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This paper describes the assembly of an updated dataset of detrital zircon geochronology and Lu–Hf isotopes for Turkey, Cyprus and Greek peninsula. This first version of the dataset documented 286 samples with detrital zircon U–Pb data and 70 samples with zircon Lu–Hf isotopes from 42 published articles. These samples are mainly distributed in seven geologic‐tectonic units in the Eastern Mediterranean Tethyan region. The compilation of dataset will be periodically accessed in the Deep‐Time Digital Earth repository, containing more updated raw data of (un)published scientific research. We believe that the construction of such a dataset is fundamental to studies of clastic strata and also to understanding of crustal evolution in the Eastern Mediterranean region. [ABSTRACT FROM AUTHOR]

Understanding the composition, formation and evolution of the oldest continental crust is crucial for comprehending the mechanism and timing of crustal growth and differentiation on early Earth. However, the preservation of the ancient continental crust is limited due to extensive reworking by later tectonothermal events. In the Lulong area of eastern Hebei, abundant ca. 3.8–3.4 Ga detrital zircons of the fuchsite quartzite have been previously identified. Nonetheless, the provenance and Hf isotopic compositions of the fuchsite quartzite remain unclear. In this study, we present new detrital zircon ages and Hf isotopic for the fuchsite quartzite in the Lulong area to establish the timing of deposition, the provenance and the regional stratigraphic relationship. Zircon U-Pb dating indicates that the fuchsite quartzite was deposited between 3.3–3.1 Ga and most grains were sourced from the 3.8 Ga TTG gneisses and Paleoarchean magmas. Field investigations and regional correlations reveal that the fuchsite quartzite from the Lulong area is equivalent to that of the Caozhuang area. Zircon Hf isotopic data from eastern Hebei Province (Lulong and Caozhuang areas) and Anshan and Xinyang areas indicate that the oldest crustal growth event of North China Craton occurred in the Hadean. [ABSTRACT FROM AUTHOR]

The Xinghongpu Formation is very important for understanding the Devonian tectonic evolution of the South Qinling orogenic belt. Geochemical, detrital zircon U-Pb-Hf isotopic studies were carried out on the Late Devonian metasedimentary rocks of the Xinghongpu Formation to constrain the depositional age, the provenance, and the tectonic setting. The detrital zircon U-Pb dating results revealed that the depositional age of the Xinghongpu Formation of the Late Devonian was not earlier than 363.2 Ma. The whole-rock geochemistry suggested that (1) this suite of metasedimentary rocks was mainly derived from quartzose sediments of mature continental provenance, with a small contribution from mafic and intermediate igneous provenance, and (2) the metasedimentary sandstone of the Xinghongpu Formation from the Late Devonian was deposited in an active continental margin to continental arc setting. The detailed detrital zircon U-Pb dating showed that the age spectra of detrital zircon could be divided into four groups: (1) 416–480 Ma, accounting for about 23%; (2) 740–850 Ma, accounting for about 19%; (3) 889–1017 Ma, accounting for about 19%; and (4) 1072–1146 Ma, accounting for about 12%. It also contained a group of Early Proterozoic zircons. The age and Hf isotope of the detrital zircons suggested that the clastic sediment deposited in the Xinghongpu Formation mainly came from the South Qinling Orogenic Belt and the North Qinling Orogenic Belt. The detrital zircon Lu-Hf isotopes indicated that most zircons were the products of the ancient crustal remelting, and the mantle-derived magmatic sources contributed to the provenance. The Xinghongpu Fm. formed in an oceanic basin in a continental margin environment with arc systems. [ABSTRACT FROM AUTHOR]

The Jiao-Liao-Ji belt (JLJB), in the Eastern Block of the North China Craton, is a major Paleoproterozoic orogen and underwent a complicated tectonic evolution during 2.2–1.8 Ga. The Liaohe Group, an important stratigraphic unit in the JLJB, is key to understanding the complex evolution of this belt. In this paper, we present new detrital zircon U–Pb ages and Hf isotope data for meta-sedimentary rocks from the Gaixian Formation in different areas of the JLJB, in addition to compiled data for other formations of the Liaohe Group, to establish the depositional age and source of detrital materials of the group. U–Pb age results show that the age ranges of zircons from the different samples are broadly similar. The youngest zircon group is ca. 2.06 Ga, and the youngest single-grain age is ca. 2.0 Ga, constraining the depositional age of the Gaixian Formation to between 2.0 Ga and the metamorphic age of ca. 1.9 Ga. The zircon age data indicate that the provenance was primarily Archaean basement of the Nangrim Block and Paleoproterozoic volcanic rocks of the Li'eryu Formation. On the basis of the new geochronological data and results from previous studies, it is inferred that the JLJB underwent a successive process of rifting–subduction–collision, with the different formations of the Liaohe Group being deposited in different stages from rift to passive continental margin and then to active continental margin. Zircon Hf isotope data from the JLJB and adjoining Longgang and Nangrim blocks indicate that a major crustal growth event occurred at 2.9–2.5 Ga, followed by crustal growth and intense recycling of ancient crust at ca. 2.2 Ga. [ABSTRACT FROM AUTHOR]

The Mongol–Okhotsk fold belt is one of the major structural elements of East Asia. In this article, we present U–Pb age and Hf isotope data for detrital zircons from metasedimentary rocks of the Galam Terrane. Our new data confirm that these rocks contain a significant amount of Archean and Paleoproterozoic zircons: most grains, regardless of age, have negative εHf(t) values from –30.0 to –10.0 and model age tHf(C) > 2.2 Ga. The main sources of detrital material for the metasedimentary rocks of the Galam Terrane were igneous and metamorphic complexes of the southeastern margin of the Siberian Craton. Some of the Devonian and Carboniferous zircons have slightly negative and positive εHf(t) values of ‒7.4 to +6.9 and younger tHf(C) ages of 1.46–0.90 Ga. These zircons were derived from eroded island arcs in the Mongol–Okhotsk Paleocean. Our results suggest that the Galam Terrane is a Paleozoic accretionary complex of the Siberian Craton. [ABSTRACT FROM AUTHOR]

It is unclear whether the South China blocks have an affinity with continental Gondwana due to a lack of direct Pan‐African magmatic and metamorphic features. In this study, we conducted U‐Pb geochronological and Lu‐Hf isotopic analyses for detrital zircons from a sandstone of the Chang'an Formation of the Nanhua Group in the Longsheng region of northern Guangxi, with the aim of constraining the timing of sedimentation and information as to its source, as well as seeking evidence for Pan‐African events in the South China blocks. The results show that the ages of detrital zircons peaked at 654.7 ± 6.2 Ma, 773.2 ± 4.1 Ma and 821.9 ± 6.5 Ma, with some at 920–870 Ma; the youngest age indicates the existence of the Pan‐African thermal event. The ∊Hf(t) and TDM2 values demonstrate that the study area has experienced three stages of crustal growth at 3.0–2.4 Ga, 2.1–1.5 Ga and 1.3–0.9 Ga. With intensively distributed Neoproterozoic mafic‐ultramafic and granitic plutons emplaced at 830–810 Ma along the southwestern section of the Jiangnan Orogenic Belt and positive ∊Hf(t) values from a large group of zircon grains, it is proposed that the sediments of the Chang'an Formation (of Nanhua Group) were largely sourced from the southeastern margin of the Yangtze block. Comparison with the zircon age spectra of the Cathaysian block shows that about 79% of the Pan‐African aged detrital zircon grains that have TDM2 = 1352–1031 Ma and ∊Hf(t) = 3.68–8.79, were sourced from the recycled Grenvillian crust of the Cathaysian block, suggesting that the Cathaysian block had a close connection with Gondwana. [ABSTRACT FROM AUTHOR]

