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<jats:p> Giant sand injection complexes and localized swarms of sandstone intrusions are common in Upper Cretaceous to Miocene sedimentary successions of the Central and Northern California within a distance of less than 100 km from the Pacific margin of the North America Plate. One of the best preserved and extensively exposed injection complexes is the late Eocene Tumey Giant Injection Complex. The emplacement of sand injectites was driven by overpressure generated by thermal diagenesis of biosiliceous and smectite-rich mudstone host-rocks. The orientation and size distribution of sandstone intrusions was controlled by stress in which <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>σ</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>1</jats:sub> and <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>σ</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>3</jats:sub> were horizontal and, respectively, parallel and perpendicular to the present trace of the San Andreas Fault, and <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>σ</mml:mi> </mml:math> </jats:inline-formula> <jats:sub>2</jats:sub> was vertical. A strike-slip tectonic regime is inferred. Our analysis documents margin orthogonal extension and draws support for a late Eocene phase of increase of strain, and possibly active slip, along a syn-subduction strike-slip fault zone. Comparison with other injection complexes in the region indicates that the near-field maximum principal stress rotated through time, from normal to parallel with respect to the plate margin, probably in relation to variations of the relative motion vector of the converging plates. </jats:p>

<jats:p> When did Plate Tectonics begin on Earth, and what preceded it? Published thermo-mechanical mantle evolution models imply that the early history of planets with a composition and size similar to Earth and Venus should be characterized by periodic mantle overturns of 30-100 million years duration, separated by stable lid phases of 100-300 My. I argue this is best described as an Unstable Stagnant Lid, because this term captures the Jekyll-and-Hyde duality of such worlds, which alternate between a Stagnant Lid <jats:italic>ss</jats:italic> phase between mantle overturns, and a Mobile Lid phase during overturns. Mantle overturn upwelling zones would rework and resurface large tracts of pre-existing Hadean crust and basalt-dominated Archean-Style Oceanic Lithosphere (ASOL). Basal anatexis of ASOL ∼40-50 km thick (or melting within down-drips) could generate tonalite-trondhjemite melts (TTGs) and create proto-continental nuclei, while garnet pyroxenite restites delaminate into the mantle. With further reworking, low-K tonalitic rocks would remelt to produce granodiorite and granite, completing the transfer of radioactive elements out of the lower crust. Mantle overturns would generate large-scale lateral currents in the upper mantle that would push against Archaean-aged sub-continental lithospheric mantle keels, causing continental drift and orogenesis despite the absence of plate-boundary forces like slab pull. The validity of this is corroborated by the observed displacement of Lakshmi Planum (&gt;1000 Km) on Venus, a planet with no arcs or ridges. Recent models suggest the Abitibi Greenstone Belt formed as an oceanic tract behind a detached ribbon continent during partial breakup of the Southern Superior craton; and represents a possible sample of Archaean oceanic lithosphere. The Abitibi has ∼50 km of apparent stratigraphy composed of 2-10 My mafic-felsic bimodal volcanic cycles that follow assimilation-fractionation trends indicating contamination of mantle-derived basalts with TTG-like anatectites derived from older basalts. ASOL of this type would be difficult to subduct because of its weakness and buoyancy, but would be fertile and could generate large amounts of second-stage melts. There are no sheeted dykes, precluding a seafloor-spreading model, while the absence of basal cumulates or attached mantle means this type of ASOL should not be called an ophiolite. Archaean/Proterozoic unconformities are followed by deposition of Fe-formations, clastic and volcanic rocks that are only rarely affected by sagduction. The increase in siliciclastic input and decreasing sagduction reflect near-global late Archean emergence from the water of stiffening granitic continents due to secular cooling and intra-continental differentiation. Albeit associated with continent-derived siliciclastic debris, many Paleo-Proterozoic volcanic (and plutonic) rocks resemble Archaean ones geochemically. The similarity of magmatic rocks and hot orogenic styles in the Archaean and Paleo-Proterozoic could imply the overall geodynamic regime was similar in both. The Siderian-Rhyacian <jats:italic>Quiet Period</jats:italic> could therefore represent a Stagnant Lid phase that followed the 2.5 Ga Archaean overturn. When the next mantle overturn ruptured the lid at ∼2.2-2.0 Ga (and again at ∼1.9-1.8 Ga), continents would have been set into motion, forming arcs and ridges. Once initiated, arc and ridge segments would have needed to multiply and propagate to create a world-girdling system. Meso-Proterozoic rocks preserve clear evidence of plate mobility, subduction, and orogenesis; but inexplicably, ophiolites, the geological record of seafloor-spreading, are extremely rare prior to 1 Ga. Earth at 2.0 Ga was probably still largely covered by ASOL, possibly similar to the Abitibi, but how and where it was all destroyed and replaced by modern oceanic lithosphere are mysteries. Given the volume of ASOL involved, recognizable by-products of this global-scale reworking process should exist. Voluminous anorthosite-mangerite-charnockite-granite/gabbro suite rocks (AMCG) are mostly of Proterozoic age, requiring either an ephemeral source, or a unique process. Trace element inversion models applied to massif anorthosites imply they crystallized from high-La/Yb melts that do not resemble tholeiitic basalts, invalidating the notion that they are floatation cumulates from basaltic underplates. Model anorthosite-forming melts can, however, be explained by high-pressure melting of an ASOL-like basalt source with garnet-bearing residues. I posit that massif anorthosites record destruction at Proterozoic convergent margins of an ephemeral source: ASOL. When the last ASOL was crushed between converging continents or consumed by an overprinting arc (∼0.8-1 Ga), AMCG rocks ceased to form, and Earth became a modern Plate Tectonic planet. </jats:p>

