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<jats:p> Geologists have speculated when plate tectonics began since the dawn of that revolution, with recent estimates ranging from the last 20% of Earth history to within the first 5%. All such estimates rest on six types of evidence: preservation of modern plate tectonic features, detrital-zircon age spectra, trace element-isotope geochemistry, atmosphere-crust-mantle exchange, paleomagnetism, and model calculations. ‘Burke's Law’ suggests that the null hypothesis puts the onus on demonstrating when plate tectonics was <jats:italic>not</jats:italic> operating rather than requiring observation of plate tectonic features in the geologic record as assemblages presumed characteristic of plate tectonics could be lost from the geologic record (due to preservation biases) or never existed (due to secular changes). This issue has become salient as our community appears to be coalescing around the paradigm that plate tectonics began during the late Archean in the face of problematic evidence, much the same way it's done repeatedly over the past century (e.g., rejecting continental drift in preference to geosyncline theory). I summarize evidence from the six evidentiary types and conclude that we don't know when plate tectonics initiated. Claiming we do forestalls the day that we might truly understand an event at the heart of Earth history and habitability. </jats:p>

<jats:p>The fossils of the Lebanese Upper Cretaceous Lagerstätten, especially the articulated fish, are world renowned. Famous for their soft tissue preservation and highly sought after by fossil collectors, Lebanese fossils provide key information concerning the evolution of several major extant and extinct groups of Mesozoic organisms including cephalopods, crustaceans, hagfish, sharks, marine reptiles, pterosaurs, etc. In fact, fossils from Lebanon are so exceptional that historical documentation describing them extends back to the Roman Empire. However, despite over 1600 years of knowledge of these fossils, a thorough understanding of the depositional environments, taphonomy, and palaeoecology of the four main sites: Haqel, Hjoula, Nammoura (each Cenomanian in age), and Sahel Aalma (Santonian) is lacking. Here we compile a review of the palaeoenvironments, fauna, and flora of these four Lebanese Lagerstätten. Our synthesis outlines the history of fossil discovery, describes the current understanding of the geology, ages, mode of preservation, and organisms found at these four sites. We also undertake a bibliometric and holotype analysis to investigate the impact that scientific colonialism has had on Lebanon. Our data confirms that local Lebanese researchers are typically not included on publications pertaining to Lebanese fossils and that the majority of Lebanese type material is stored in large historical collections outside of Lebanon, predominantly in institutions within the northern hemisphere. Here, we recommend some basic practices for researchers utilising historical collections that can help develop local Lebanese fossil collections and establish more research opportunities for local palaeontologists.</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.7191547">https://doi.org/10.6084/m9.figshare.c.7191547</jats:ext-link> </jats:p>

<jats:p>Rocky shorelines form where basement highs are eroded and flooded during marine transgressive events. Despite the Mesozoic North Sea rift generated numerous platform margins and rotated fault blocks which acted as basement highs, rocky shoreline deposits have not been previously reported. In the rock record rocky shoreline deposits are usually represented by thin conglomerates overlying major unconformities, and are typically characterised by their ichnological aspects, rather than their depositional facies. This study uses the sedimentological aspects of modern and Miocene rocky shorelines from Spain and Austria, to create facies models which are then applied to the recognition of rocky shorelines in the Mesozoic of the Central North Sea. Our results demonstrate that structureless, clast-supported, poorly-to-moderately sorted conglomerate-breccia deposits are associated with competent basement lithologies, which produce hard, resistant coastal cliffs around previously overlooked volcanic centres in the subsurface of the North Sea. The basement lithologies in most of the Central North Sea favoured the formation of softer coastal cliffs, with less resistant lithologies that did not generate or preserve gravel size particles, being mostly characterised by low-angle, unconformity-bounded sandstone and fine-grained deposits and precluding the preservation and recognition of Mesozoic rocky shores in much of the North Sea's stratigraphic record.</jats:p>