The Proterozoic evolution of Laurentia involved intermittent orogens and arc-related crustal growth along a modern-style convergent margin, termed the Great Proterozoic Accretionary Orogen (GPAO). The major lithotectonic provinces of the GPAO in the United States are exposed as telescoped equivalents within the thrust stack of the Grenville Province in Canada. We report zircon U Pb and Lu Hf isotope analyses for two orthogneisses and one quartzite from Archean and Paleoproterozoic domains in the gneiss belt of the SW Grenville Province, Canada. The data constrains Paleoproterozoic crustal growth and sedimentation for this part of the Laurentian margin. The orthogneisses have similar zircon U Pb and Lu Hf isotope systematics that reflect igneous reworking (ca. 1700–1660 Ma) of a Penokean aged (ca. 1.9 Ga) depleted mantle derived source, along with metamorphic reactivation at both ca. 1.45 Ga and during the Grenville Orogeny (1.2–1.0 Ga). The quartzite has a bimodal Paleoproterozoic (2.1–1.8 Ga) and Archean (> 2.5 Ga) detrital zircon age spectrum. The Paleoproterozoic detrital zircon grains have a wide range of Hf(t) compositions (εHf(t) = −12.5 to 10) reflecting co-eval interaction of Archean and depleted Paleoproterozoic sources, contrasted by a more restricted range for the Archean population (εHf(t) = −7 to 4). The new data support the presence of reworked ca. 1.9 Ga depleted mantle sources in the Paleoproterozoic Parautochthon, which extend further east than previously thought. They also identify correlations amongst detrital zircon age spectra and Hf isotope compositions in quartzites from different locations of the Archean Parautochthon. • Juvenile Penokean sources (∼1.9 Ga) extend into the SW Grenville Province. • Penokean (∼1.9 Ga) crust-mantle mixing recorded by detrital zircon Lu Hf isotopes. • Erosion and redeposition of sedimentary sinks can mask orogen detrital systematics. [ABSTRACT FROM AUTHOR]

• Coeval sanukitoids and TTGs at ca. 2540 Ma from the Aravalli orogen, NW India. • Long-lived continental arc magmatism at 1875–1810 Ma: reworking of older crust. • Single-stage formation of sanukitoids: interaction of enriched mantle wedge by TTG melts. • Metasedimentary cover rocks deposited at < 1730 Ma in a post-rift passive margin. The central Aravalli-Banded Gneissic Complex in NW India is an Archean nucleus that was extensively reworked during the late Paleo- to Neoproterozoic. New results of combined zircon U-Pb-Hf isotopes and whole-rock geochemical data reveal that the basement was affected by felsic magmatism during the Neoarchean and Paleoproterozoic, followed by a passive margin stage. The results provide evidence for coeval emplacement of sanukitoids and TTGs at ca. 2540 Ma, and for granitoid magmatism at ca. 1875 Ma. Similar REE patterns of the synchronous sanukitoids and TTGs, coupled with high SiO 2 contents (59.2–70.9 wt%), subchondritic εHf 2.55 Ga values (−5.0 to −2.6) and Hf-model ages (3246–3123 Ma) of the Masuda sanukitoids indicate that the sanukitoid magmas were formed mainly by interaction of TTG magmas (generated by the melting of subducted Paleo- to Mesoarchean oceanic crust) with the overlying enriched peridotite. The calc-alkalic and magnesian compositions, enrichment in LREE and LILE along with pronounced depletion in HFSE (Nb, P and Ti) in ca. 1875 Ma granitoid gneisses imply subduction-related magmatism during Paleoproterozoic. The predominance of subchondritic εHf 1.87 Ga values, ranging from −4.4 to +1.7, suggests that the parental magmas mainly resulted from the reworking of heterogeneous Meso- to Neoarchean felsic crust. Age-Hf isotope data of detrital zircon grains provide evidence that clastic sedimentary rocks covering the central Aravalli basement were deposited in a passive margin setting at < 1730 Ma, and the detritus was mainly sourced from adjoining Neoarchean and Paleoproterozoic granitoids. Comparison of our new data with other Indian and worldwide cratons indicate that the Aravalli orogen represents a unique terrane, where the Neoarchean TTGs and sanukitoids with subchondritic Hf isotopic signatures were emplaced nearly coeval in a close spatial relationship. The Aravalli Archean basement was subsequently reconfigured by voluminous felsic magmatism during Paleoproterozoic at 1875–1810 Ma. Furthermore, the compiled zircon U-Pb age and Hf-Nd isotope data for the late Paleoproterozoic subduction-related magmatic rocks provide evidence for substantial crustal reworking during assembly of the Columbia supercontinent. [ABSTRACT FROM AUTHOR]

The temporal–spatial framework of arc amalgamation is an important key for understanding the anatomy of orogenic collages, present and past. The Junggar‐Balkhash Ocean was a major branch of the southern Paleo‐Asian Ocean where several arcs were amalgamated. Among them, the Dananhu arc with its characteristic juvenile magmatism and lack of Precambrian basement is an efficient recorder of the evolutional history. From our U–Pb and Lu–Hf isotopic analyses of Devonian to Triassic sediments in the Dananhu arc and Permian sediments in the Yamansu‐Central Tianshan arc, we discovered two major changes in detrital zircon provenance of the Dananhu arc: (a) An increasing input of Precambrian ages from the Mongolia collage at 850, 1,850, and 2,500 Ma, together with Phanerozoic zircons ranging from 420 to 480 Ma with negative εHf(t) value since ca. 288 Ma; (b) the presence of the Yamansu‐Central Tianshan arclike Precambrian age cluster of 1,400–1,600 Ma around 243 Ma. In combination with regional tectonothermal events, these two changes correspond to the formation of the Harlik‐Dananhu composite arc in the latest Carboniferous–early Permian followed by its collision with the Yamansu‐Central Tianshan arc in the latest Permian–early Triassic, which marks the termination of the eastern Junggar‐Balkash Ocean. Analysis of the sedimentary successions within the intraoceanic arcs sheds light on the amalgamation history of the Central Asian Orogenic Belt. [ABSTRACT FROM AUTHOR]

The depositional ages of two Proterozoic supracrustal belts, the older Aravalli Supergroup and the younger Delhi Supergroup, overlying the Aravalli Banded Gneissic Complex in NW India are still unresolved. This study presents new combined detrital zircon U–Pb and Lu–Hf isotope data of two quartzite successions from the Alwar complex of North Delhi Supergroup to constrain the depositional ages and Precambrian crustal evolution. The new results show about 90% of detrital zircon population at ca. 1850 Ma, with minor age peaks at ca. 2900, 2700, 2500 and 2200 Ma and older Eo- to Paleoarchean zircon grains at 3655 ± 20 and 3222 ± 27 Ma. The age peaks of 1850 and 2500 Ma correspond to the known magmatic events, while the detritus for others were derived from a so-far unknown crustal source(s) in the region. The data also suggest two metamorphic overprints at 1470–1420 Ma and ca. 1650 Ma, which are consistent with known events of metamorphism in the region. The zircon U–Pb ages, Hf isotopes and field relations indicate that the sedimentary protoliths of the studied quartzite were deposited at ca. 1750 Ma in a collisional setting after the emplacement of subduction-related ca. 1850 Ma granitoids, but prior to the intrusion of 1730–1700 Ma rift-related A-type granites. The regional correlations suggest that the quartzite successions are not part of the Alwar Group as currently considered, but that they apparently belong to the older Aravalli Supergroup. Largely subchondritic εHf values for most of the zircon population signify predominance of crustal reworking during Neoarchean and Paleoproterozoic. The Hf model ages of the Eoarchean zircon indicate the existence of an ancient crust at ca. 4000 Ma in the Aravalli orogen and/or its hinterland. [ABSTRACT FROM AUTHOR]