<jats:p>A belt of Paleocene turbidites with olistostromes, the Abant Formation, crops out for 350 km along the Intra-Pontide Suture in northern Turkey. The Suture constitutes the contact between two major Pontide tectonic units, the Istanbul and Sakarya zones, and the Abant Formation was used as evidence for the Paleocene - early Eocene closure of the Intra-Pontide ocean. We mapped and studied the Abant Formation along the Intra-Pontide Suture. The Abant Formation consists of deformed Paleocene siliciclastic turbidites with mass flows. The blocks in the olistostromes are mainly Late Cretaceous pelagic limestones; there are also Late Jurassic – Early Cretaceous, Late Cretaceous and Paleocene shallow marine limestone blocks. Other rare block types include late Neoproterozoic and Permian granites, basalt, chert and serpentinite. The ophiolitic blocks make up less than 5% of the Abant Formation. Most of the blocks were derived from the south, from the Sakarya Zone; detrital zircon ages from the turbidite sandstones also indicate a predominantly southern source. The Abant Formation was deposited in a foreland basin, which was formed during the Paleocene collision between the Pontides and the Anatolide-Tauride Block. The basin was preferentially located on the Intra-Pontide Suture, because the Suture constituted an old crustal lineament.</jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Ophiolites, melanges and blueschists 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/ophiolites-melanges-and-blueschists">https://www.lyellcollection.org/topic/collections/ophiolites-melanges-and-blueschists</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.7257811">https://doi.org/10.6084/m9.figshare.c.7257811</jats:ext-link> </jats:p>

<jats:p>This study provides a comprehensive analysis combing multi-element (Sr, Y, Th, U, and rare earth elements (REE)) geochemistry and U-Pb geochronology of single-grain apatite, alongside zircon U-Pb ages, from channel sand deposits of the paleo Fen River, collected at the Chaizhuang and Weijiazhuang sites, corresponding to sediments from the Late Pleistocene and late Middle Pleistocene, respectively. The results unveil that the analyzed apatites originated from a varied assemblage of source rocks, encompassing mafic-ultramafic rocks, intermediate to felsic I-type plutons, highly fractionated S-type granites and pegmatites, as well as assorted metamorphic rocks. U-Pb age dating of detrital zircons and apatites identifies three predominant age peaks at 2.4 Ga, 2.2 Ga, and 1.8 Ga, consistent with known tectonothermal episodes within the North China Craton (NCC). The similarity in U-Pb age spectra for both zircon and apatite, along with comparable apatite geochemical characteristics across both the Chaizhuang and Weijiazhuang sections, indicate stable provenance with little to no change from the late Middle Pleistocene to the Late Pleistocene. This continuity in provenance signatures suggest an absence of shift in drainage patterns or sediment sources, indicating that the current location and pattern of Fen River lower reach drainage was not formed at least by then. Consequently, it is inferred that the detrital material composing the paleo Fen River sediments during this period predominantly originated from the NCC.</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.7258187">https://doi.org/10.6084/m9.figshare.c.7258187</jats:ext-link> </jats:p>

