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Elemental fractionation effects during analysis are the most significant impediment to obtaining precise and accurate U‐Pb ages by laser ablation ICPMS. Several methods have been proposed to minimize the degree of downhole fractionation, typically by rastering or limiting acquisition to relatively short intervals of time, but these compromise minimum target size or the temporal resolution of data. Alternatively, other methods have been developed which attempt to correct for the effects of downhole elemental fractionation. A common feature of all these techniques, however, is that they impose an expected model of elemental fractionation behavior; thus, any variance in actual fractionation response between laboratories, mineral types, or matrix types cannot be easily accommodated. Here we investigate an alternate approach that aims to reverse the problem by first observing the elemental fractionation response and then applying an appropriate (and often unique) model to the data. This approach has the versatility to treat data from any laboratory, regardless of the expression of downhole fractionation under any given set of analytical conditions. We demonstrate that the use of more complex models of elemental fractionation such as exponential curves and smoothed cubic splines can efficiently correct complex fractionation trends, allowing detection of spatial heterogeneities, while simultaneously maintaining data quality. We present a data reduction module for use with the Iolite software package that implements this methodology and which may provide the means for simpler interlaboratory comparisons and, perhaps most importantly, enable the rapid reduction of large quantities of data with maximum feedback to the user at each stage.

LA-ICPMS zircon U-Pb dating has been greatly advanced and widely applied in the past decade because it is a cheap and fast technique. The internal error of LA-ICPMS zircon U-Pb dating can be better than 1%, but reproducibility （accuracy） is relatively poor. In order to quantitatively assess the accuracy of this technique, zircons from two dioritic rocks, a Mesozoic dioritic microgranular enclave （FS06） and a Neoproterozoic diorite （WC09-32）, were dated independently in eight laboratories using SIMS and LA-ICPMS. Results of three SIMS analyses on FS06 and WC09-2 are indistinguishable within error and give a best estimate of the crystallization age of 132.2 and 760.5 Ma （reproducibility is -1%, 2RSD）, respectively. Zircon U-Pb ages determined by LA-ICPMS in six laboratories vary from 128.3±1.0 to 135.0±0.9 Ma （2SE） for FS06 and from 742.9±3.1 to 777.8±4.7 Ma （2SE） for WC09-32, suggesting a reproducibility of -4% （2RSD）. Uncertainty produced during LA-ICPMS zircon U-Pb analyses comes from multiple sources, including uncertainty in the isotopic ratio measurements, uncertainty in the fractionation factor calculation using an external standard, uncertainty in the age determination as a result of common lead correction, age uncertainty of the external standards and uncertainty in the data reduction. Result of our study suggests that the uncertainty of LA-ICPMS zircon U-Pb dating is approximately 4% （2RSD）. The uncertainty in age determination must be considered in order to interpret LA-ICPMS zircon U-Pb data rationally.

The Seve Nappe Complex (SNC) comprises continental rocks of Baltica that were subducted and exhumed during the Caledonian orogeny prior to collision with Laurentia. The tectonic history of the central SNC is investigated by applying in-situ zircon and monazite (Th-)U–Pb geochronology and trace element analysis to (ultra-)high pressure (UHP) paragneisses in the Avardo and Marsfjället gneisses. Zircons in the Avardo Gneiss exposed at Sippmikk creek exhibit xenocrystic cores with metamorphic rims. Cores show typical igneous REE profiles and were affected by partial Pb-loss. The rims have flat HREE profiles and are interpreted to have crystallized at 482.5 ± 3.7 Ma during biotite-dehydration melting and peritectic garnet growth. Monazites in the paragneiss are chemically homogeneous and record metamorphism at 420.6 ± 2.0 Ma. In the Marsfjället Gneiss exposed near Kittelfjäll, monazites exhibit complex zoning with cores enveloped by mantles and rims. The cores are interpreted to have crystallized at 481.6 ± 2.1 Ma, possibly during garnet resorption. The mantles and rims provide a dispersion of dates and are interpreted to have formed by melt-driven dissolution-reprecipitation of pre-existing monazites until 463.1 ± 1.8 Ma. Depletion of Y, HREE, and U in the mantles and rims compared to the cores record peritectic garnet and zircon growth. Altogether, the Avardo and Marsfjället gneisses show evidence of late Cambrian/early Ordovician partial melting (possibly in (U)HP conditions), Middle Ordovician (U)HP metamorphism, and late Silurian tectonism. These results indicate that the SNC underwent south-to-north oblique subduction in late Cambrian time, followed by progressive north-to-south exhumation to crustal levels prior to late Silurian continental collision.

