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The kinematics and deformation pattern along the Altyn Tagh fault (ATF), one of the largest strike‐slip faults on Earth is of great significance for understanding the growth of the Tibetan Plateau. However, the initial rupture along the ATF remains debated given the limited constraints on the depositional age of associated Cenozoic syntectonic strata. Here we investigated the syntectonic Cenozoic strata in the Xorkol Basin, associated with the strike‐slip faulting along the ATF. New uranium‐lead analyses of the carbonate deposits in the Paleogene strata yield dates of 58.9 ± 1.29 Ma, representing the initial rupture of the ATF. This first documented radioisotopic age coincides with the ca. 60 Ma onset timing of India‐Asia collision, highlighting its far‐field effect at the northern edge of the Tibetan Plateau. We infer that the deformation of the entire Tibetan Plateau started synchronously with the India‐Asia collision. Plain Language Summary Carbonate U‐Pb dating techniques applied to rocks associated with the Altyn Tagh fault, a major fault in North Tibet, reveal that the fault started slipping about 58.9 million years ago, coinciding with the time when India collided with Asia. This finding provides new constraints on when and where this fault formed and suggests that the northern Tibetan Plateau started deformation earlier than previously thought. This result emphasizes that the entire Tibetan Plateau deformed simultaneously in the early Cenozoic. Key Points Calcite U‐Pb dating yields ca. 59 Ma age for carbonate strata in the East Xorkol Basin Xorkol Basin was a pull‐apart basin during the Paleocene due to the left‐lateral strike‐slip faulting along the Altyn Tagh fault Widespread Paleocene‐Eocene tectonism in Northern Tibet highlights the far‐field effect of the India‐Asia collision

The Sava Zone of the northern Dinarides is part of the Cenozoic Adria‐Europe plate boundary. Here Late Cretaceous subduction of remnants of Meliata‐Vardar oceanic lithosphere led to the formation of a suture, across which upper plate European‐derived units of Tisza‐Dacia were juxtaposed with Adria‐derived units of the Dinarides. Late Cretaceous siliciclastic sediments, deposited on the Adriatic plate, were incorporated into an accretionary wedge that evolved during the initial stages of continent‐continent collision. Structurally deeper parts of the exposed accretionary wedge underwent amphibolite‐grade metamorphism. Grt‐Pl‐Ms‐Bt thermobarometry and multiphase equilibria indicate temperatures between 550°C and 630°C and pressures between 5 and 7 kbar for this event. Peak metamorphic conditions were reached at around 65 Ma. Relatively slow cooling from peak metamorphic conditions throughout most of the Paleogene was possibly induced by hanging wall erosion in conjunction with southwest directed propagation of thrusting in the Dinarides. Accelerated cooling took place in Miocene times, when the Sava Zone underwent substantial extension that led to the exhumation of the metamorphosed units along a low‐angle detachment. Footwall exhumation started under greenschist facies conditions and was associated with top‐to‐the‐north tectonic transport, indicating exhumation from below European plate units. Extension postdates the emplacement of a 27 Ma old granitoid that underwent solid‐state deformation under greenschist facies conditions. The 40Ar/39Ar sericite and zircon and apatite fission track ages from the footwall allow bracketing this extensional unroofing between 25 and 14 Ma. This extension is hence linked to Miocene rift‐related subsidence in the Pannonian basin, which represents a back‐arc basin formed due to subduction rollback in the Carpathians.

