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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]

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]

[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]

• 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 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]