<jats:p> Dating the timing of deformation within shear zones is critical to quantifying orogenic processes and developing time-resolved regional tectonic frameworks. Such work requires the integration of detailed microstructural analysis with <jats:italic>in situ</jats:italic> geochronology to quantify when deformation mechanisms were active at the micro-scale. The Proterozoic, granulite-facies Strangways Metamorphic Complex was exhumed during the Devonian to Carboniferous intracontinental Alice Springs Orogeny. New microstructural observations, quartz <jats:italic>c</jats:italic> -axis orientation analyses, mica chemistry, Ti-in-biotite thermometry, <jats:italic>in situ</jats:italic> mica Rb–Sr and titanite U–Pb geochronology outline a detailed history of ductile shearing across the complex. Movement along the north boundary shear zone of Strangways Metamorphic Complex appears to have initiated <jats:italic>c.</jats:italic> 382 Ma, preceding peak metamorphism in the area during the Alice Springs Orogeny. Widespread reverse-sense ductile shearing occurred within the Strangways Metamorphic Complex between <jats:italic>c.</jats:italic> 365 and 355 Ma, and correlates with rapid cooling of the region. Late-stage ductile deformation is recorded at <jats:italic>c.</jats:italic> 335 Ma, likely reflecting the terminal exhumation of the Strangways Metamorphic Complex. Finally, the new <jats:italic>in situ</jats:italic> muscovite and biotite Rb–Sr data collected herein permit comparison with previous two-point mica Rb–Sr isochrons and <jats:sup>40</jats:sup> Ar– <jats:sup>39</jats:sup> Ar dates from the same specimens. In the rocks analysed, the biotite Rb–Sr system returned dates similar to the previous <jats:sup>40</jats:sup> Ar– <jats:sup>39</jats:sup> Ar white mica dates, perhaps indicating a similar effective closure temperature. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Test results and previous geochronology data from the Alice Springs Orogeny are available in tabular form 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://osf.io/yjp24/?view_only=0bf5bec9f5c94a1aa4fb413320ec24e8">https://osf.io/yjp24/?view_only=0bf5bec9f5c94a1aa4fb413320ec24e8</jats:ext-link> </jats:p>

<jats:p> U–Pb apatite geochronology is increasingly recognized as a valuable tool for constraining the age of mid-crustal ductile shear zones. The crustal-scale Outer Hebrides Fault Zone (OHFZ) within the Laurentian foreland of the Scottish Caledonides has long been of uncertain age and tectonic significance. Earliest deformation within the OHFZ was associated with top-to-the-NW ductile thrusting that formed a belt of greenschist facies mylonites within host Archean−Paleoproterozoic basement gneisses. Previous estimates for the timing of thrusting vary between <jats:italic>c</jats:italic> . 1600 Ma and <jats:italic>c</jats:italic> . 430 Ma. The mylonitic fabrics are defined by a recrystallized assemblage of quartz + albite/oligoclase + sericite + actinolite + epidote + apatite ± calcite, consistent with deformation temperatures of 400–500°C and within the range of reported closure temperatures for Pb diffusion in apatite. U–Pb (LA−ICP−MS) dating of two texturally distinct apatite grain types within the mylonites has yielded ages mostly in the range <jats:italic>c</jats:italic> . 1100–900 Ma. The OHFZ is therefore interpreted as a Grenville–Sveconorwegian structure that formed during the tripartite collision of Laurentia, Baltica, and Amazonia and the assembly of Rodinia. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material</jats:bold> : U–Pb isotopic data (Table S1), trace element data (Table S2) and laser ablation spot images 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.7084925">https://doi.org/10.6084/m9.figshare.c.7084925</jats:ext-link> </jats:p>

<jats:p>Discoidal carbonaceous compressions are the most common type of Precambrian macrofossils with a long temporal range starting from the late Paleoproterozoic. However, their unsolved biological nature restricts our understanding of the early evolution of macroscopic life. Here we report an assemblage of well-preserved discoidal carbonaceous macrofossils from the early Mesoproterozoic Gaoyuzhuang Formation in North China, which provides insights into this problem. They are preserved in round to elliptical shapes with sizes ranging from millimeters to several centimeters. Petrographic thin sections show that the macrofossils consist of laminated structures with alternating organic matter along with clay minerals and dolomites. Neither cellular structures nor individual microfossils were identified within them, but their regular shape, internal structures, and associated mineral constituents suggest that they are probably remains of the microbial biofilms, rather than multicellular organisms. It presents a well-preserved fossil example of microbial biofilms with macroscopic size and regular overall morphology. It further implies a possible origin of microbial biofilm for some of the early carbonaceous macrofossils and calls for detailed reexaminations of those macrofossils to exclude such possibilities. Our finding is consistent with previous studies that biofilms may have played an important role in survival for early microorganisms in the Precambrian ecosystem.</jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the The North China Craton as a window to Earth’s middle age 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-north-china-craton-as-a-window-to-earths-middle-age">https://www.lyellcollection.org/topic/collections/the-north-china-craton-as-a-window-to-earths-middle-age</jats:ext-link> </jats:p>