Zircon U‐Pb geochronological data on over 900 zircon grains for Cambrian to Silurian sandstone samples from the South China Block constrain the pre‐Devonian tectonic setting of, and the interrelationships between, the constituent Cathaysia and Yangtze blocks. Zircons range in age from 3335 to 465 Ma. Analyses from the Cathaysia sandstone samples yield major age clusters at ∼2560, ∼1850, ∼1000, and 890–760 Ma. Zircons from the eastern and central Yangtze sandstone samples show a similar age distribution with clusters at ∼2550, ∼1860, ∼1100, and ∼860–780 Ma. A minor peak at around 1450 Ma is also observed in the Cathaysia and central Yangtze age spectra, and a peak at ∼490 Ma represents magmatic zircons from Middle Ordovician sandstone in the eastern Yangtze and Cathaysia blocks. The Cambrian and Ordovician strata show a transition from a carbonate‐dominated succession in the central Yangtze Block, to an interstratified carbonate‐siliciclastic succession in the eastern Yangtze Block, to a neritic siliciclastic succession in the Cathaysia Block. Paleocurrent data across this succession consistently indicate directions toward the W‐NNW, from the Cathaysia Block to the Yangtze Block. Our data, together with other geological constraints, suggest that the Cathaysia Block constitutes a fragment on the northern margin of east Gondwana and both Cathaysia and east Gondwana constituted the source for the analyzed early Paleozoic samples. The similar age spectra for the Cambrian to Silurian sandstone samples from the Yangtze and Cathaysia blocks argue against the independent development and spatial separation of these blocks in the early Paleozoic but rather suggest that the sandstone units accumulated in an intracontinental basin that spanned both blocks. Subsequent basin inversion and Kwangsian orogenesis possibly at 400–430 Ma also occurred in an intracontinental setting probably in response to the interaction of the South China Block with the Australian‐Indian margin of east Gondwana.

Quantifying common Pb, the non‐radiogenic Pb present in a mineral independent of in situ U decay, is essential for obtaining accurate U–Pb ages in common Pb‐bearing minerals such as apatite. However, constraining the amount and composition of common Pb, as well as the timing of its entrapment, remains a persistent challenge. Common Pb in apatites may be constrained by assuming a terrestrial Pb model and measuring 204Pb, or by fitting a two‐component mixing line between radiogenic and common components. Here, we utilize an approach that combines in situ K‐feldspar Pb isotopes (a primary common Pb reference due to negligible radiogenic ingrowth) with apatite U–Pb and trace element data. This approach allows us to understand growth relationships between apatite and K‐feldspar, providing a better framework for geo‐thermochronological interpretations. Igneous or high‐grade metamorphic apatite indicates a shared common Pb reservoir with co‐existing K‐feldspar. In contrast, recrystallized, low‐grade metamorphic apatite records distinct common Pb compositions from K‐feldspar in the same rock. Although some ages derived from recrystallized apatite appear statistically significant (e.g., Mean Squared Weighted Deviation ∼1, p(χ2) ≥ 0.05) when anchored in Tera‐Wasserburg plots using K‐feldspar 207Pb/206Pbi, they can be geologically inaccurate as the common Pb composition of recrystallized apatite is demonstrably different to the primary magmatic reservoir recorded by K‐feldspar. Rather, unanchored ordinate intercepts in Tera‐Wasserburg plots may better capture secondary common Pb signatures for recrystallized apatite, constraining common Pb at the time of (re)growth. We highlight the advantages of assessing K‐feldspar‐constrained 207Pb/206Pb corrections using a multi‐proxy geochemical approach, thereby refining thermal histories within complex geological settings.

