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<jats:p>The Upper Jurassic – Lower Cretaceous interval represents a prolonged marine deoxygenation period particularly in the Boreal–Arctic basins, the controlling factors of which remain poorly understood. Two drill cores totaling &gt;450 m cover the Kimmeridgian–Barremian succession in contrasting locations in an evolving half-graben system (basin center and near the footwall crest) in Wollaston Forland, NE Greenland; they provide an exceptional ∼20 myr long window into paleoenvironmental development and changes in redox conditions within a detailed tectonostratigraphic framework. Synthesis of a multidisciplinary dataset including sedimentology, inorganic and previously published organic geochemistry indicates that, despite continuous black mudstone accumulation from the Kimmeridgian to the Ryazanian, sea floor anoxia was intermittent in the Kimmeridgian, whereas more sustained anoxia/euxinia occurred in the middle Volgian – early Ryazanian. Correlation to reported contemporaneous successions along the Greenland margin, indicate that protracted rifting and generation of localized sea-floor topography were among the major drivers both of sea-floor deoxygenation and current funneling and amplification during the Jurassic–Cretaceous transition. Consequently, distribution of seaway current activity and dysoxia, anoxia and euxinia varied spatially, allowing fully oxygenated and anoxic pockets to coexist.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> [S1: Facies table, S2: Summary of geochemistry data, S3: Geochemistry raw data, S4: Sedimentological log from Store Koldewey] is 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.6442539">https://doi.org/10.6084/m9.figshare.c.6442539</jats:ext-link> </jats:p>

<jats:p>The island of Foula located 25 km SW of Shetland preserves a gently folded, 1.6 km thick sequence of Middle Devonian sandstones spectacularly exposed in kilometre-long cliff sections over 350 m high. These rocks unconformably overlie likely Precambrian-age amphibolite facies basement rocks, intruded by sheeted granites. The onshore succession is similar in age to the nearby Lower Clair Group offshore to the west. New mapping which incorporates use of drone imagery in inaccessible cliff sections uses down-plunge projections to show that growth folding and faulting on Foula were contemporaneous with sedimentation during basin filling. The large-scale structural geometry is consistent with regional constrictional strain due to sinistral transtension associated with movements along the Walls Boundary - Great Glen Fault Zone system during the Middle Devonian. Detrital zircon provenance studies indicate that the Devonian sequences of Foula - and nearby Melby in western Shetland - show similarities with the Clair Group and Orkney successions. We suggest that NE-SW transtensional fold development contemporaneous with regional subsidence may be more widespread than previously realised in the Devonian basins of Scotland. Large, kilometre-scale folds previously interpreted to be related to Permo-Carboniferous inversion may therefore have initiated earlier in the basin evolution than previously realised.</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.6442552">https://doi.org/10.6084/m9.figshare.c.6442552</jats:ext-link> </jats:p>

<jats:p> This study focusses on new clumped isotope data from concretionary calcite cements in the Middle Jurassic Valtos Sandstone Formation (Great Estuarine Group) of the Inner Hebrides. Clumped isotopes show that concretion cementation began at 45±6 °C increasing to temperatures in excess of 70 °C before cooling slightly to 57 ± 7 °C at the concretion margin. In the early stages of cementation, calculated δ <jats:sup>18</jats:sup> O <jats:sub>FLUID</jats:sub> values were ∼ –12‰ VSMOW, identical to an estimate of Paleocene Hebridean meteoric water based on hydrothermal reactions close to Paleocene Igneous Centres. These δ <jats:sup>18</jats:sup> O <jats:sub>FLUID</jats:sub> values imply that concretion cementation started in the Paleocene probably during the earliest stages of phreato-magmatic effusive igneous activity. As the concretion grew, temperature changes were accompanied by progressively evolving δ <jats:sup>18</jats:sup> O <jats:sub>FLUID</jats:sub> compositions up to +2.1 ± 1.1‰ VMOW. These evolving δ <jats:sup>18</jats:sup> O <jats:sub>FLUID</jats:sub> compositions were caused by isotope exchange reactions between <jats:sup>18</jats:sup> O-rich lithologies and hot basinal fluids migrating upward along faults. This fluid flow was driven by progressive crustal loading from the thickening Paleocene lava pile which also caused sandstone compaction. Published radiometric dates that constrain the emplacement time of the Skye Lava Group, and its subsequent rapid erosion, suggest that concretion formation and final compaction was completed in no more than 2.6 myr, far more rapidly than modelled previously. Initial concretion growth that pre-dates development of volcanic topography shows that the strongly negative compositions of Hebridean Paleocene meteoric water are mainly of latitudinal rather than orographic origin. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Clumped isotope data correction and uncertainties, sample details and additional figures is 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.6459860">https://doi.org/10.6084/m9.figshare.c.6459860</jats:ext-link> </jats:p>