<jats:p> Highly differentiated magmas are closely related to the formation of tin deposits. The Lianhuashan Basin and Baiyunzhang Basin, surrounded by multiple coeval tin deposits, developed various types of volcanic and subvolcanic rocks. The diagenetic connections between different types of rocks within the two basins will provide new insight on the silicic magma systems evolution and the impact of highly differentiated magmas on tin mineralization. Both basins have consistent zircon U-Pb ages (143 ∼ 138 Ma) and similar whole-rock Nd isotopes ( <jats:italic>ε</jats:italic> <jats:sub>Nd</jats:sub> ( <jats:italic>t</jats:italic> ) = -5.7 ∼ -3.4) and zircon Hf-O isotopes ranges ( <jats:italic>ε</jats:italic> <jats:sub>Hf</jats:sub> ( <jats:italic>t</jats:italic> ) = -9.0 ∼ -2.5; <jats:italic>δ</jats:italic> <jats:sup>18</jats:sup> O = 5.1 ∼ 7.9), suggesting both basins originate from the same deep-level magma reservoir, followed by different degrees of crystal differentiation and several episodes of crystal-melt separation in their respective shallow-level magma reservoirs. The multiple pulses of magma extraction eventually produced different volcanic rocks, granite porphyry and rhyolite porphyry, while the remaining crystal mush consolidated in situ to form quartz monzonite porphyry. Further studies show that the tectonic regime changed from a compressive to an extensional environment at ∼140 Ma. Consequently, mantle-derived magmas with low oxygen fugacity injected shallow magma reservoirs that able to evolve to a high degree of differentiation through multiple recharge, thus favoring the formation of the Sn deposit. </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.7258282">https://doi.org/10.6084/m9.figshare.c.7258282</jats:ext-link> </jats:p>

<jats:p>The Southeast Tibet has experienced significant deformation during the Late Cenozoic period, characterized by clockwise block rotation and separated by left-lateral strike-slip faults. Through our new field survey, structural analyses and microstructural observations, we have identified an early phase of ductile shear zones along three major faults: the Anninghe, Jinhe-Jinghe fault and Jinpingshan faults. New geochronological and thermochronological data collected from fault zones and carbonatites associated with a tear fault between two right-lateral oblique faults provides evidences that the slip occurred before ∼30 Ma. These new findings have led to a new conceptual model suggests that these NS-trending right-lateral oblique-slip faults, together with these NW-trending left-lateral strike-slip faults in Southeast Tibet, form a network of large conjugate fractures. The network was formed due to N-NE-trending contraction and played a crucial role in controlling the overall tectonic frame of Southeast Tibet during the Oligocene. By compiling and reviewing previous research with our latest findings, we propose that the region has undergone a transtion from oblique dextral to sinistral shearing since the Oligocene, providing new insights into the tectonic evolution of the East Tibet.</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.7262890">https://doi.org/10.6084/m9.figshare.c.7262890</jats:ext-link> </jats:p>

<jats:p> Arc–continent collision is a fundamental stage in the plate-tectonic cycle that allows the continental crust to grow and can influence global climate through chemical weathering. Collision between Australia and the oceanic North Coast Range–New Britain Arc began in the Middle Miocene, resulting in uplift of the modern New Guinea Highlands. The temporal evolution of this collision and its erosional and weathering impacts is reconstructed here using sedimentary archives from the Gulf of Papua. Sr and Nd isotopes show dominant erosion from igneous arc-ophiolite crust, accounting for <jats:italic>c</jats:italic> . 40–70% of the total flux in the Early Miocene, and rising to <jats:italic>c</jats:italic> . 80–90% at 8 Ma, before falling again to 72–83% by the present day. Greater erosion from Australia-derived units accelerated in the Pliocene, like the classic Taiwan collision but with greater erosion from arc rather than continental units. Chemical alteration of the sediment increased through time, especially since <jats:italic>c</jats:italic> . 5 Ma, consistent with increasing kaolinite indicative of more tropical weathering. Erosion was focused in the high topography where mafic arc units are preferentially exposed. Comparison of sediment with bedrock compositions implies that the source terrains have been more efficient at removing CO <jats:sub>2</jats:sub> from the atmosphere compared with Himalayan drainages. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material</jats:bold> : Details of analytical conditions, analytical results and compositions compiled from the GEOROC database 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.7168147">https://doi.org/10.6084/m9.figshare.c.7168147</jats:ext-link> </jats:p>

<jats:p> The Solent Region and Sussex coastal plain in southern England have preserved palaeo-sea-level indicators from multiple interglacial periods, with a particularly complete record of deposition throughout the last interglacial. However, as yet, none of the research on these indicators has fully addressed the relationship of the different types of deposits preserved to mean sea-level. In this paper we apply recent approaches to estimating past relative sea-levels based on applying modern analogues to understand the indicative meaning of these indicators. We also apply a synchronous correlation model previously developed on rapidly uplifting coastlines to assess uplift rates. The uplift rates required to match the elevations of sequences suggest a significant decrease in uplift rates between the Late Wolstonian Substage and Ipswichian Stage; that is, the <jats:italic>c.</jats:italic> 240 and <jats:italic>c.</jats:italic> 125 ka sea-level highstands, broadly equivalent to marine isotope stages (MIS) 7 and 5e. This coincides in time with the final opening of the Straits of Dover. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Fossil data from sites that have not previously been published 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.7172532">https://doi.org/10.6084/m9.figshare.c.7172532</jats:ext-link> </jats:p>