In Western Himalayan Syntaxis, the India‐Asia continental collision occurred at ca. 50 Ma, while its uplift history and exhumation mechanism are still in dispute despite decades of studies. A new type of eclogite was found in Naran, located ca. 30 km southwest of the Upper Kaghan Valley. Phase equilibrium calculations and thermobarometer performed on the Naran eclogite documented the peak‐P metamorphic condition of 720–780°C at 2.4–2.8 GPa. Two further exhumation stages were identified with the first one at high‐P granulite‐facies conditions of 750–800°C at 1.6–1.9 GPa, and the second at amphibolite‐facies conditions of 550–630°C at 0.5–0.8 GPa. SIMS U‐Pb dating of metamorphic zircons yielded an age of 46 ± 2 Ma, which is interpreted to constrain the high‐P metamorphism age along the northwestern margin of the Indian plate. SIMS U‐Pb dating of rutile yielded a cooling age of 26 ± 3 Ma, which is interpreted as cooling age in the amphibolite facies. The average speculated exhumation rate of the Naran massif (∼3 mm a−1) was much lower than that recovered from the Upper Kaghan Valley massif (86–143 mm a−1). The tectonic and metamorphic evolution of the whole Western Himalayan Syntaxis shows the difference in temporal and spatial change within the Paleogene era, indicating the inconsistent exhumation histories of the continental slices. Such a multi‐slice exhumation process was probably related to the closure of the Neo‐Tethys ocean and the break‐off of the Indian lithospheric slab. Key Points Naran eclogite underwent peak metamorphism at ca. 46 Ma with PT conditions of 710–770°C, 2.2–2.8 GPa U‐Pb dating of rutile indicated cooling age of ca. 26 Ma with PT conditions of 580–630°C and 0.6–0.8 GPa Naran eclogite represents a new type of HP rock sequence with a much lower exhumation rate (3 mm a−1) than Kaghan eclogite (30–143 mm mm a−1)

We present new constraints on the age, nature, and tectonic setting of mafic eclogite protoliths from the Maures-Tanneron Massif, southern Variscan belt. Whole-rock major and trace element geochemistry was combined with zircon dating using 206 Pb/ 238 U by LA‒ICP‒MS to improve the understanding of this key-target of the European Southern Variscides. Geochemical data show that protoliths of the mafic eclogites are typical MORBs, while REE and HFSE patterns suggest an E-MORB affinity. However, the geochemical study shows several signs of crustal contamination that increases with the degree of retrogression. A comparison with Sardinian eclogites, which belong to the same Variscan microplate, namely, “MECS” (Maures-Estérel-Corsica-Sardinia), demonstrates that the eclogites are included in migmatites, which is the case for the studied samples, are the most contaminated. The Maures-Tanneron mafic eclogites represent the remnant of an oceanic basaltic crust. Zircon cores display homogeneous Th/U ratios (0.3–0.4), which are consistent with a magmatic origin, and define an age peak at 499.5 ± 2.9 Ma that is interpreted as the most likely emplacement age of the basaltic protolith. This age suggests that this protolith was part of an oceanic floor that was older than the Rheic Ocean and located to the north of the Gondwana active continental margin as predicted by recent unified full plate reconstruction models. Although the studied eclogites are retrogressed, the study of mineral inclusions trapped in garnets combined with thermodynamic modelling yields a P−T range of 17.2–18.5 kbar and 640–660 °C, which is consistent with the standard oceanic subduction palaeo-geotherm. These new data suggest that eclogites recognized in the “MECS” Variscan microplate represent the closure of oceanic domains of different ages (Cambrian or Ordovician). Nous présentons de nouvelles données sur les éclogites mafiques rétromorphosées du massif des Maures-Tanneron (MTM), appartenant à la chaîne varisque méridionale d’Europe. La caractérisation géochimique en éléments majeurs et traces de ces roches a été associée à la datation dans les zircons par la méthode LA-ICP-MS sur U‒Pb, afin d’améliorer la compréhension de cette zone-clé de la chaîne varisque. L’analyse géochimique indique que les protolithes correspondent sans équivoque à des MORBs, les profils en terres rares et HFSE montrant une affinité apparente proche du pôle E-MORB. Il faut cependant envisager les effets d’une contamination crustale, dont l’intensité augmente avec le degré de rétromorphose. La comparaison de nos résultats avec les données obtenues sur les éclogites de Sardaigne, appartenant à la même microplaque varisque Maures-Estérel-Corsica-Sardinia (MECS), indique que les éclogites les plus contaminées, parmi lesquelles les nôtres, se situent toujours dans un encaissant migmatitique. Néanmoins, les éclogites les mieux préservées du MTM proviennent toutes d’un ancien plancher océanique de nature basaltique. La méthode U‒Pb par LA‒ICP‒MS appliquée aux cœurs homogènes des zircons, et dont le ratio Th/U ∼0.3–0.4 est compatible avec une origine magmatique, conduit à un âge de 499.5 ± 2.9 Ma pour les protolithes des éclogites. Cet âge est donc interprété comme l’âge le plus probable du basalte originel. Il témoigne de l’existence d’un espace océanique, qui précède l’ouverture de l’océan Rhéique et se localise à proximité d’une marge active dans le Nord du supercontinent Gondwana. Ce résultat est en accord avec les derniers modèles paléomagnétiques globaux de paléo-cinématique des plaques. Bien que ces éclogites aient subi des modifications importantes au cours de leur rétromorphose, l’étude de la chimie des inclusions minéralogiques « blindées » au sein des cœurs de grenats, combinée à la modélisation thermodynamique sur roche totale, permet de proposer un domaine de conditions P−T maximales de l’ordre de 17,2–18,5 kbar pour 640–660 °C. Ces conditions sont compatibles avec les conditions standard d’un géotherme de subduction océanique. Ces nouvelles données, combinées à celles obtenues en Sardaigne et en Corse, indiquent que les éclogites recensées dans les vestiges de la microplaque MECS témoignent de la fermeture de domaines océaniques d’âges différents (Cambrien ou Ordovicien).