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

Zircon grains from the metasedimentary lower crust of the Rio Grande Rift, New Mexico, preserve a metamorphic record of the transition from Laramide compression to Eocene extension. Zircon U‐Pb isotopes and trace‐element concentrations from five two‐pyroxene metaigneous granulite xenoliths define discrete populations: older zircon cores (∼15–50 Ma) that are depleted in heavy rare‐earth elements (HREE) but Ti‐rich, and younger zircon rims (∼3–15 Ma) with elevated HREE and lower Ti concentrations. Coupled phase equilibria and garnet‐melt‐zircon trace‐element partitioning calculations show that the older zircon cores equilibrated in thick (>40 km), hot (800–900°C), garnet‐bearing lower crust during the cessation of compression at the end of the Laramide orogeny. Zircon rim domains equilibrated at lower pressures, consistent with >9 km of thinning of the lower crust. Thermal‐kinematic calculations show that these pressure‐temperature‐time constraints require thinning of the lithospheric mantle prior to and during regional Cenozoic extension. Convective erosion of the mantle lithosphere over tens of millions of years, possibly facilitated by dynamics of the Farallon slab, provides a mechanism to facilitate lower crustal heating and extension. Key Points Zircon U‐Pb dates from five granulite xenoliths, Rio Grande Rift, range between ∼50 and ∼3 Ma Zircon cores equilibrated in thick (>40 km), hot (800–900°C), garnet‐bearing lower crust during the Laramide orogeny P‐T‐time constraints require thinning of the lithospheric mantle prior to and during regional Cenozoic extension

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.

The Chuanlinggou Formation in the northern North China preserves the world's earliest multicellular eukaryote microfossils. Here we present a high‐precision zircon U–Pb CA–ID–TIMS age of 1,641.7 ± 1.2 Ma for a tuff layer within the black shales of the Chuanlinggou Formation. The new age is similar to those obtained for black shales from the Cuizhuang Formation in the southern North China, and the Barney Creek and Fraynes formations in the North Australia, indicating synchronous deposition of large volumes of black shales across both the North China and North Australia at ca. 1640 Ma. Global correlations and analysis of the spatial distribution of ca. 1640 Ma black shales and large igneous provinces (LIPs) and associated magmatic rocks in paleogeographic reconstruction reveal a spatiotemporal link between the ca. 1640 Ma LIPs and black shales. The widely distributed ca. 1640 Ma LIPs and black shales in Columbia supercontinent can provide a natural marker for the Statherian/Calymmian boundary at 1,640 Ma. Plain Language Summary Phanerozoic boundaries and the base of the Ediacaran in the international chronostratigraphic time scale are defined by Global Boundary Stratotype Sections and Points (GSSPs). However, the pre‐Ediacaran geological time scale is formally subdivided by approximate absolute ages not tied to any geological units. Our new high‐precision zircon U–Pb CA–ID–TIMS dating of a tuff horizon within black shales of the Chuanlinggou Formation in the North China combined with geochronology on black shales on other crustal blocks reveals synchronous deposition of voluminous black shales at ca. 1640 Ma across the North China, North Australia and other cratons, and a spatiotemporal and possible causal link between the ca. 1640 Ma LIPs and black shales in the Columbia (Nuna) supercontinent. The global‐scale geological event represented by the ca. 1640 Ma LIPs and coeval black shales can provide a natural marker for the Statherian/Calymmian boundary at ca. 1640 Ma in the international chronostratigraphic time scale. Key Points A tuff layer within black shales from the Chuanlinggou Formation has a high‐precision U–Pb CA–ID–TIMS zircon age of 1,641.7 ± 1.2 Ma Deposition of large volumes of black shales occurred synchronously at ca. 1640 Ma across the North China, North Australia and other cratons The global‐scale ca. 1640 Ma LIPs and black shales can provide a natural marker for the Statherian/Calymmian boundary at 1,640 Ma

We present a statistical approach to data mining and quantitatively evaluating detrital age spectra for sedimentary provenance analyses and palaeogeographic reconstructions. Multidimensional scaling coupled with density-based clustering allows the objective identification of provenance end-member populations and sedimentary mixing processes for a composite crust. We compiled 58 601 detrital zircon U–Pb ages from 770 Precambrian to Lower Palaeozoic shelf sedimentary rocks from 160 publications and applied statistical provenance analysis for the Peri-Gondwanan crust north of Africa and the adjacent areas. We have filtered the dataset to reduce the age spectra to the provenance signal, and compared the signal with age patterns of potential source regions. In terms of provenance, our results reveal three distinct areas, namely the Avalonian, West African and East African–Arabian zircon provinces. Except for the Rheic Ocean separating the Avalonian Zircon Province from Gondwana, the statistical analysis provides no evidence for the existence of additional oceanic lithosphere. This implies a vast and contiguous Peri-Gondwanan shelf south of the Rheic Ocean that is supplied by two contrasting super-fan systems, reflected in the zircon provinces of West Africa and East Africa–Arabia.