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<jats:p>It remains unclear whether large-scale polyphase displacement along strike-slip faults is associated with tip propagation, and how the tip-damage zones of these faults respond to intracontinental block movements. Damage structures around the southern tip of the 2400-km-long Tan–Lu fault zone (TLFZ) in eastern China provide an ideal opportunity to investigate deformation mechanisms at the tip of an intracontinental strike-slip fault. Structural and geochronological data from the southern Zhangbaling uplift within the TLFZ show that following the Triassic initiation of the fault, two phases of sinistral faulting occurred: an earlier phase at the beginning of the Early Cretaceous and later phase between the Early and Late Cretaceous. The early sinistral structures are expressed by ductile shear zones in the southern Zhangbaling uplift, whereas the younger sinistral structures are expressed as shear zones in the north and brittle faults in the south. Zircon U–Pb dating results for felsic gneiss of the TLFZ suggest that ∼200 km of cumulative displacement occurred during the Cretaceous and was restricted to wall rocks on the western side of the fault. The southern tip of the TLFZ remained fixed during the displacement, and the dilational quadrant associated with the fault is interpreted to have been stationary. The current ∼400 km of sinistral offset of the Dabie and Sulu orogens represents the original offset caused by the Triassic collision of the North China Craton and South China Block. The two phases of sinistral motion were induced by two phases of compression along the ∼460-km-long contractional quadrant, which was dominated by thrusting along pre-existing faults as well as fault-related folding and uplift. Damage structures at the southern tip of the TLFZ show that large-scale polyphase strike-slip motion may be associated with a fixed fault tip, hundreds of kilometers of displacement can be restricted to one side of a major fault, and displacement can be accommodated by thrusting along pre-existing faults in the contractional quadrants.</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.6368850">https://doi.org/10.6084/m9.figshare.c.6368850</jats:ext-link> </jats:p>

<jats:p> Basement-hosted fissure fill networks in sub-unconformity settings are increasingly recognised globally and have the potential to act as important sub-surface reservoirs and/or migration pathways for hydrocarbons, geothermal fluids and groundwater. In the present paper we examine well exposed fissures from exhumed crystalline upper Carboniferous basement rocks in southern Italy (Calabria) and describe their nature, origin and evolution. The basement rocks record the emplacement and exhumation of their plutonic protoliths, and an evolution which includes initial intrusion in the upper Carboniferous followed by veining, folding, and rifting events to eventual exhumation at the surface when fissuring occurred in the mid-Miocene. The fissure network hosts fossiliferous marine sediments, wall rock collapse breccias and limited mineralization with vuggy cavities. In the basement below the main erosional unconformity, fissure fills form up to 50% by volume of the exposed rock. The fills are notably porous (up to 15-25% matrix porosity) compared to the ultra-low porosity (&lt; 1%) of the crystalline host rocks. We present field observations, palaeostress analyses of fault slickenlines, and fracture topology analyses which demonstrate that these exceptionally well-connected fissure networks are related to rifting and penetrated to depths of <jats:italic>at least</jats:italic> 150 m below the main Miocene erosion surface. </jats:p>

<jats:p> Active graben systems in south Tibet and the Himalaya are the surface expression of ongoing east–west extension, although the cause and spatiotemporal evolution of normal faulting is a still a matter of debate. We reconstructed the exhumation history driven by normal faulting in the southern Tangra Yumco graben using new thermochronological data. The Miocene cooling history of the footwall of the main graben-bounding fault is constrained by zircon (U–Th)/He ages (16.7 ± 1.0 to 13.3 ± 0.6 Ma), apatite fission track ages (15.9 ± 2.1 to 13.0 ± 2.1 Ma) and apatite (U–Th)/He ages (7.9 ± 0.4 to 5.3 ± 0.3 Ma). Thermo-kinematic modelling of the data indicates that normal faulting began 19.0 ± 1.1 Ma at a rate of <jats:italic>c.</jats:italic> 0.2 km myr <jats:sup>−1</jats:sup> and accelerated to <jats:italic>c.</jats:italic> 0.4 km myr <jats:sup>−1</jats:sup> at <jats:italic>c.</jats:italic> 5 Ma. In the northern Tangra Yumco rift, remodelling of published data shows that faulting started <jats:italic>c.</jats:italic> 5 myr later at 13.9 ± 0.8 Ma. The age difference and the distance of 130 km between these two sites indicates that rifting and normal faulting propagated northward at an average rate of <jats:italic>c.</jats:italic> 25 km myr <jats:sup>−1</jats:sup> . As this rate is similar to the Miocene convergence rate between India and south Tibet, we argue that the under-thrusting of India beneath Tibet exerted an important control on the propagation of rifts in south Tibet. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material</jats:bold> : Figures S1, S2, and Table S1 with details on apatite fission track analysis 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.6198584">https://doi.org/10.6084/m9.figshare.c.6198584</jats:ext-link> </jats:p>