The formation of divergent plate boundaries involves the opening of continental basins and uplift of plate margins accompanied by seawater ingression and the reorganization of surface and groundwater drainage systems. These processes drive water‐rock reactions, resulting in the deposition of epigenetic minerals in the country rock adjacent to the plate boundary. Here, we study the isotopic geochemical record of epigenetic dolomite and ferric‐oxide minerals that occur along tectonic lines in the Negev (southern Israel), which border the Cenozoic rift system that developed between the African and Arabian plates. The observed ranges of new and published O, C, Sr, Mo, Fe, and Pb isotope compositions indicate mixing between the country rock, seawater and deep‐seated groundwater source‐solutions. We suggest that mineralization occurred as brines migrated from their marine source, mixed with groundwater in a deep siliciclastic aquifer environment, and subsequently upwelled along tectonic lines and reacted with the overlying carbonate rocks. Relative and U‐Pb dating of epigenetic minerals suggest that mineralization occurred at 31.4 ± 4.6 Ma in the central Negev sites and at 46 ± 12 Ma and again at 14.5 ± 2.3 Ma in the northeast Negev. The younger two ages overlap the timing of pre‐ Red Sea Rift doming of northeastern Africa and Arabia, driven by the Afar Plume, and lateral‐movement along the Dead Sea Transform (DST), respectively. We associate the youngest mineralization event with a time‐interval in which the DST already hosted a marine lagoon, while the transform's western margin has remained a low relief landscape. Plain Language Summary Stages in the breakup of continental plates are accompanied and recorded by the formation of mineral deposits by water‐rock reactions. We studied dolomite and iron mineralization occurrences along tectonic lines between the Red Sea Rift and its Dead Sea Transform (DST) segments of the Cenozoic rift system between the African and Arabian plates. We combine new and published isotope compositions of O, C, Sr, Mo, Fe, and Pb to identify the sources and timing of mineralization. We demonstrate that the mineralization occurred as seawater migrated through the subsurface, mixed with continental groundwater, and upwelled through tectonic lines to interact with carbonate country rocks. Age constraints based on geological observations and absolute U‐Pb dating suggest three mineralization events at 46 ± 12, 31.4 ± 4.6, and 14.5 ± 2.3 Ma. The two younger events correspond to the timing of pre Red Sea Rift doming of northeastern Africa and Arabia driven by the Afar Plume, and DST. We associate the youngest age with the presence of a lagoon in the DST. The results of this study demonstrate that marine ingression into the DST preceded significant surface uplift of the transform's western margin. Key Points Mineral deposits along the African‐Arabian plate‐margins formed by mixing between country rocks, seawater, and continental groundwater U‐Pb dating indicate three phases of mineralization that overlap intervals of Red Sea Rift and Dead Sea Transform (DST) activities Marine ingression into the DST preceded surface uplift of the transform's western margin

