral South Sandwich arc. The development of westward-directed subduction adjacent to Jane Bank is predicted in some tectonic models as a consequence of Late Cretaceous plate dynamics that developed prior to the Oligocene – Miocene ancestral arc. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6639909">https://doi.org/10.6084/m9.figshare.c.6639909</jats:ext-link> </jats:p>

<jats:p> The upper gneiss unit is exposed in the northernmost Seve Nappe Complex (SNC) in the Scandinavian Caledonides. To investigate the Caledonian tectonic history of the unit, <jats:italic>in-situ</jats:italic> white mica and biotite <jats:sup>40</jats:sup> Ar/ <jats:sup>39</jats:sup> Ar geochronology was applied to a leucogranite and two paragneisses. The leucogranite exhibits low strain traits. Biotite porphyroblasts yielded a cooling age of 459 ± 2 Ma. White mica that replace biotite and plagioclase provided a crystallization age of 436 ± 5 Ma. White mica in both paragneisses exhibit high strain characteristics associated with top-to-E sense of shear. One paragneiss provided dispersed late Cambrian to Late Ordovician dates with the youngest approximating deformation at 459 ± 2 Ma. The older dates are interpreted to reflect <jats:sup>40</jats:sup> Ar inherited from a previous metamorphic event. The second paragneiss yielded a deformation age of 434 ± 2 Ma. The collective dataset is interpreted to record: 1) exhumation of the upper gneiss unit at c. 459 Ma, 2) deformation and fluid-infiltration at c. 434 Ma during continental collision. The events closely resemble the deformation histories of other northern SNC terranes. Synthesizing these results with other northern SNC terranes suggests that the Baltican margin underwent oblique, south-to-north subduction during late Cambrian time. </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Caledonian Wilson cycle collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/topic/collections/the-caledonian-wilson-cycle">https://www.lyellcollection.org/topic/collections/the-caledonian-wilson-cycle</jats:ext-link> </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6639993">https://doi.org/10.6084/m9.figshare.c.6639993</jats:ext-link> </jats:p>

<jats:p>The Santa Eulália Plutonic Complex is formed by two main granites, G0 and G1 granites. Within the G0 granite there are metasedimentary carbonate and pelitic rocks (roof pendants) and elongated masses of mafic-intermediate rocks (M-group). The host rocks comprise a diversified sequence of igneous, metasedimentary and metamorphic rocks. The study area is constrained by Variscan structures formed in a transpressional/transtensional sinistral tectonic regime – the Tomar-Badajoz-Córdoba sinistral shear zone, and is cut by the Alter do Chão and Assumar faults. The geological complexity of the area makes hard to determine the emplacement mechanism of the pluton. Herein, a model is proposed for the ascent and emplacement of the pluton; this model can also be applied to similar post-collision Variscan granites. The gravity anomalies suggest that the pluton is slightly asymmetric and extends to the south-southeast beneath the host rocks, and its main root has a thicknesses of more than 8 km in its deepest areas. Complementarly, the available radiometric data for an extended area embracing several regional plutons suggest a W-E magmatic alignment. The Variscan structures likely constituted efficient crustal discontinuities enabling the generation and ascent of magma. Our model involves a W-E magmatic axis for magma spreading along extensional fractures (T-fractures) related to the Tomar-Badajoz-Córdoba shear zone. The opening movement along these fractures, created divergent forces that allowed the ascent and emplacement of the plutonic rocks. The importance of these fractures is well represented by the outcrops of the porphyritic biotite granites (Ervedal, Fronteira and G1 granites).</jats:p>

<jats:p> We use seismic reflection data acquired by a winter-over expedition on drifting sea ice in the central Arctic Ocean to explore a possible spatial and temporal magmatic relation between the sub-bottom geology of part of the deep Arctic Ocean and the Mesozoic volcanic rocks found on the islands and the bordering continental shelf of Franz Josef Land and Svalbard? The new data set from the North American segment (85 <jats:sup>o</jats:sup> – 90 <jats:sup>o</jats:sup> N) of the Lomonosov Ridge, central Arctic Ocean documents several Mesozoic volcanic pulses over a distance of ˞600 km along the ridge. This volcanism borders a domain of high magnetic field intensity over the adjacent Alpha Ridge in the deep basin where the magnetic source rocks and recent seismic reflection data indicate extensive Mesozoic magmatism. We suggest the Mesozoic volcanism on the Lomonosov Ridge in its paleo-position at the former continental margin north of Franz Josef Land and Svalbard spatially link the Mesozoic magmatic pulses of the continental High Arctic Large Igneous Province (HALIP) of polar Europe to volcanism on the adjacent Alpha Ridge in the deep Arctic Ocean. Increased input of heat to the upper crust on the Lomonosov Ridge enhanced maturation of hydrocarbon source rocks as manifested by the presence of gas/fluid escape pipes restricted to the area of volcanism. </jats:p>