<jats:p> The tommotiids are an important group of Cambrian small shelly fossils, primarily retrieved from the carbonate rock by acid process. Herein, the abundant isolated sclerites of <jats:italic>Tannuolina</jats:italic> are recovered from the siltstone-dominated upper part of the Hazira Formation in the eastern Hazara Basin, North Pakistan. This discovery of tommotiids preserved in the siltstones not only suggests their occurrences in a variety of sedimentary lithofacies, but also provides the opportunity to look for the sclerites or scleritomes (even soft-tissue) of tommotiids in much wider taphonomic windows. The sclerites include two morphs, i.e. mitral and sellate types. Through morphological comparison, they can be identified as <jats:italic>Tannuolina zhangwentangi</jats:italic> Qian &amp; Bengtson, 1989. The large mitral and sellate sclerites (about 1 cm) illustrated herein manifest a relatively consistent morphology during the size increasement. The sellate sclerites may contain two sub-types, the larger sellate sclerite with sella on the sellate side and the smaller convex sellate side without sella on either sides. In the original scleritome, the two sub-types of sellate sclerites probably combine as a composite with the duplicatural side of the smaller one attached on the sella area of the large one. For the first time, <jats:italic>T. zhangwentangi</jats:italic> has been recovered from the Indian subcontinent, previously unknown outside South China. The middle and upper part of the Hazira Formation exclusively bearing <jats:italic>T. zhangwentangi</jats:italic> can directly invite correlation with the <jats:italic>S. flabelliformis</jats:italic> – <jats:italic>T. zhangwentangi</jats:italic> Assemblage Zone of South China representing the uppermost Cambrian Stage 2. This new palaeontological finds not only signifies the utility of <jats:italic>T. zhangwentangi</jats:italic> for intercontinental biostratigraphical correlation, but also suggests that the Terreneuvian SSF biostratigraphy between the Indian subcontinent and South China are quite consistent, comprising of three (at least two) correlative SSF Assemblage Zone (Zone Ⅰ, possible Ⅲ, and Ⅳ of South China). Additionally, our result may also support a relatively close palaeogeographical linkage between these two regions in early Cambrian. </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Advances in the Cambrian Explosion 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/advances-in-the-cambrian-explosion">https://www.lyellcollection.org/topic/collections/advances-in-the-cambrian-explosion</jats:ext-link> </jats:p>