We document the geochemistry of calcite veins in the Late Cretaceous Tikihore Formation (Raukumara Peninsula, New Zealand) to characterize their fluid composition and source and to help establish the age of subduction initiation at the Hikurangi margin of the Australia‐Pacific plate boundary. The calcite veins occur within normal faults offsetting turbidites that accumulated in a lower slope basin. Vein calcite trace metal content and rare earth element patterns are consistent with a seawater‐derived brine composition. Oxygen isotope (δ18O) values range from −6.1 to +8.4‰ and are −0.2‰ VPDB on average; positive δ13C values of up to +28‰ VDPB reflect methanogenesis. Oxygen isotope temperature data indicate that calcite vein mineralization occurred at temperatures in the range of 29°C–48°C. This is markedly less than the maximum burial temperature experienced by the host rocks, which we estimate to be 104 ± 10°C at 30–27 Ma from the inverse modeling of apatite fission track data. The vein calcite has a 28.5 ± 4.9 Ma U‐Pb age. From these data, we infer that the succession above Tikihore Formation was removed by slumping, thereby resulting in fluid overpressure in the reservoir, followed by hydraulic fracturing and the precipitation of the vein calcite. Ultimately, the data presented here from the Tikihore veins are consistent with subduction initiation at 30–27 Ma, based on the U‐Pb age of the vein calcite and modeling of apatite fission track data for the host sandstone, corroborated by the 30–27 Ma timing of back thrusting on the Taranaki Fault and related foredeep development in eastern Taranaki Basin. Plain Language Summary Subduction zones, where, most commonly, an oceanic plate turns down below an overriding continental plate, are among the most dynamic geological settings on Earth. In the frontal part of these zones, known as the forearc region, marine water along with sediments can be transported down the interface of the two plates. One water pathway can be upward into the overriding plate, where it may be trapped in fluid reservoirs. Tectonic processes ultimately fracture these reservoirs, leading to fluids being pumped along these fractures resulting in minerals being precipitated within them. In this study, we analyze the chemistry of a set of calcite veins collected from fracture zones in a sedimentary formation (Tikihore Formation) in the forearc region (Hikurangi margin) of New Zealand. We establish that the fluid source of the veins is indeed marine waters and that they precipitated at relatively cool temperatures (29°C–48°C). Uranium‐lead dating of vein calcite sample material establishes that it was precipitated 28.5 ± 4.9 million years ago. From these data and supporting geological information, we interpret the subduction zone along the Hikurangi margin, which is part of the Australia‐Pacific plate boundary zone through New Zealand, to have started during the interval of 30–27 Ma. Key Points We geochemically characterize calcite veins in normal faults that offset Cretaceous turbidites These veins record hydraulic fracturing and precipitation after rupturing of a reservoir, following exhumation near the new plate boundary The U‐Pb age of the veins together with other results constrains a mid‐Oligocene timing of subduction initiation at the Hikurangi margin

We investigated some of the sampling and mineral separation biases that affect the accuracy of detrital zircon provenance studies. The study has been carried on a natural catchment in the Scottish Highlands that represents a simple two‐component source system and on samples of synthetic sediment prepared for this study to test the effects of heavy mineral separation on the resulting zircon age spectra. The results suggest that zircon fertility of the source rocks and physical properties of zircon represent the most important factors affecting the distribution of zircon age populations in the stream sediments. The sample preparation and selection of zircons for analysis may result in preferential loss of information from small zircon grains. Together with the preference for larger crystals during handpicking, it can result in several‐fold difference compared to the real age distribution in the sediment sample. These factors appear to be more important for the reproducibility of zircon age spectra than is the number of zircon grains analyzed per sample. Key Points Effect of sampling and mineral separation on accuracy of detrital zircon studies Limitations for routine sedimentary provenance analysis based on zircon dating