[Display omitted] • New Sr-Nd-Pb isotopes and detrital zircon U-Pb ages of samples from the Paleoproterozoic to Lower Permian Daoshitou Formation (P 1 d) in Central Yunnan are reported. • The Li-rich claystone of the Daoshitou Formation (P 1 d) are mainly derived from the underlying Weining Formation (C 2 w) basement. • Detrital zircon crystals of the Daoshitou Formation (P 1 d) primary sourced from the Early Ordovician strata. A new lithium-rich claystone from the Lower Permian has been detected in Central Yunnan, Southwestern China that could be great potential for Lithium (Li) exploration, yet the origin of the claystone is still being debated. To study it further, new geochronological, geochemical, and Sr–Nd–Pb isotopic analyses were systematically conducted on the Daoshitou Formation (P 1 d) claystone, as well as on the underlying strata. Through detrital zircon U–Pb dating of the claystone in the Daoshitou Formation, three major age peaks were revealed, at ∼960 Ma, ∼790 Ma, ∼550 Ma, respectively, along with three minor peaks of ∼2500 Ma, ∼1500 Ma, and ∼1200 Ma. Detrital zircons in the claystone have age spectra that closely match those of the Lower Ordovician sedimentary rocks in Central Yunnan, indicating these rocks are the major contributor of detrital zircons. However, the rock source determined by geochemical features decouples with the zircon source determined by detrital zircon data. The A–CN–K ternary diagram obviously reveals analogous predicted weathering trends between the Weining Formation (C 2 w) and Daoshitou Formation, suggesting a potential provenance link. Furthermore, the weathering trends of samples from three drill cores indicate that the transformation of clay mineral (smectite–illite–chlorite/kaolinite) may facilitate Li enrichment. Smectite, as the precursor mineral for Li enrichment, typically forms and preserves in a slightly alkaline environment, which suggests that the Li-rich claystone is likely to formed in this environment. Low Na/Li and K/Li ratios indicate low cation exchange selectivity in sedimentary environments, which promote the proliferation of adsorption sites for Li on smectite. The weathering products from the Weining Formation, composed of impure carbonates, could provide a slightly alkaline environment with low ion strength for the adsorption of Li. In addition, Sr–Nd–Pb isotopic compositions also reveal the significant similarity between the Daoshitou Formation and Weining Formation. Therefore, we suggest that the weathering of the Weining Formation provided the primary material to Daoshitou Formation claystone. [ABSTRACT FROM AUTHOR]

[Display omitted] • The sandstones overlying the OB were deposited after 1.7 Ga. • The OB is an ancient block with some Paleoarchean crust materials. • Predominant crust growth in the OB occurred at early Neoarchean. • 2.5–2.4 Ga, 2.2–2.0 Ga, and 1.95–1.8 Ga events were recorded in the OB. The Ordos Block (OB) is generally considered to be an important micro-block concerning the early geological evolution of the North China Craton (NCC). Previous geophysical and limited geological researches for the OB basement have provided a preliminary understanding of the lithological assemblages and geological structure of the basement, but little was discussed about its formation time and early Precambrian evolution. In this contribution, to better understand the formation and evolution of the OB basement, the new LA-ICP-MS U-Pb ages, Lu-Hf isotope, and trace element composition have been carried for the detrital zircons from the sandstones of the Changcheng System overlying the OB basement. The youngest concordant U-Pb age constrains the Changcheng System to be deposited after ∼1.7 Ga, consistent with the Changcheng System in the other regions of the NCC. The 3.6–3.3 Ga detrital zircons preserved in the sandstones from the Changcheng System, associated with the 3.4 Ga inherited zircon in basement rocks, indicate the potential presence of Paleoarchean crustal materials in the OB. The 2.8–2.6 Ga zircons with positive ε Hf (t) values (+0.6 to +6.4) have the two-stage model ages (T DM C = 3.23–2.75 Ga) close to their formation ages, combined with the crustal thickening during this period, suggesting a major crustal growth in the early Neoarchean. In addition, the main age clusters of the 2.5–2.4 Ga, 2.2–2.0 Ga, and 1.95–1.8 Ga yield ε Hf (t) values of −6.9 to +7.7 with T DM C of 3.39–2.47 Ga, −13.4 to +7.5 with T DM C of 3.49–2.19 Ga, and −14.0 to +2.2 with T DM C of 3.41–2.40 Ga, respectively, indicative of three main stages of crustal reworking associated with two stage of minor juvenile crustal growth around 2.5–2.4 Ga and 2.2–2.0 Ga. They were corresponding to partial melting of the continental crust in the late Neoarchean, magmatism resulting from the plate subduction in the mid-Paleoproterozoic, and the collision and amalgamation between eastern and western blocks in the late Paleoproterozoic, respectively. All demonstrate that the OB was an ancient block formed mainly in the early Neoarchean and then subjected to three strong tectonothermal events of 2.5–2.4 Ga, 2.2–2.0 Ga, and 1.95–1.8 Ga, which occurred in the peripheral orogenic belts. [ABSTRACT FROM AUTHOR]

The Holocene sedimentary evolution in the northern South China Sea has significant implications for sedimentary records resulting from combinations of climate change, sea level rise, and changes in surface circulation. U-Pb geochronology and Lu-Hf isotopes of detrital zircons from the Holocene sediments at the head of the Shenhu submarine canyons, integrated with onshore geochronological data reveal variations in provenance related to these factors. The detrital zircons exhibit a wide range of U-Pb ages from 3829.7 to 41.5 Ma characterized by peak ages centered on 140–154 Ma, 240–258 Ma, 425–452 Ma and 738–991 Ma. Zircon Hf isotopic compositions show a broad range of 176Hf/177Hf ratios from 0.2800714 to 0.282924, with ε Hf (t) values ranging from −27.8 to +14.3. Our results suggest that the Holocene sediments were primarily derived from the Pearl River system and the drainage systems in Taiwan, and the sources in Hainan and Luzon are not represented in these sediments. A rapid shift from Pearl River-dominated to Taiwan-dominated provenance occurred between 4.91 and 4.45 ka BP, which is interpreted to be caused by sea level rise and variations in the surface circulation in the northern South China Sea during the Holocene. Our study also reveals that the reworking of ancient continental crust dominated the evolution of the South China Craton, including tectonic-magmatic events at ca. 2491 Ma, 1843 Ma, 968 Ma, 810 Ma, 440 Ma, 251 Ma and 147 Ma. In contrast, Neoproterozoic accretion of the Cathaysia and Yangtze blocks was accompanied by juvenile additions to crustal growth. • Detrital zircon revealed a variable provenance in the Shenhu submarine canyons • Quantitative analysis indicated Pearl River and Taiwan were the major sources • Shift in provenance was related to the sea level rise and surface circulation • Reworking of ancient crust dominated the South China Craton since Archean [ABSTRACT FROM AUTHOR]