<jats:p> Southern Türkiye faced widespread catastrophic destruction by two devastating earthquakes on the same day. As the earthquakes occurred at 04:17 (Mw=7.7, Pazarcık, Kahramanmaraş) and 12:30 (Mw=7.6, Elbistan, Kahramanmaraş) on February 6, 2023, neighboring active fault systems were broken in succession between the Hatay and Malatya Provinces in the region. The first earthquake, one of the largest earthquakes in this region during the last century, caused widespread damage to infrastructure and buildings, and produced large scale seismo-gravitational surface deformation such as landslides, lateral spreading, liquefaction and also extensional cracks. Here, we present the surface rupture geometry and coseismic displacement characteristics of the fault systems, determined with field observations immediately after the February 6, 2023 Pazarcık (Kahramanmaraş, Türkiye) earthquake (Mw=7.7). Preliminary results show that the total rupture length (L <jats:sub>max</jats:sub> ) is 270±10 km on the Karasu, Pazarcık and Erkenek segments of the East Anatolia Fault Zone. Left-lateral strike-slip faulting is developed with a maximum horizontal displacement (D <jats:sub>max</jats:sub> ) of 7.30 m and an average displacement (D <jats:sub>avg</jats:sub> ) of 3.00 m. Although the surface rupture generally exhibits a narrow deformation zone width of 2-5 m, it expands up to 50 m in some sections of the faults. Our implications for rupture dynamics suggest that fracture development started on a secondary fault (Narlı Fault), transferred to the main fault and triggered the breaking of asperities on Pazarcık segment which exhibits a long period accumulation of stress to initiate the major rupturing. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Figures S1 – S12 with details on coseismic displacement 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.6487245">https://doi.org/10.6084/m9.figshare.c.6487245</jats:ext-link> </jats:p>

<jats:p>The Indo-Myanmar Ranges (IMR) are an enigmatic mountain belt that occupy a complex tectonic zone in western Myanmar extending from the northern continuation of the active Sunda-Andaman arc into the eastern Himalayan syntaxis. The IMR are part of an accretionary fore-arc basin-arc complex that includes the Central Myanmar Basin and the Wuntho-Popa Arc to the east. New biostratigraphic, petrologic, and detrital zircon U-Pb age data are presented that are used to test and refine the divergent tectonic models that have been proposed for western Myanmar. These data suggest: 1) that the Upper Triassic Pane Chaung Formation was originally deposited adjacent to the NE Indian continental margin within northern Gondwana during the Late Triassic, and 2) that the Upper Cretaceous – Paleogene rocks of the IBR were mainly derived from the Wuntho-Popa Arc and Inner Belt, with a subordinate input from a crustal source, potentially from the Naga metamorphic-type Paleozoic basement. The Kalemyo ophiolite has an Early Cretaceous age similar to ages of ophiolites in the Indus Yarlung-Tsangpo suture zone, south Tibet and Nagaland, reinforcing the hypothesis that they were once part of the same Neo-Tethyan ocean floor.</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.6487105">https://doi.org/10.6084/m9.figshare.c.6487105</jats:ext-link> </jats:p>

<jats:p>New geological, structural, microstructural, and K-Ar biotite and illite geochronological data of igneous-metamorphic rocks exposed in the Cuesta de Rahue Basement Inlier are presented to reconstruct the Late Palaeozoic to Mesozoic tectonometamorphic and magmatic history of northwestern Patagonia. This block comprises a medium-grade metasedimentary sequence (Cuesta de Rahue Metamorphic Complex), Late Carboniferous granitoids and a low-grade metavolcano-sedimentary unit (Arroyo Coloco Metamorphic Complex). The Cuesta de Rahue Metamorphic Complex was deposited during the middle Palaeozoic and underwent Devonian low-pressure regional metamorphism, succeeded by the intrusion of granitoids at ca. 300 Ma. On the other hand, the Arroyo Coloco Metamorphic Complex record deformation and metamorphism at epizonal conditions (&gt; 300 °C), constrained at ca. 232-199 Ma by K-Ar and XRD illite data. The Cuesta de Rahue Basement Inlier thus records a protracted orogenic evolution, recording Devonian metamorphism, Late Carboniferous-Permian Gondwanide tectonomagmatic processes, and Late Triassic deformation and metamorphism. Afterwards, this block was also affected by Mesozoic normal faulting and, finally, by Miocene-Pliocene Andean deformation. The latter was intimately related to reactivation of inherited basement fabrics, favouring a transpressional deformation regime.</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.6484467">https://doi.org/10.6084/m9.figshare.c.6484467</jats:ext-link> </jats:p>