<jats:p>The Earth is the only known planet where plate tectonics operates. We review features of Archaean and early Proterozoic geology that constrain tectonic environments and inform discussions of the onset of plate tectonics. There is the question of scale, and how the results of individual case studies are put into a wider global context. Global models may be difficult to test, and we seek to integrate evidence for plate tectonics being active with ancient records of subduction. We explore evidence for when the continental crust became rigid enough to facilitate plate tectonics, based on the occurrence of widespread dyke swarms and large sedimentary basins, relatively widespread granulite facies metamorphism, and evidence for crustal thickening. We argue that it remains difficult to constrain tectonic settings from contemporaneous metamorphic events without spatial control. Archaean cratons stabilised at different times in different areas from 3.1–2.5 Ga, juvenile continental crust changed from mafic to more intermediate compositions, there was a reduction in crustal growth at ca. 3 Ga, and increasing evidence for lateral movement of crustal fragments. These with the other changes at the end of the Archaean are taken to reflect the onset of plate tectonics as the dominant global regime.</jats:p>

<jats:p>The Cenozoic uplift of the Qilian Shan is intimately connecting with the collision of India and Eurasian Plates, while the deformation mechanism is still a mystery for its far distance from the collision boundary. The first requirement for answering this question is to obtain the uplift process of this range, which remains debate. In this study, we compiled apatite fission track data from previous studies on the range, aims to reveal the spatial and temporal disparities or similarities for the exhumation process. Most age-evolution profiles and thermo-modeling results show a low exhumation rate during 80-20 Ma, corresponding to shorter track lengths, indicating a lower erosion rate and lower relief across the whole Qilian Shan region. The result also reveals two stages of rapid exhumation, during Cretaceous (120-80 Ma) and since Miocene (20-0 Ma). The exhumation history of the Qilian has no significant spatial difference, and the outward growth was limited at the southern and northern edge after 5 Ma. This temporal and spatial pattern for the exhumation of the Qilian Shan suggests that there was probably no obvious uplift at the initial collision of India-Tibet plates, and support the proposal that the whole Qilian range uplifted synchronously since 20 Ma.</jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Mesozoic and Cenozoic tectonics, landscape and climate change 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/mesozoic-and-cenozoic-tectonics-landscape-and-climate-change">https://www.lyellcollection.org/topic/collections/mesozoic-and-cenozoic-tectonics-landscape-and-climate-change</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.7224863">https://doi.org/10.6084/m9.figshare.c.7224863</jats:ext-link> </jats:p>

<jats:p>The Tarim Craton (NW China) is a significant archive of tectonic events during the assembly and breakup of the Precambrian Supercontinents Columbia and Rodinia. It provides a comprehensive record of crustal development during the Proterozoic. In this paper, we review and synthesize the magmatic, metamorphic, and stratigraphic records of the Precambrian Tarim and delineate the geochronology of significant geological events that led to the formation of this major cratonic block. The extant geophysical and geological data show that the Tarim Craton consists mainly of the South and North Tarim blocks. The record of late Paleoproterozoic tectono-thermal events is well displayed in and across the craton, involving the amalgamation of these two blocks to form its unified crystalline basement during the Columbia buildup. However, the record of mid-Neoproterozoic events during the Rodinia assembly is only exposed around its periphery. The Proterozoic record of the craton includes the Mesoproterozoic–early Neoproterozoic low-grade metamorphic rock units and a late Neoproterozoic sedimentary cover. The early Mesoproterozoic stratigraphy in the SW, NE, and SE parts of the Tarim suggests a period of tectonic stability following the amalgamation of the North and South Tarim blocks in the late Paleoproterozoic, indicating the completion of its cratonic buildup.</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.7225059">https://doi.org/10.6084/m9.figshare.c.7225059</jats:ext-link> </jats:p>

<jats:p>Arcuate traces of large structures characterize many mountain chains. The Variscan Belt is not an exception, and depicts one of the tightest oroclines in the Earth, the Ibero-Armorican Arc, as well as more open ones in the Eastern Moroccan Meseta, Central Iberia, French Massif Central and the Bohemian Massif. All Variscan arcs are considered true or secondary oroclines, and are late orogenic features, but their timing and deformation mechanisms differ. Models explaining their origin have been proposed for some individual arcs, and are generally controversial. This contribution aims at interpreting the ensemble of Variscan arcs highlighting their age relative to previous orogenic features as well as to those associated with arc development. Several mechanisms operated to form the arcs, the most important being ductile transcurrent shearing and rigid-plastic indentation, with shortening parallel to the orogen playing a secondary role. These mechanisms acted at different time intervals, their participation or relative importance differs for each arc and they gave rise to distinct associated structures. The development of the arcs is viewed as related to late Variscan dextral transpression provoked by displacement of Laurussia to the E relatively to Gondwana during the Serpukhovian to early Permian.</jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Processes of Pangea construction 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/processes-of-pangea-construction">https://www.lyellcollection.org/topic/collections/processes-of-pangea-construction</jats:ext-link> </jats:p>