Sandstones and mudstones collected from the Cambrian sedimentary sequences in the Zhuguangshan area were analyzed to trace their provenance, weathering conditions, depositional environment, and Precambrian tectonic evolution in the Cathaysia Block, South China. Detrital zircon geochronology defines at least five populations: 2658–2370 Ma, 1866–1500 Ma, 1390–1268 Ma, 1250–858 Ma, and 830–700 Ma. The 2648–2370 Ma population may correspond to the Neoarchean global continental growth. The 1816–1510 Ma population may represent a subduction event caused by the assembly of the Columbia supercontinent. The 1390–1268 Ma and 1250–858 Ma population reflect the tectono-thermal events associated with the assembly of the Rodinia supercontinent, while the 830–700 Ma population may be associated with the breakup of the Rodinia supercontinent. Detrital zircon Hf isotopic compositions indicate that the mechanism involves multiple juvenile inputs and the reworking of older crustal materials. The sandstones and mudstones display K 2 O enrichment, but they are moderately to extremely depleted in Na 2 O, CaO and Sr. The major and trace elements reveal that the sandstones and mudstones were derived from recycled felsic rocks and deposited in the passive continental margin. The compositions of the protoliths are inferred equivalent to andesite to granodiorite. The petrographic and geochemical features indicate that the sandstones and mudstones have undergone medium to intensive chemical weathering. Conversion of aluminous clay minerals to illite is inferred to be the predominant post-depositional potash metasomatism. [ABSTRACT FROM AUTHOR]

The present work aims to contribute to the Cenozoic tectonic setting of the western part of the Makran Accretionary Wedge in SE Iran. We determine the provenance of both deep marine turbiditic and deltaic-shelf Late Cretaceous-Miocene sandstones, describe the sandstone modal framework and heavy minerals and report a new geochronological and isotopic study including 2307 detrital zircons U-Pb ages and 204 in-situ Hf isotopic analyses. Modal sandstone framework compositions indicate that a magmatic arc and recycled accreted sediments were the main sources of Eocene-Oligocene and Miocene sandstones. Cr-spinel and heavy mineral assemblages indicate ultramafic rocks, likely ophiolitic mantle, as a subsidiary source. Detrital zircon U-Pb ages cluster in five main age groups: (1) Neoproterozoic grains suggesting a continental crust provenance within the Central Iran blocks, (2) Jurassic grains with Hf isotopic compositions of continental crust, suggesting a rifting related magmatic provenance, (3) Late Cretaceous and (4) Eocene grains, with Hf isotopic compositions typical of continental crust and non-depleted mantle, suggesting a continental magmatic arc provenance, and (5) Early Miocene grains. The new U-Pb age and Hf isotopic ratios correspond to those obtained in the east Iranian Makran. They fit tectonic reconstructions with Middle Jurassic intracontinental rift, Early Cretaceous to Eocene subduction below Central Iran forming a continental arc to the north of Makran and closure of the related oceanic in the Paleogene. Erosional products of the corresponding magmatic arc are found in the Makran Basin. Our data disprove that provenance characteristics of the Makran sedimentary rocks are consistent with derivation from the Himalayan sources. [ABSTRACT FROM AUTHOR]

• Constrain the source and depositional age of the Ediacaran turbidites in the Skoura inlier. • Late Neoproterozoic crustal evolution recorded in the Moroccan Anti-Atlas and High Atlas-Meseta. • Geodynamic model of the north-western Gondwana margin during the Ediacaran. A thick succession of marine turbidites from the Skoura inlier (Central High Atlas) are studied here for the first time, using zircon LA-ICP-MS U-Pb dating, trace elements and Hf isotope geochemistry, to constrain the crustal evolution of the northwestern Gondwana margin, close to the West African Craton, during the late Neoproterozoic time. Zircon grains were extracted from four samples of lower Ediacaran siliciclastic rocks from the Skoura inlier (Central High Atlas, Morocco) in order to characterize the maximum depositional age and the provenance of the turbidites, as well as to analyse the composition of the magmatic sources where the zircon grains were formed. The maximum depositional ages of the four samples define a range of ca. 652–612 Ma (652.1 ± 5.7 Ma in sample KS, 621.2 ± 14.0 Ma in sample TA, 619.3 ± 10.0 Ma in sample AG and 611.7 ± 8.2 Ma in sample AS). The age distribution of detrital zircon grains suggests the existence of several sources comprising several populations dated at ca. 3200–2500 Ma, 2300–1800 Ma, 1600–1000 Ma, 950–650 Ma and 630–610 Ma. The detrital zircon grains show notable Mesoproterozoic ages and abundant peaks in the range of ca. 2200–2500 Ma that are considered absent in the West African Craton, implying contribution of other sources. Zircon REE patterns display prominent positive Ce anomalies, negative Eu anomalies and HREE enrichment, which are typical characteristics of a magmatic source as indicated by their high Th/U ratios and oscillatory zoning. The εHf (t) varies from + 0.6 to + 17.0 with a notable cluster between + 5 and + 15 for the Neoproterozoic zircon grains (ca. 720–611 Ma), indicating juvenile sources with slight mixing of old crust. The pre-Neoproterozoic populations indicate that juvenile sources and reworking of old crust played a role in the continental growth of the north-western margin of the West African Craton. The Skoura turbidites were deposited at ca. 650–610 Ma synchronous with orogenic processes in the northern West African Craton margin during the assembly of Gondwana. [ABSTRACT FROM AUTHOR]

• Conglomerate succession in the Udaipur area was deposited at < 1735 Ma. • Deposition took place in an extensional basin, accompanied by A-type magmatism. • Depositional ages are contemporaneous with sedimentation in the North Delhi basin. • Minor reworking of the late-Hadean/Eoarchean crust during the Paleoarchean. • Substantial reworking of Paleo-Neoarchean crust during the Neoarchean- Paleoproterozoic. The inconsistent stratigraphic framework of the Proterozoic successions in the Aravalli orogen, NW India hinders the detailed reconstruction of its geodynamic evolution during the Archean to Paleoproterozoic. In this study, we present new results of combined U-Pb-Hf isotope data of detrital zircon grains of two conglomerate samples from the southern Aravalli orogen, presently assigned to the upper unit of the Aravalli Supergroup. The youngest concordant zircon grains in both the conglomerates yield concordia ages of 1735 ± 13 Ma (n = 2) and 1736 ± 15 Ma (n = 2), respectively, interpreted as maximum ages of deposition. Older zircon grains mostly reveal Neoarchean to Paleoproterozoic age clusters at 2560–2550, 1870–1860 and 1760–1740 Ma, and minor Paleoarchean ages between 3558 ± 17 Ma and 3239 ± 14 Ma, corresponding to known magmatic events in the Aravalli orogen. Most detrital zircon grains show subchondritic εHf t values (+6 to −20), signifying minor reworking of late Hadean/Eoarchean crust during the Paleoarchean, and substantial reworking of Paleo-to Neoarchean crust during the late Neoarchean and Paleoproterozoic, with only minor juvenile input. The maximum depositional ages indicate that the investigated conglomerates were deposited either synchronous or after the emplacement of extension-related A-type granites, which intruded the Aravalli orogen between 1733 ± 9 Ma and 1703 ± 5 Ma. Furthermore, the data suggest that the conglomerates do not belong to the upper Aravalli unit as envisaged by previously published stratigraphic concepts. Instead, these were deposited earlier, during opening of a rift-related basin, grading from a terrestrial into a marine environment, contemporaneous with other sedimentary successions exposed in the North Delhi basin, which are presently assigned to the North Delhi Supergroup. The compiled zircon age-Hf isotope data additionally provide evidence for a series of late Hadean to Archean juvenile crust formation events in hinterland of the Aravalli orogen at 4200–3300 Ma for east Indian cratonic blocks and 3550–3100 Ma for northern and southern cratonic nuclei, and 2700–2500 Ma all over India. Substantial crustal reworking took place during the late Neoarchean at 2500 Ma, and the late Paleoproterozoic at 1850 Ma and 1730–1700 Ma. [ABSTRACT FROM AUTHOR]