<jats:p> Despite the modern celebrity of the fossil collector Mary Anning (1799–1847) of Lyme Regis and her frequent use as an icon in scientific education and popularization, there are few accounts of her life by her contemporaries. We report here a previously unpublished anonymous manuscript memoir of Anning's life, in the Special Collections of the University of Bristol Library. Evidence from textual analysis and handwriting corroborates its attribution to George Roberts (bap. 1804–60) of Lyme Regis, schoolmaster and historian. He wrote it at some time during 1837–47, perhaps 1839–47, by adapting a passage in his 1834 history of Lyme Regis. It was apparently intended for a new book, but was altered into an obituary after Anning's death. Evidence is presented that Roberts wrote the obituary of Anning in the <jats:italic>Athenæum</jats:italic> , which was widely republished in newspapers. Henry De la Beche (1796–1855) published another obituary in the <jats:italic>Proceedings of the Geological Society</jats:italic> . Roberts helped him to obtain information from Anning's family, but did not use this new information in his manuscript. Benjamin J.M. Donne (1831–1928), a former pupil of Roberts, painted the Society's portrait of Anning. A claim that it was commissioned by a group, mostly Fellows of the Society, remains unconfirmed. </jats:p>

<jats:p> A basinally isolated breccia–pebbly sandstone couplet occurs in the axial part of the latest Jurassic rift-climax half-graben in Wollaston Forland, East Greenland. Synrift breccias are otherwise restricted to a narrow zone along the scarp of the basin-margin Dombjerg Fault. Towards the north the Dombjerg Fault sidesteps <jats:italic>en echelon</jats:italic> towards the east where it continues in the Thomsen Land Fault. The breccia part of the couplet was transported by a noncohesive debris flow and the pebbly sandstone by a high-density turbidity flow. The couplet is located about 15 km east of the Dombjerg scarp and flowed southwards along the half-graben axis. It is interpreted to have been derived from the southern end of the Thomsen Land Fault. This gives a runout distance of at least 25 km. Other isolated breccias have been reported towards the south along the half-graben axis, giving a runout distance of up to 40 km along the roughly horizontal half-graben axis. The angularity of the clasts is remarkable and reflects derivation directly from the fault scarp during a single catastrophic event. The occurrence of breccias thus cannot be taken as evidence of short transport and deposition at the foot of a scarp or steep slope. </jats:p>

<jats:p> The sediments in two stacked megafans in the Owambo Basin of northern Namibia and southern Angola were made accessible by a <jats:italic>c.</jats:italic> 400 m long, continuously cored borehole. Previous studies have indicated that the lower buried Paleocene–Eocene Olukonda Megafan was deposited by a palaeo-Kunene River transporting material from the NW (i.e. from the Kunene Intrusive Complex and the adjacent Angola Shield). The morphology of the overlying Eocene–Pliocene Cubango Megafan suggests the input of sediments from the north via the Cubango River. Mineralogical and geochemical data from the upper fan indicate felsic metamorphic and granitoid sources. Previous studies, however, did not provide a unique provenance identifier. Combining detrital zircon U–Pb data from both megafans with previously published and newly obtained mineralogical and geochemical data confirms two distinct provenances. The Olukonda Megafan can now be uniquely attributed by means of its detrital zircon ages to the Kunene Intrusive Complex and the surrounding Epupa Metamorphic Complex. In good agreement with the geochronologically more varied geology of the source region in the north, the Cubango Megafan detrital zircon record shows a wide distribution of Paleoproterozoic to Archean ages, but also a younger age range, probably related to a later Damaran/Pan-African source, which is absent in the Olukonda detrital zircon record. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Data obtained for this study, e.g. geochemical data, heavy mineral composition, heavy mineral morphology, zircon morphology, U-Th-Pb isotopes and ages on zircon, instrument settings, and U-Th-Pb isotope data of analysed reference zircon 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.6280517">https://doi.org/10.6084/m9.figshare.c.6280517</jats:ext-link> </jats:p>

<jats:p>A geochronological study of the St Georgen tuff, favourably positioned within the Middle Miocene marine succession of the Vienna Basin, is essential to our understanding of the timing of the middle Badenian transgression. We report here new data on the separated zircon U–Pb ages/phase chemistry and the clay mineralogy of altered tuffs and then use these data to infer the provenance of the tephra and the palaeoenvironmental conditions. The ages of the tuff range between 15.78 ± 0.27 and 14.36 ± 0.31 Ma, with a weighted mean age of 14.59 ± 0.2 Ma. This defines the onset of the second Badenian transgression in the Central Paratethys region, which was the strongest transgression in the entire Miocene record of the Vienna Basin. The compositional and temporal relationships between the tuff and the neighbouring volcanism suggest that the Harsány eruption in the central Pannonian Basin is the most plausible source region for the tephra. West- and SW-directed tropospheric trade winds or easterlies were responsible for the transport of the Harsány tephra to its present location. The prevalence of halloysite, in addition to post-depositional alteration reactions (glass–smectite–halloysite and kaolinite–halloysite) suggest the fallout of tephra in a very shallow sea, which may have been affected by seasonal wetting and drying cycles at the onset of ash deposition.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Halloysite mineralogy, global geochemistry and U-Pb zircon age data 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.6294944">https://doi.org/10.6084/m9.figshare.c.6294944</jats:ext-link> </jats:p>

