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• First report of Paleoproterozoic incipient charnockite from the Yeongnam Massif. • Incipient charnockite is a peak-metamorphic product of biotite-dehydration melting. • Prolonged granitic magmatism, granulite-facies metamorphism, and fluid influx at ca. 1.88–1.84 Ga. • Paleoproterozoic hot orogenesis in the North China Craton linked to the Yeongnam Massif. The incipient charnockite or orthopyroxene-bearing granitic orthogneiss is a relatively common constituent in ancient granulite-facies terranes, and its formation has been often attributed to an influx of CO 2 -rich fluid or a removal of aqueous melt. Temporal relationship between the orthopyroxene formation and the fluid or melt migration, however, remains debatable. Here we report the first finding of incipient charnockite hosted by garnet-biotite-bearing granitic gneisses in the Sancheong–Hadong anorthosite complex, Yeongnam Massif. Both lithologies preserve a variety of field and microstructural evidence for partial melting and subsequent melt crystallization, as manifested by granitic leucosomes and biotite-rich residua. Based on the phase equilibria modeling and geothermobarometric calculation, peak metamorphic conditions of migmatities were estimated to be 5.4–6.0 kbar and 800–850 °C, which led to the biotite dehydration melting together with the orthopyroxene formation in incipient charnockite. Sensitive high-resolution ion microprobe (SHRIMP) U–Pb analyses of zircon from an incipient charnockite and a host gneiss yielded the weighted mean 207Pb/206Pb ages identical within errors; 1880 ± 5 Ma and 1872 ± 6 Ma for the cores, and 1862 ± 4 Ma and 1861 ± 4 Ma for the rims, respectively. The former is interpreted to represent the time for magmatic crystallization of granitic protoliths, whereas the latter for subsequent anatexis typified by peritectic growth of orthopyroxene. Such a timeline is consistent with two distinct thermal events previously reported from the Sancheong-Hadong anorthosite complex. By contrast, monazite grains from a biotite-bearing granitic gneiss in the charnockite zone yielded the weighted mean 207Pb/206Pb ages of 1866 ± 14 Ma and 1835 ± 11 Ma for the core and rim, respectively. The latter is consistent with 1842 ± 8 Ma, estimated from monazite neoblasts of incipient charnockite. The monazite growth during a post-peak metamorphic stage at ca. 1.84 Ga is attributed to a fluid influx event, apparently concentrated in the charnockite zone. The charnockite formation in the Yeongnam Massif further attests to the longevity (>ca. 40 m.y.) of hot orogenesis that has governed the Paleoproterozoic crustal evolution in eastern North China Craton. [ABSTRACT FROM AUTHOR]

• Proposition of segmentation of the Paranoá Group in sequences and tectonic stages. • Geochronological data to establish the source areas of the Paranoá basin. • Multi-dimensional scaling of detrital zircon to evaluate Precambrian basins. Some of Proterozoic basin data are commonly difficult to assess due to the complexity of tectonic processes and lack of volcanic rocks and fossil record. The Mesoproterozoic Paranoá Basin in Central Brazil was investigated through stratigraphic framework integration, depositional environmental analysis and with detrital zircon and statistical analysis. Paranoá Group was evolved in three phases: i) Proto-Basin Stage represents the basal succession, including the transition from the continental environment (alluvial fans) to shallow water platform conditions; ii) Expansion Basin Stage, which includes the most significant sediment thickness and the essential contrasting depositional environment, including tide-dominated platform, storm dominated platform, supratidal and foreshore conditions and iii) Final Basin Stage represents the shallower environment condition, including mix siliciclastic – carbonate successions. The stages are related to different depositional space creation mechanisms: mechanical subsidence to the Proto-Basin Stage, thermo-flexural subsidence to the Expansion Basin Stage, and flexural subsidence to the Final Basin Stage. The detrital zircon data allied with multidimensional scale were crucial to constrain the basin's tectonic evolution. For the basal succession, the maximum depositional age is ∼1.5 Ga with the local crystalline basement (Aurumina Suite tonalitic and granodioritic gneiss). The source areas changed during the expansion stage, in which the sedimentary successions accumulated during this stage present maximum depositional age of ∼1.3 Ga and a widespread distribution pattern. In the final phase, the maximum depositional age is ∼1.1 Ga, including a complex distribution of ages representative of different source areas. The new and compiled data presented in this study provide new insights about the Goiás-Pharusian opening and implications on the configuration in the western margin of the São Francisco Craton. [ABSTRACT FROM AUTHOR]