• Detrital zircon age and Hf isotope and whole-rock Nd isotope data are provided for Mesoarchean, Paleoproterozoic, Neoproterozoic, and Paleozoic glacial diamictites from around the world. • Hf and Nd isotope data record major episodes of crustal growth at 3.2, 2.8–2.7, 2.0–1.7, and 1.3–0.9 Ga, • Zircons older than 3.6 Ga are completely absent, as is Hf and Nd isotope evidence for reworking of greater than 3.6 Ga continental crust; such crust appears to have been rare. Diamictites produced by continental glaciations were deposited in the Mesoarchean (∼2.9 Ga), Paleoproterozoic (∼2.4–2.2 Ga), Neoproterozoic (∼0.75–0.58 Ga), and Paleozoic (∼0.3 Ga), and, with the exception of the Mesoarchean, occur on multiple modern continents. We examine the provenance of a selection of these diamictites from all four time periods and three continents via detrital zircon U-Pb geochronology and Hf isotope and whole-rock Nd isotope analyses. Mesoarchean samples from South Africa contain mostly Mesoarchean zircon, with a much smaller number of Paleoarchean grains. Zircon Hf and whole-rock Nd point towards their derivation from reworked Paleoarchean crust. Paleoproterozoic samples from North America share a similar unimodal zircon age distribution, with a peak at 2.7 Ga and a narrow range in Hf isotopes that is slightly superchondritic. Coupled with whole-rock Nd results, these data point to their derivation from reworked juvenile Mesoarchean crust. By contrast, the Nd isotope data and existing published detrital zircon U-Pb data for Paleoproterozoic diamictites from South Africa indicate a mix of Neoarchean and Mesoarchean sources. Neoproterozoic samples from Namibia share a Paleoproterozoic detrital zircon population with variable but subchondritic Hf isotope compositions, indicating derivation from reworked Neoarchean crust. Most samples also have Mesoproterozoic and Neoproterozoic zircon with both positive and negative ε Hf(i) , and all have Nd isotope compositions yielding Paleoproterozoic model ages. A Neoproterozoic sample from Canada contains mostly Neoproterozoic detrital zircon with variable Hf isotope compositions, indicating a mix of juvenile and reworked Mesoproterozoic crust. Samples from different parts of the Paleozoic Dwyka Group in South Africa show significantly different provenance, with a western locality containing only zircon older than 2.0 Ga and a Neoarchean Nd model age. By contrast, eastern samples have Paleoproterozoic model ages and published detrital zircon ages are largely Mesoproterozoic and younger. Paleozoic samples from Bolivia have a Paleoproterozoic Nd model age. Overall, the difference between zircon initial Hf isotope compositions and the depleted mantle is smallest for Archean zircons, indicating major episodes of crustal reworking followed shortly after crust formation (perhaps reflecting the last stage of cratonization). Hf and Nd data together record major episodes of juvenile crust formation at 3.2, 2.8–2.7, 2.0–1.7, and 1.3–0.9 Ga, consistent with previously documented global crust formation events. The diamictites provide no evidence for pre-3.6 Ga felsic crust in these regions. [ABSTRACT FROM AUTHOR]

In order to constrain the detrital provenance of the siliciclastic rocks, palaeogeographic variations, and crustal growth history of central China, we carried out simultaneouslyin situU–Pb dating and trace element and Hf isotope analyses on 368 detrital zircons obtained from upper Permian–Triassic sandstones of the Songpan terrane, eastern Tibetan Plateau. Two groups of detrital zircons, i.e. magmatic and metamorphic in origin, have been identified based on cathodoluminescence images, zircon Ti-temperatures, and Th/U ratios. Our data suggest that the derivation of siliciclastic rocks in the Songpan terrane was mainly from the Qinling, Qilian, and Kunlun orogens, whereas the Yangtze and North China Cratons served as minor source areas during late Permian–Triassic times. The detrital zircons from Middle–Late Triassic siliciclastic rocks exhibit wide age spectra with two dominant populations of 230–600 Ma and >1600 Ma, peaking at ~1.8–1.9 Ga and ~2.4–2.5 Ga, suggestive of a derivation from the Qinling, Qilian, and Kunlun orogens and the Yangtze Craton being the minor source area. The proportions of detrital zircon populations from the northern Qinling, Qilian, and Kunlun orogens distinctly decreased during Middle–Late Triassic time, demonstrating that the initial uplift of the western Qinling occurred then and it could have blocked most of the detritus from the Qilian–northern Qinling orogens and North China Cratons into the main Songpan–Ganzi depositional basin. The relatively detrital zircon proportions of the Yangtze Craton source decreased during Early-Middle Late Triassic time, indicating that the Longmenshan orogen was probably being elevated, since the early Late Triassic and gradually formed a barrier between the Yangtze Craton and the Songpan terrane. In addition, our Lu–Hf isotopic results also reveal that the Phanerozoic magmatic rocks in central China had been the primary products of crustal reworking with insignificant formation of a juvenile crust. [ABSTRACT FROM AUTHOR]

We present data on the composition of metasedimentary rocks from the greenstone belt of the Onot terrane (Sharyzhalgay uplift) and results of U–Pb dating (SHRIMP II) and Lu–Hf isotope study of detrital zircon from garnet–staurolite schists. The metasedimentary rocks of the Onot greenstone belt are dominated by garnet- and staurolite-bearing schists alternating with amphibolites (metabasalts) in the upper part of the section. Compositionally the protoliths of garnet–staurolite schists correspond to sedimentary rocks, ranging from siltstone to pelitic mudstone. The trace-element characteristics of the garnet–staurolite schists indicate that the terrigenous material was derived from three different rock types, such as tonalite–trondhjemite plagiogneisses (elevated Gd/Yb ratios), mafic rocks (elevated Cr/Th ratios and reduced Th/Sc ratios), and felsic igneous rocks formed by crustal melting (the presence of a Eu minimum), which agrees with the set of potential source rocks from the Onot terrane. The age of predominant detrital zircon reflects the erosion of mainly Neoarchean igneous rocks; this fact, combined with the poor rounding of zircon and tectonically active sedimentation conditions accompanied by mafic volcanism, suggests that the probably depositional age is ca. 2.7 Ga. Older source rocks (2.80–3.35 Ga) contributed to the sediment deposition along with the Neoarchean ones. According to the Hf isotope composition of detrital zircon from the garnet–staurolite schists, the source provenances had different crustal prehistories. The source provenances include Paleoarchean and juvenile Neoarchean crust and rocks formed by the mixing of melts from ancient and juvenile crustal sources. [ABSTRACT FROM AUTHOR]