The large-scale Maoping W–Sn deposit in the Gannan metallogenic belt of the eastern Nanling Range, South China, spatially associated with the Maoping granite pluton, hosts total ore reserves of 103,000 t WO3 and 50,000 t Sn. Two different types of mineralization developed in this deposit: Upper quartz vein-type mineralization, mostly within the Cambrian metamorphosed sandstone and slate, and underneath greisen-type mineralization within the Maoping granite. Cassiterites from both types of mineralization coexist with wolframite. Here we report for the first time in situ U–Pb data on cassiterite and zircon of the Maoping deposit obtained by LA-ICP-MS. Cassiterite from quartz vein and greisen yielded weighted average 206Pb/238U ages of 156.8 ± 1.5 Ma and 156.9 ± 1.4 Ma, respectively, which indicates that the two types of mineralization formed roughly at the same time. In addition, the two mineralization ages are consistent with the emplacement age of the Maoping granite (159.0 ± 1.5 Ma) within error, suggesting a close temporal and genetic link between W–Sn mineralization and granitic magmatism. The two types of mineralization formed at the same magmatic-hydrothermal event. Cassiterite from both types of mineralization shows high Fe, Ta, and Zr contents with a low Zr/Hf ratio, suggesting that the ore-forming fluid should be derived from the highly differentiated Maoping granite pluton. Cassiterite in greisen has higher contents of Nb and Ta but a lower concentration of Ti compared with that in quartz vein, indicating that the formation temperature of greisen-type mineralization is little higher than that of quartz-vein-type mineralization.

In situ U-Pb dating of carbonates is very common in the fields of mining and petroleum geology. However, carbonate minerals generally have low U, high common Pb, multiple generations, and uneven elemental distribution, often resulting in relatively low dating precision. Hence, the success rate in U-Pb dating of carbonates by the traditional spot analysis method is generally low. This paper, through combining a mapping method for U-Pb dating with a proprietary visualization and analysis software, ChronoVA, conducted a comparison of the data obtained by both the spot analysis and the mapping method for 3 carbonate standards and 2 unknown natural geological samples. We successfully developed a U-Pb dating method for carbonate rocks via LA-SF-ICP-MS elemental mapping and discussed the advantages and limitations of this method. Results show that in comparison with the traditional spot analysis method, the mapping approach has the following advantages: (1) reducing the downhole fractionation effect; (2) simplifying the analytical processes; (3) the elemental imaging data can help to identify multi-generation and mineral inclusions, ensuring the obtained carbonate U-Pb age having an interpretable geological meaning; (4) a large amount of mapping data can significantly improve the accuracy of the dating results. Despite these advantages, in carbonate samples with extremely high common Pb content and high Pb/U ratio, it might be difficult to obtain reliable ages even via the mapping method. In addition, it was understood that the carbonate standard WC-1, which is the most commonly used at present, could be inhomogeneous, and on occasion does not satisfy the SK model in spot analysis.

The Khanka Massif is a crustal block located along the eastern margin of the Central Asian Orogenic Belt (CAOB) and bordered to the east by Late Jurassic–Early Cretaceous circum-Pacific accretionary complexes of the Eastern Asian continental margin. It consists of graphite-, sillimanite- and cordierite-bearing gneisses, carbonates and felsic paragneisses, in association with various orthogneisses. Metamorphic zircons from a sillimanite gneiss from the Hutou complex yield a weighted mean 206Pb/238U age of 490 ± 4 Ma, whereas detrital zircons from the same sample give ages from 934–610 Ma. Magmatic zircon cores in two garnet-bearing granite gneiss samples, also collected from the Hutou complex, yield weighted mean 206Pb/238U ages of 522 ± 5 Ma and 515 ± 8 Ma, whereas their metamorphic rims record 206Pb/238U ages of 510–500 Ma. These data indicate that the Hutou complex in the Khanka Massif records early Palaeozoic magmatic and metamorphic events, identical in age to those in the Mashan Complex of the Jiamusi Massif to the west. The older zircon populations in the sillimanite gneiss indicate derivation from Neoproterozoic sources, as do similar rocks in the Jiamusi Massif. These data confirm that the Khanka Massif has a close affinity with other major components of the CAOB to the west of the Dun-Mi Fault. Based on these results and previously published data, the Khanka Massif is therefore confirmed as having formed a single crustal entity with the Jiamusi (and possibly the Bureya) massif since Neoproterozoic time.