• Cuxiú Formation sandstone of Aquiri region was deposited between 2705 and 2665 Ma. • Hinterland consisted of Neo- to Paleoarchaean (2705–3600 Ma) granitoids. • Hf model ages indicate reworking of late Hadean to Mesoarchean (4.0–3.0 Ga) crust. • Zircon ages and shapes suggest erosion of heterogeneous basement and short transport distance. • Correlation of zircon size vs. roundness results from fluvial transport. Provenance studies are commonly based on in situ U–Pb dating and Hf isotope analyses of detrital zircon grains, while leaving shape parameters unconsidered, even though these can provide valuable information about the hinterland and detritus transport. This is demonstrated herein by presenting a comprehensive data set derived from approximately 950 detrital zircon grains from three quartzite samples of the Cuxiú Formation of the Aquiri region, which is part of the eastern realm of the Amazon Craton. The data set combines results of zircon U–Th–Pb–Hf isotope analyses with zircon shape, and some physical parameters, including length, width, aspect ratio, roundness, typology, alpha-decay dose and density. Zircon U–Pb ages and field relationships indicate that pebbly sandstones of the Cuxiú Formation were deposited during the Neoarchaean between 2705 and 2665 Ma, likely in a fluvial or near-shoreline environment of a rift basin, with zircon grains supplied from igneous rocks of the surrounding Amazon Craton. The detrital zircon grains record crystallisation ages of 3100–2800 Ma (74%), and subordinately of 2800–2700 Ma (13%) and 3600–3100 Ma (3%). Hafnium isotope analyses further suggest crust formation in the hinterland at 4.01–3.65 Ga (14%), 3.60–3.10 Ga (85%) and 2.95 Ga (1%). Well preserved euhedral shapes of more than 50% of the detrital zircon grains, independent of U–Pb ages, suggest fast, direct supply from heterogeneous Archaean basement sources to the sedimentary basin, with a short-distance transport, plausibly in a fluvial setting. Correlation of zircon roundness with width in the size range from 50 to 150 µm indicates more intense abrasion of larger zircon grains compared to smaller ones, reflecting difference in transport mechanisms – i.e., abrasive-rolling transport vs. non-abrasive suspension transport. Similar average values for length (~120 µm), width (~66 µm), aspect ratio (1.9) and roundness (~2.5), obtained from zircon grains of very different ages (3600–2700 Ma), as well as log-normal distribution of the width parameter, suggest thorough hydrodynamic sorting during transport. Zircon typology analysis reveals a wide range of combinations of {1 0 0}:{1 1 0} prism faces with{1 0 1}:{3 0 1}:{2 1 1} pyramids, pointing to zircon crystallisation from 900 to 600 °C (average 755 °C). Uranium–Th contents indicate low α-decay doses of ≪1 × 10−15 decay events/mg for all zircon grains by the time of deposition, providing an additional explanation for the excellent zircon preservation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The provenance of most of the Liaohe group characterized by arc magmatic rocks and Archean basements. • Magmatic activities at 2100–2000 Ma in the Nangrim and North Gyeonggi blocks contribute to the upper Liaohe group. • Sedimentary, geochronological, and geochemical evidence supports existence of arcs and a back-arc basin. • A four-stage back-arc basin model is proposed tectonic evolution of the LPOB. The Liaodong Paleoproterozoic orogenic belt (LPOB), as part of the eastern North China Craton (NCC), is the result of global collision during the amalgamation of the Columbia supercontinent. Tectonics of the LPOB thus becomes the key to the understanding of the tectonic evolution of the NCC, and may provide important information on the assembly of the supercontinent. Detailed geochronological and geochemical analysis on detrital zircons from the Liaohe group is conducted to unravel the tectonic attribute of the major constituent, i.e., the Liaohe group within the LPOB. The results show that the U-Pb ages of detrital zircons from the Langzishan, Li'eryu, Gaojiayu and Dashiqiao formations at the middle-lower parts of the Liaohe group are mainly characterized by peaks at ~ 2500 and 2200–2100 Ma. However, the ages of detrital zircons from the Gaixian formation at the upper part are peaked at 2100–2000 Ma. The age data indicate that the Archean