In this study, we use the U-Pb-Hf isotope composition of detrital zircon in metasedimentary rocks from the Western Dharwar Craton to identify older crusts, their nature, source, timing of extraction, and reworking. The samples come from the Holenarsipur region in the central and Sargur region in the southern part of the craton and belong to both the Sargur and the Bababudan Groups. Both detrital and metamorphic domains were identified in the zircon. The metamorphic overgrowths correspond to two age populations at 2536–2516 Ma, and 2478–2460 Ma. Rutile grains provide either concordant 2453 Ma, or discordant younger ages suggestive of thorough re-equilibration during metamorphism. Detrital zircon grains define notable clusters at 3685–3638 Ma, 3573–3524 Ma, 3471–3411 Ma, 3373–3341 Ma, 3277–3249 Ma, 3172–3148 Ma, 3084–2996 Ma, and 2659–2647 Ma which correspond to major episodes of granitoid crust formation in the craton. Based on detrital and metamorphic zircon populations, deposition of both the older Sargur Group and the basal unit of the younger Bababudan Group in the Holenarsipur region were broadly contemporaneous after c. 3160 Ma, while the sediments of the purported Sargur Group in the Sargur region were deposited after c. 2650 Ma. The new age data requires revision of the stratigraphic positions of the Sargur-type and Dharwar-type greenstone belt successions. The detrital zircon suites have both radiogenic and crust-like Hf isotopic compositions. However, the majority have radiogenic compositions that were acquired during major events of juvenile crust extraction between c. 3850 Ma and 3250 Ma. Strongly unradiogenic ɛHf (t) of some Paleoarchean detrital zircon require protoliths extracted from the mantle in the Hadean, but which persisted for a long period and contributed to granitoid formation in the Paleoarchean and the Mesoarchean. Mixing of juvenile magmas with preexisting crustal components also played a significant role in the petrogenesis of the granitoids. A distinct shift in the ɛHf (t) of the detrital zircon from chondritic to positive value at c. 3600 Ma is noted, reflecting a marked increase in the contribution of strongly depleted mantle reservoir to the source of the post-c. 3600 Ma granitoids. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cretaceous sedimentary rocks in the southwestern Ordos Basin, Northern China, contain detrital zircons with age peaks at 274, 438, 1852, and 2474 Ma. • These detrital zircons were primarily derived from the adjacent Alxa Block, the Qilian Orogenic Belt and the Yinshan Orogenic Belt, and were secondarily from the Qinling Orogenic Belt. • The Cretaceous sedimentary rocks were sourced from the Cretaceous paleo-uplifts and recycled from the underlying older rocks. • The migration of the Mesozoic sedimentary depocenter and provenance in the Ordos Basin was controlled by the regional compression of multiple directions. The Ordos Basin is located in the western part of the North China Craton, and was developed based on Paleozoic shallow marine sediments and Mesozoic continental deposits. In the southwestern Ordos Basin (SWOB), Paleozoic to Mesozoic sedimentary successions are well preserved and display variable deformation. However, the Cretaceous source-to-source evolution of the SWOB is poorly known but is significant to understand the tectonic evolution of the Ordos Basin. In this study, U–Pb ages and Hf isotopic analyses on detrital zircons from sandstones of the Cretaceous succession in the SWOB were performed, with an aim to trace the Cretaceous sediment provenances and the tectonic–paleogeographic configuration of the Ordos Basin. The new analyses clearly reveal four major age peaks for detrital zircons from Cretaceous sedimentary rocks in the SWOB: 274, 438, 1852, and 2474 Ma, and two minor peaks at 880–950 Ma and >3000 Ma. These zircons have ε Hf (t) values with a normal distribution from −15.8 to 11.4 and T DM2 ages with multiple peaks mostly at 2985–2720 Ma. Combined with the paleogeographic reconstruction and tectonic evolution of the Ordos Basin, the isotopic analyses prove that the detrital zircons in the Cretaceous succession were mostly sourced from the Alxa Block, Qilian Orogenic Belt, and Yinshan Orogenic Belt, and secondarily from the Qinling Orogenic Belt. Influenced by the formation of the Late Jurassic-Early Cretaceous paleo-uplifts, the Cretaceous sedimentary rocks in the SWOB were sourced from these paleo-uplifts and recycled from the underlying pre-Cretaceous rocks situated in the western Ordos Basin. The migration of the Mesozoic sedimentary depocenter and provenance in the Ordos Basin was controlled by the regional compression of multiple directions. [ABSTRACT FROM AUTHOR]

• The Qinling Orogen provided the source for sediments in the Western Hubei Basin. • The eastern part of the Mianlue Ocean was closed earlier than its western part. • The South China Block may have become a part of Pangea during the Late Permian-Middle Triassic. It is thought that the North China Block collided with Pangea earlier than the closure of the Mianlue Ocean between the South and North China Blocks. Therefore, the closure of the Mianlue Ocean, which induced the formation of the Qinling-Dabie Orogen, led to the amalgamation of the South China Block and Pangea. Yet, the timing of closure remains poorly constrained. We present detrital zircon U-Pb ages, trace element and Hf isotopic data for an upper Permian-lower Triassic sedimentary succession in the Western Hubei Basin, northern Yangtze Block, South China. One major age population of 250–330 Ma and four minor age populations of 400–650 Ma, 1030–1300 Ma, 1600–2000 Ma and 2300–2800 Ma were identified. Trace element and Hf isotopic data indicate zircons in the major age population may have sourced from active continental margins. When integrated with tectono-magmatic events of adjacent blocks, our data support that these detrital zircons were mainly sourced from the Qinling Orogen in the southern North China Block. Combined with continental subduction-related metamorphic events in the Dabie Terrane and syn -collisional granitoids in the West Qinling Belt, as well as the paleomagnetic data, our data support that the Mianlue Ocean experienced a scissors-like closure from the Late Permian in the east to the Middle Triassic in the west. In the middle of the Qinling-Dabie Orogen, the closure of the ocean took place earlier than ~255 Ma. This study supports the hypothesis that the South China Block became a part of Pangea during the Late Permian-Middle Triassic. [ABSTRACT FROM AUTHOR]

• The Paergangtag Group and Xinditag Group have similar detrital zircon compositions. • Negative εHf(t) values suggest crustal reworking at ca. 2.0 Ga in the Tarim Craton. • Tarim was in the interior of the Columbia Supercontinent and margin of the Rodinia. • Tarim Craton stayed tectonically stable for nearly 1 byr from ca. 1.8 to 0.9 Ga. The Proterozoic is the longest Eon in geological history and witnessed the assemblies and breakups of the Columbia and Rodinia supercontinents. The Tarim Craton has been proposed to be a building block of these supercontinents. However, its tectonic evolution during late Paleoproterozoic to earliest Neoproterozoic (ca. 1.8–0.8 Ga) has been poorly understood, due to the paucity of geological record. In this paper, we present U-Pb and Lu-Hf isotopic data for detrital zircons from the metasediments of the early Neoproterozoic Paergangtag Group and the Paleoproterozoic Xinditag Group in the Kuruktag area, northern Tarim Craton. Although formed approximately 1 billion years later, the Paergangtag Group contains detrital zircons almost identical to those in the Xinditag Group. LA-ICP-MS U-Pb dating yields a ca. 2.0 Ga age peak, as well as a group of older zircons of ca. 2.5 Ga in six samples from these two groups. Lu-Hf data show that the ca. 2.0 Ga zircons have variable εHf(t) values (−28.1 to 0.1), indicating the detritus were mostly derived from reworked continental crusts. The older zircons around 2.5 Ga have both negative and positive εHf(t) values (−28.5 to 9.5), indicating a prolonged and complicated crustal growth and reworking process in the source area. It is inferred that the zircons in these samples were likely derived from southeastern Tarim Craton, where a ca. 2.0 Ga orogenic event has been documented. The fact that the Neoproterozoic Paergangtag Group contains only Paleoproterozoic and older zircons suggests that the Tarim Craton was not involved in the Grenville Orogeny, which developed between the colliding continents in the interior of the Rodinia Supercontinent. In contrast, the Tarim Craton was probably on the periphery of the Rodinia Supercontinent and was involved in the peripheral subduction zone of the supercontinent shortly after the deposition of the Paergangtag Group. Our new data imply that the Tarim Craton might have been a tectonically stable continent for nearly 1 billion years from ca. 1.8 to 0.9 Ga. [ABSTRACT FROM AUTHOR]