<jats:p>The ENE-WSW-trending Møre-Trøndelag Fault Complex (MTFC) in Central Norway is a 10-50 km-wide, steeply dipping reactivated fault zone. Onshore, it transects Devonian sedimentary rocks and a series of E to SE transported metamorphic nappes, which were emplaced during the Scandian (Silurian-Devonian) Orogeny. Offshore, the MTFC defines the southern margin of the Møre Basin and the northern margin of the Viking Graben, meaning that the fault complex played a major role in controlling the architecture of these Mesozoic basins. Onshore, the MTFC has had a prolonged and heterogeneous kinematic history. The complex comprises two major fault strands: the Hitra-Snåsa Fault (HSF) and the Verran Fault (VF). These two faults seem to have broadly initiated as part of a single system of sinistral ductile shear zones during the early Devonian (c. 410 Ma). Sinistral transtensional reactivation (Permo-Carboniferous; 290 Ma) of the ENE-WSW-trending HSF and VF led to the development of cataclasites and pseudotachylites together with the formation of N-S-trending faults establishing the present-day brittle fault geometry of the MTFC. Later phases of Mesozoic reactivation focused along the Verran Fault Zone (VFZ) and N-S-linking structures were likely related to mid-late Jurassic/early Cretaceous rifting and late Cretaceous/early Cenozoic opening of the North Atlantic.</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.6390518">https://doi.org/10.6084/m9.figshare.c.6390518</jats:ext-link> </jats:p>

<jats:p>The Hølonda area of the central Scandinavian Caledonides is a key for models of the Caledonian orogen due to its Ordovician fauna of Laurentian affinity, now stranded on the Baltic side during opening of the North Atlantic. Here, we present a revised stratigraphic and tectonomagmatic model based on remapping, sedimentology, igneous geochemistry, Nd and Sr isotopes, and geochronology. The Hølonda Group (c. 470–461 Ma) reflects a transition from subaerial and shallow-marine deposition on a continental shelf, to deeper-water sedimentation along a subsiding slope. Adakitic and MORB-type magmatism at c. 468 Ma was succeeded by benmoreitic–rhyolitic, shoshonitic, calc-alkaline, and ultra-alkaline volcanism at c. 467–465 Ma. The complex magmatism followed arc–continent collision along a microcontinent outboard of Laurentia, associated with subduction polarity flip and slab rollback. This led to rifting and opening of a wide basin and its adjoining shelf on thickened orogenic lithosphere. Associated mantle upwelling and partial melting of depleted and variably metasomatized mantle occurred in a tectonomagmatic setting comparable to that of the central Mediterranean. The Hølonda–Ilfjellet setting is unique along the Caledonian–Appalachian orogen, possibly reflecting interaction with Laurentia-derived continental terranes at the northeastern end of the Taconian–Grampian orogenic tract.</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.6368922">https://doi.org/10.6084/m9.figshare.c.6368922</jats:ext-link> </jats:p>

<jats:p> The prevalence of antecrysts in arc volcanic rocks is widely accepted, yet the origin of their carrier melts remains debated. Crystal cargo in lava flows from Taranaki volcano, New Zealand, is dominated by plagioclase, clinopyroxene, and amphibole. Except for some crystal rims, mineral phases are in disequilibrium with the melt they are entrained in. Major element chemistry reveals an almost complete compositional overlap between the crystals in the lava and those in xenoliths. The large volume fraction of crystals (35–55 vol%) exerts a strong control on whole-rock compositions, reducing silica by 5–11 wt% compared to the carrier melt. Yet there is no clear relationship between mineral proportion and bulk rock compositions. Our data are inconsistent with extensive fractional crystallization, commonly invoked as a driver of magma evolution towards silica-rich compositions. Instead, high-temperature, aphyric carrier melts with varied compositions (55–68 SiO <jats:sub>2</jats:sub> wt%) entrain crystal cargo while ascending through colder, low-silica rocks. Thus, some primary melts at Taranaki volcano are significantly more silica-rich than arc basalts commonly invoked as parental magmas. Further, thermometric and hygrometric constraints preclude a deep crustal hot zone for the source of these melts, which we argue are of subcrustal origin. </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.6406813">https://doi.org/10.6084/m9.figshare.c.6406813</jats:ext-link> </jats:p>