<jats:p>Koglin et al. (2022) present valuable new isotopic and field data regarding northwest Spitsbergen's tectonic history, and propose the existence of the Germaniahalvøya terrane with Scandian (Late Caledonian) igneous activity and deformation. Within this terrane, the Lerner Deformation zone (LDZ), is cast as an east-directed thrust, with the Liefdefjorden Migmatite Complex in the footwall and Lenerøyane Group meta-sediments above. The LDZ occurs on the west limb of the major, shallowly north plunging, Bockfjorden anticline. We suggest their data supports the unmentioned and discussed idea (Dallmann &amp; Piepjohn 2018, Braathen et al. 2018) that a Scandian metamorphic core complex exists here and that the LDZ is part of the Keisarhjelmen extensional detachment (Braathen et al. 2017, Maher et. al. 2022). The detachment consists of ductile to brittle, retrogressive, fault rocks up to several hundred meters thick along the contact between metamorphic basement and overlying Devonian basin strata. In addition, we note that Koglin et al's (2022) evidence for Scandian activity is consistent with core complex dynamics.</jats:p>

<jats:p>On the 06th February 2023, an earthquake with magnitude ∼Mw7.0 on the Narlı Fault, a fault subparallel to the East Anatolian Fault Zone (EAFZ), initiated a chain of large earthquakes on the EAFZ. The earthquakes occurred in a seismic gap with low geodetic strain rates, low background seismicity, where deformation is distributed across a wide fault zone and long recurrence time of historical earthquakes. The ∼50 km long rupture of the Narlı Fault towards Pazarcık, led to Mw7.8 left-lateral strike-slip earthquake breaking ∼300 km section of the ∼600 km long EAFZ bilaterally with a total duration of more than 80 s. Toward the southwest, the rupture propagated on ∼100 km long Amanos segment with a peak surface offset of 5 m, before diminishing toward the Hatay graben. In the northeast direction, the rupture reached a peak surface offset of 7 m before sharply declining at the termination of the 2020, Mw6.8 Sivrice earthquake rupture. A second large earthquake with Mw7.6 occurred 9 hours later on the Çardak Fault, located at the western margin of (and sub-parallel to) the EAFZ breaking the surface with almost 9 m left-lateral slip (average of ∼4 m). Following these large earthquakes, the increase in the regional stress led to a rapid seismic activation in a broad region from central to eastern Anatolia loading the faults at various scales and increasing seismic hazard. Two weeks after the initiation of the seismic crisis, a third earthquake with Mw6.4 occurred at the southern boundary of the Hatay graben, near the southwestern termination of the Amanos rupture. The earthquakes caused significant loss of human life, devastating 12 cities. We evaluate the observations prior to the ruptures, present preliminary seismological results with surface displacements from sub-pixel correlation of optical satellite images and the stress perturbations computed on the nearby faults based on preliminary slip models. The reevaluation of the seismic potential in light of the recent and historical earthquakes provides some new insight on seismic hazard assessment. The recent series of events on the EAFZ is an important reminder that large faults can generate very large earthquakes of multiple segments. The seismic potential of large earthquakes on these fault zones can only be estimated by considering multiple seismic cycles, and moment deficits from very large earthquakes.</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.6567094">https://doi.org/10.6084/m9.figshare.c.6567094</jats:ext-link> </jats:p>

<jats:p>High resolution correlations between boreholes are commonly based on a combination of geophysical well log data and biostratigraphy and, when these conflict, resolution can be contentious and difficult. Such a situation exists in the Middle Turonian chalks of the Anglo-Paris Basin, where electrical resistivity logs, registering thin but seemingly laterally continuous beds of clay-rich chalk (marls) in mostly uncored boreholes, provide apparently straightforward correlations across broad regions. In contrast, detailed biostratigraphical analysis using microcrinoids provides very different results, showing the presence of a major hiatus associated with a hardground and differing significantly from the geophysical correlations. Detailed re-examination of this contentious problem, utilising exposures adjacent to boreholes, demonstrates the supremacy of detailed biostratigraphical analysis, independently supported by regional thickness patterns, cyclostratigraphy and geochemistry. Although closely spaced geophysical well logs can afford convincing correlations, their use in correlation over broader geographical regions leads to erroneous and misleading conclusions.</jats:p>