Isotopic Lu-Hf and U-Pb systematics can provide important insights into the tectono-metamorphic processes that occurred in the source regions of sedimentary/metasedimentary units, helping to further clarify regional crustal evolution. The studied metasedimentary sequence is located in the southern Brasília Orogen, SE Brazil, a fold-and-thrust belt composed of a thick nappe stack transported towards the southern São Francisco Craton (SFC) during the Neoproterozoic. Adjacent to the Cratonic border is a reworked Neoproterozoic metasedimentary passive margin sequence, that includes the Carrancas succession, for which we present new U-Pb and Lu-Hf detrital zircon analyses (ca. 700 grains in total). Results yielded a maximum depositional age of 0.988 ± 0.013 Ga and an extensional tectonic setting for the precursor basin. Major source areas, constrained by comparing our data to isotopic analyses compiled from the existing literature, are probably located in the adjacent southern SFC. Lu-Hf analyses of Paleoproterozoic and Archean zircon grains, presented in this study, yielded similar results to those obtained for the basement of the SFC. However, important U-Pb age peaks found in this study do not have strong correlatives in the southern SFC (e.g. 1.84,1.87 and 1.88 Ga), with the exception of a few localized examples (e.g. Espinhaço I magmatism). These ages are abundant in the southwestern Congo Craton (CC), which was potentially relatively close to the studied area during sedimentation, since the SFC and CC probably constituted a single continental mass after the Paleoproterozoic until the opening of the south Atlantic in the Mesozoic. • U-Pb and Lu-Hf detrital zircon analysis. • Neoproterozoic (ca. 980 Ma) passive margin succession of the São Francisco Craton. • Lithostratigraphic repetition of formations due to folding corroborated by isotopic analyses. • Provenance assessment: the São Francisco and Congo cratons as likely sources. [ABSTRACT FROM AUTHOR]

• Rocks of North and South Liaohe Groups show similar detrital zircon age patterns. • Rocks of North and South Liaohe Groups have similar Hf isotope compositions. • Liaoji Grantiods and adjacent Archean basement serve as source for the Liaohe Groups. • Back-arc basin deposition occurred for corresponding formations of the Liaohe Groups. The Jiao-Liao-Ji Belt (JLJB) is one of the most important Paleoproterozoic orogenic belts, which is intervening between the Longgang and Nangrim-Liaonan blocks. The Liaohe Group is an important research subject for understanding the Paleoproterozoic tectonic setting and evolution of the JLJB. However, the relationship of depositional spatial and chronological distributions between the North and South Liaohe groups are still under debates. In this paper, we present geochronological and zircon Lu-Hf isotopic results of meta-sedimentary rocks from the Liaohe Group to decipher their provenance depositional ages and environment, as well as their tectonic significance on the JLJB. The detrital zircons from the corresponding formations, including the Li'eryu, Gaojiayu and Dashiqiao formations of the North and South Liaohe groups, show similarities in age patterns and Hf isotopic compositions. The detrital zircons from the Li'eryu Formation of the two groups display unimodal 207Pb/206Pb age peaks at ca. 2.2–2.1 Ga. On the other hand, detrital zircons from the Gaojiayu and Dashiqiao formations of the two groups, yield two dominating age peaks at ca. 2.2–2.1 and ~2.5 Ga. In summary, all detrital zircons with age peaks at ca. 2.2–2.1 Ga, have ε Hf (t) value of −6.99 to +9.41 and two-stage Hf depleted mantle ages (T DM2 model ages) of 3143 to 2137 Ma. The ~2.5 Ga detrital zircons however, have ε Hf (t) value and T DM2 model ages which widely range from −9.37 to +10.13 and from 349 to 2367 Ma, respectively. Geochronological results indicate that ca. 2.2–2.1 Ga zircons were derived from the Liaoji granitoids. The adjacent basement rocks of the Longgang and Liaonan-Nangrim blocks provide the major sources to detrital zircons that yield an age peak at ~2.5 Ga. Combined with previous studies, the new geochronological data suggest that the protoliths of the corresponding formations of the North and South Liaohe groups deposited their detritus progressively in a back-arc basin. The Liaoji granitoids are the main sources providing detritus for the Li'eryu Formation. Subsequently, clastic sediments transported from the Longgang and Liaonan blocks, as well as from the Liaoji granitoids, were successively deposited and provided sources to the Gaojiayu and Dashiqiao formations. [ABSTRACT FROM AUTHOR]

Carboniferous–Permian detrital zircons are recognized in the Upper Paleozoic of the whole Ordos Basin. Previous studies revealed that these Carboniferous–Permian zircons occurred in the Northern Ordos Basin mainly originated from the Yinshan Block. What has not been well documented until now is where this period's zircons in the Southern Ordos Basin came from, and very little discussion about their provenance. To identify the provenance of the detrital zircons dating from ~350 to 260 Ma, five sandstone samples from the Shan 1 Member of Shanxi Formation and eight sandstone samples from the He 8 Member of Shihezi Formation were analyzed for detrital zircon U-Pb age dating and in situ Lu-Hf isotopic compositions. The results indicate that the two age clusters of 520–378 Ma and ~350–260 Ma in the Southern Ordos Basin most likely derived from the North Qinling Orogenic Belt–North Qilian Orogenic Belt and the North Qinling Orogenic Belt, respectively. Furthermore, we propose that the zircons aging ~320–260 Ma are representative of the important tectonothermal events occurred in the North Qinling Orogenic Belt during the Late Paleozoic. [ABSTRACT FROM AUTHOR]

A total of 334 sets of age data were obtained from the three sandstone samples, which range from 2598 to 330 Ma. Ages of the zircon grains fall into three major groups: Paleozoic (<540 Ma) (Fig. A), Neoproterozoic to late Precambrian (540–1800 Ma), and early Precambrian (>1800 Ma) (Fig. B). The Hf isotope data show that the detrital zircon source probably shares similar origin with the Jinwozi granite (Fig. C). These rocks may have formed in the early Paleozoic Caledonian Orogeny, during which the supercontinents of Gondwana and Laurasia assembled. This mountain building process may have provided the detritus for the clastic rocks of the Jinwozi Formation. • Au veins or lodes in Jinwozi deposit occur in Jinwozi Formation or Jinwozi granite. • Jinwozi Formation deposited after 330 Ma, postdates the Silurian Jinwozi granite. • The debris of Jinwozi Formation were mainly sourced from mid-Paleozoic granites. • The strongest crustal growth occurred in mid-Paleozoic (420 ± 50 Ma) in Beishan area. The Jinwozi deposit is the most economically important gold (Au) deposit in the Beishan Orogen (Eastern Xinjiang, NW China). The Au orebodies occur as quartz veins or altered lodes in the Jinwozi Formation clastic rocks and the Jinwozi granite. The age, detrital source and tectonic setting of the Jinwozi Formation, however, have not been well understood. In this paper, we reported new LA–ICP MS detrital zircon U–Pb ages and Lu–Hf isotopes of ore-hosted clastic rock of the Jinwozi Formation. Detrital zircons from three samples yield 334 U–Pb ages varied from 330 to 2598 Ma, showing complex detrital sources. The youngest detrital zircon population suggests that the Jinwozi Formation deposited no earlier than 330 Ma in the Late Carboniferous or Permian. The majority of the detrital zircons (291 out of 334) have ages between 330 and 533 Ma, suggesting a dominant Paleozoic detrital source. Much of these age data (282 out of 334) range from 470 to 370 Ma, broadly coeval with the zircon U–Pb ages of the Jinwozi granite. Zircon Hf isotope data also implicate their similar origin to the Jinwozi granite. The source rocks, as well as the Jinwozi granite, may have formed in the Early Paleozoic Caledonian Orogeny, during which the supercontinents of Gondwana and Laurasia assembled. This orogeny process may have provided plenty of detritus for the clastic rocks of the Jinwozi Formation. Precambrian detrital zircon ages from the Jinwozi Formation cluster around 2400–2600 Ma, 1800–2100 Ma, 800–1300 Ma, which corresponds to the supercontinent assembly events of Kenor, Columbia and Rodinia, respectively. The age populations of 2200–2300 Ma and 600–660 Ma are possibly related to the breakup of Kenor and Rodinia supercontinents. This understangding is supported by zircon Hf isotope data. [ABSTRACT FROM AUTHOR]