<jats:p> The South China Craton experienced large changes in climate, eustasy and environmental conditions during the Late Ordovician Hirnantian Ice Age, but their impact on the watermass architecture of the Yangtze Sea has not yet been thoroughly evaluated. Here, we reconstruct the salinity–redox structure of the Yangtze Sea based on five Upper Ordovician–Lower Silurian shale successions representing a lateral transect from a deep-water area of the Inner Yangtze Sea (IYS; Shuanghe section) across the shallow Hunan–Hubei Arch (Pengye, Jiaoye and Qiliao sections) to the relatively deep-water Outer Yangtze Sea (OYS; Wangjiawan section). Carbon isotope ( <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>δ</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>13</jats:sup> C <jats:sub>org</jats:sub> ) profiles show that the Guanyinqiao Bed (recording the peak Hirnantian glaciation) thins and is less completely preserved at sites on the flanks of the Hunan–Hubei Arch than in deeper water areas to the SW and NE, reflecting bathymetric influences. Watermass salinities were mainly marine at Shuanghe and brackish at the other four study sites, with little variation among Interval I (pre-glaciation), Interval II (Hirnantian glaciation) and Interval III (post-glaciation). Redox proxies document mainly euxinia at Shuanghe and Wangjiawan and suboxia at the other sites during Interval I, with shifts towards more reducing (mostly euxinic) conditions at most sites during Intervals II and III, which shows that all the study sections were deep enough to remain below the redoxcline during the glacio-eustatic lowstand. Two features of the Shuanghe section mark it as being unusual: it alone exhibits fully marine salinities, implying greater proximity to the open ocean than the other four sites, and it exhibits an especially large shift towards more reducing conditions during Interval III (i.e. the post-Hirnantian transgression), implying greater water depths. These features are difficult to reconcile with the standard palaeogeographical model for the Ordovician–Silurian South China Craton, which is characterized by a geographically enclosed and restricted IYS and a more open OYS, arguing instead for the SW end of the IYS to have been connected to the global ocean and the OYS to have been a restricted oceanic cul-de-sac. A review of sedimentological and facies data for the IYS region suggests that our re-interpretation of the Ordovician–Silurian palaeogeography of the South China Craton is viable, although further vetting of this hypothesis is needed. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> The dataset and the full crossplot of Sr/Ba v. CaO for this study 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.7170648">https://doi.org/10.6084/m9.figshare.c.7170648</jats:ext-link> </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Chemical Evolution of the Mid-Paleozoic Earth System and Biotic Response 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/chemical-evolution-of-the-mid-paleozoic-earth-system">https://www.lyellcollection.org/topic/collections/chemical-evolution-of-the-mid-paleozoic-earth-system</jats:ext-link> </jats:p>

<jats:p> The Andean flank in central Peru is characterized by stepped profiles involving up to 20 surfaces and pediments resulting from multiple episodes of uplift and erosion. The study area exhibits the same sequence of surfaces and pediments. The erosional features are also recognized in the Eastern Cordillera in northern Peru. This paper focuses on the seven highest features in the range <jats:italic>c.</jats:italic> 2800–4700 m. Remnants of the four surfaces higher than 3800 m, which were formed during the interval <jats:italic>c.</jats:italic> 18–12 Ma, are only found south of latitude 6–6.5° S. The Miocene metallogenic belt associated with the Western Cordillera terminates abruptly at that same latitude. The area north of <jats:italic>c.</jats:italic> 6° S does not have any features higher than <jats:italic>c.</jats:italic> 3500 m, which is interpreted as indicating a later initiation of uplift. It also lacks any sign of magmatic activity. On the basis of these factors, the Central Andes are considered to terminate at <jats:italic>c.</jats:italic> 6° S, the ranges to the north being assigned to the Northern Andes. Once episodic uplift was initiated in the area north of 6° S, it continued at the same rhythm as in the region to the south. There was no apparent change in the pattern of episodic uplift when the normal subduction regime changed to a flat-slab regime at <jats:italic>c.</jats:italic> 11 Ma, probably as a result of the subduction of the Inca Plateau. The distribution of the erosion surfaces indicates that episodic uplift affected the whole of the Andean Block in northern Peru. It appears that the individual episodes occurred simultaneously and produced the same amount of uplift over the whole width of the cordilleras. There is no sign of any interruption in the process, implying a continuous orogeny from the Mid-Miocene onwards. </jats:p>