Late Carboniferous bauxite is widely developed on the North China Craton (NCC), and is referred to as the "G" layer bauxite. The bauxite ores of the southern NCC are closely related to the tectonic evolution of the NCC and its neighboring North Qinling Belt (NQB) to the south. In this study, based on the geological and mineralogical observations, we used the U–Pb and Hf isotopes of detrital zircons and chemical compositions of detrital rutiles from the Gunziying and Shibanhe bauxite deposits, along the southern margin of the NCC to study the metallogenic process of bauxite ores and their tectonic implications. One and two bauxite ore layers were observed in the Gunziying and Shibanhe bauixte deposits, respectively. The bauxite ore is dominated by diaspore, illite, anatase, kaolinite, pyrite, zircon, and rutile. Analyses of detrital zircons revealed that the largest group (∼432–515 Ma, at a peak age of ∼450 Ma) is spread throughout the Late Carboniferous bauxite deposits, with εHf(t) values of −5.7–21.4, similar to the zircons from the NQB. Similarly, the detrital zircons with peak ages of ∼950 Ma and age clusters at ∼1.1 Ga, ∼1.3 Ga, and ∼1.8 Ga as well as those ranging in age from 635 to 797 Ma, also exhibited εHf(t) values similar to the zircons from the NQB. In addition, the results suggested that 62 (73%) and 75 (88.2%) of detrital rutiles showed metapelitic protoliths and amphibolite/eclogite facies temperatures, respectively, while 23 (27%) and 10 (11.8%) exhibited metamafic protoliths and granulite facies temperatures, respectively. Based on the results above, we propose that the provenance of the bauxite ores on the southern margin of the NCC is primarily from the NQB. The dominant contributors were the Neoproterozoic Kuanping Group and the Meso–Neoproterozoic Qinling Group. The Archean-Proterozoic metamorphic rocks in the paleo-uplifts of the NCC were also likely involved in the bauxite formation. A probable outline of the bauxite-formation process on the southern NCC, former weathered residuals and subsequent deposition, is proposed; and a reasonable interpretation that the NQB was accreted to the NCC in the Late Carboniferous and formed a northward lying slope basin within the NCC, is supported. Image 1 • New constraints on the source of the NCC bauxite ores are proposed. • Mainly material transport from the North Qinling and Kuanping Group. • Bauxitic formation most likely weathered residuals and deposited. • Late Paleozoic Tectonics resulted in the "G" bauxites throughout the NCC. [ABSTRACT FROM AUTHOR]

• The Mesozoic Linbuzong Formation, part of the Gangdese region within the southern Lhasa sub-terrane, was deposited after 149 Ma. • During the Late Jurassic to very Early Cretaceous, the central Lhasa sub-terrane had a relatively high relief. • The central Lhasa sub-terrane was the dominant source area of the back-arc basin containing the Linbuzong Formation during the Late Jurassic to Early Cretaceous rather than the Gangdese arc. Sedimentary rocks in the Gangdese magmatic arc document a long but poorly constrained series of tectonic events that led to basin formation. We investigate one of these events by using detrital zircon grains from Mesozoic sedimentary rocks from the Linbuzong Formation located within the Gangdese magmatic arc. Our aims are to determine the provenance of the rocks in this back-arc basin and to document the paleo-topographical uplift of the Gangdese region in southern Tibet. Detrital zircons from the Linbuzong Formation, located in the middle-eastern segment of the southern Lhasa sub-terrane, have ages in four dominant populations: 140–300 Ma, 480–700 Ma, 1000–1250 Ma, and 1400–1700 Ma. The youngest detrital zircon cluster has a weighted age of ca. 149 Ma which, in conjunction with previously published data, indicates that sedimentary rocks in the Linbuzong Formation were deposited after 149 Ma. The youngest detrital zircon grains have low 176Hf/177Hf isotopic ratios and negative ε Hf (t) values, similar to igneous zircons from the central Lhasa sub-terrane which is considered to be the predominant source for sediments. However, few zircon grains from the youngest age cluster have high 176Hf/177Hf ratios with significantly positive ε Hf (t) values, suggesting derivation of some sediments from the southern Lhasa sub-terrane, primarily the Gangdese magmatic arc. Combined with the evidence for two conspicuous age populations (480–700 Ma and 1000–1250 Ma) and the Hf isotopic characteristics of the Linbuzong Formation, we propose that the Carboniferous-Permian metasedimentary rocks from the central Lhasa sub-terrane serve as the main source of sediments for the Linbuzong Formation. We conclude that the central Lhasa sub-terrane was exhumed to the surface and attained a high relief, whereas the Gangdese magmatic arc had a relatively low relief (near sea-level) during the Late Jurassic to the Early Cretaceous. [ABSTRACT FROM AUTHOR]

• Provenances of Permo-Triassic clastic rocks in eastern CAOB change from single to bidirectional. • The mixing of the Angaran and Cathaysian floras occurred during the Late Permian-Middle Triassic. • The PAO closed via a scissor-like closure model from west to east with bidirectional subduction. The mixture of the Cathaysian and Angaran floras signifies the evolution of the Paleo-Asian Ocean (PAO). In this study, we present new zircon U-Pb-Hf isotope analyses from the Jiefangcun Formation, Sidonggou Formation, Kedao Group, and Kaishantun Formation in the Yanbian area, NE China. The Kaishantun Formation contains the Kaishantun flora, which is dominated by the Cathaysian flora with a few Angaran elements. The Jiefangcun Formation is characterized by the Jiefangcun flora, which is dominated by the Angaran taxa and contains some Cathaysian elements. The ages of these strata are widely accepted as Permian. However, in this study, the youngest zircon ages of the rock samples from the Jiefangcun Formation, Kedao Group and Sidonggou Formation are 243–245 Ma. Only the Kaishantun Formation is assigned to the Late Permian. The Kaishantun Formation has age peaks at 758, 934, 1856, and 2493 Ma with negative ε Hf (t) values, and this formation is therefore mainly derived from the North China Craton (NCC). In contrast, the Kedao Group and Jiefangcun Formation have zircon age peaks at ~260, 338 and ~460 Ma with positive and negative ε Hf (t) values, at 800–1000 Ma with mostly positive ε Hf (t) values, and at ~1800 Ma with positive and negative ε Hf (t) values, which suggest bidirectional provenances, including the Jiamusi-Mongolia Block and the NCC. Thus, the mixing between the Angaran and Cathaysian floras occurred during the Late Permian-Middle Triassic, suggesting a scissor-like closure model of the PAO, and the Solonker suture zone extends eastward to the Yanbian area with bidirectional subduction of the PAO. [ABSTRACT FROM AUTHOR]