basement rocks and Paleoproterozoic magmatic activities at 2200–2100 Ma variably provide sources for sediments of the middle-lower Liaohe group. However, sediments of the Gaxian formation at the upper part of the Liaohe group are mainly derived from magmatic activities from the Nangrim and North Gyeonggi blocks at 2100–2000 Ma. The source characteristics of the Liaohe group highlight the importance of back-arc extension in the evolution of the LPOB. The tectonic evolution of the LPOB is, therefore, subdivided into four stages, i.e. early back-arc extension stage (2200–2080 Ma), transitional stage (2080–1940 Ma), main orogenic deformation (1940–1840 Ma) and post-orogenic plutonic emplacement (after 1840 Ma). [ABSTRACT FROM AUTHOR]

• The HP mafic, intermediate, and felsic granulites were discovered along the TNCO. • The formation ages of the Changyukou meta-supracrustal sequences are Neoarchean at ~ 2.5–2.55 Ga. • The HP granulites underwent high pressure granulite facies metamorphism at ~ 1.9 Ga. • The low-18O signature of the zircons was captured in the Neoarchean. • The TNCO was formed by a long-lived tectono-metamorphic event from ~ 1.9 Ga to ~ 1.8 Ga. High-pressure (HP) mafic granulites are widely distributed along the Trans-North China Orogen (TNCO), and they provide important insights into the timing and tectonic processes involved in the formation of the TNCO. We discovered three types of HP granulite, including mafic, intermediate, and felsic granulites, exposed in Chicheng area, in the northern segment of the TNCO. Their mineral assemblages of prograde, peak, and post-peak metamorphic stages were identified based on petrographic investigations. SIMS U-Pb zircon analyses yielded an upper intercept age of 2547 ± 38 Ma and a lower intercept age of 1916 ± 100 Ma for one HP mafic granulite and a discordant 207Pb/206Pb age of 2479 Ma with a weighted mean 207Pb/206Pb age of 1905 ± 9 Ma for the other HP mafic granulite. For the HP intermediate granulite, an upper intercept age of 2544 ± 20 Ma was obtained. The HP felsic granulite yielded an upper intercept age of 2524 ± 23 Ma and a concordant 207Pb/206Pb age of 1906–1907 Ma. These results reveal that the protoliths of HP granulites were formed at ~ 2.5–2.55 Ga and underwent high pressure granulite facies metamorphism at ~ 1.9 Ga. The elevated Hf isotopic compositions of the metamorphic zircons from two granulite samples indicate that metamorphic fluids that have high 176Hf/ 177Hf ratios but low 176Lu/177Hf ratios were involved in their metamorphism. The low 18O isotopic features of the zircons from the intermediate granulite suggest alteration by δ18O-depleted seawater or meteoric fluids at high temperatures. By integrating geochronological data from previous studies, we infer that the formation of the TNCO may have begun as early as ~ 1.9 Ga and lasted until ~ 1.8 Ga, supporting the hypothesis that it was formed by a long-lived tectono-metamorphic event [ABSTRACT FROM AUTHOR]

[Display omitted] • A new arc-related unit is characterized in the Borborema Province, NE Brazil. • Pacatuba-Maranguape Complex comprises plutonic and metaplutonic rocks of granodioritic-granitic composition. • Calc-alkaline, slightly peraluminous, I-type granitoids formed after hybrid (crust + mantle) sources. • Zircon U-Pb geochronology shows crystallization ages of ca. 675 Ma-610 Ma. • A record of a magmatic flare-up at 660–620 Ma in the Santa Quitéria Magmatic Arc. The amalgamation of continental masses during the formation of West Gondwana at the end of the Neoproterozoic (ca. 0.6 Ga) resulted in the closure of oceans and associated generation of magmatic arcs. To better understand episodes of high magma production, compositional and isotopic evolution of arc magmatism in the western active margin of Gondwana, this work presents new U-Pb zircon ages, lithogeochemistry, whole-rock Nd and in situ zircon Hf isotopes from plutonic and metaplutonic rocks of a dismembered arc-related unit (Pacatuba-Maranguape Complex) from the Ceará Central Domain, Borborema Province (NE Brazil). The Pacatuba-Maranguape Complex is exposed in the northeastern portion of the Ceará Central Domain and comprises pre- to late-tectonic granitoids bordered by migmatitic-gneisses that have experienced variable partial melting and deformation. Zircon U-Pb analyses yielded concordant ages of 675 Ma, 655–640 Ma, 630–625 Ma and 610 Ma, with inherited grains of 880–700 Ma, 700–650 Ma and 2200–2000 Ma. Geochemically, the granitoids are medium- to high-K calc-alkaline, metaluminous to slightly peraluminous, magnesian and calc-alkalic to alkali-calcic. Lu-Hf and Sm-Nd model ages provided T DM (Hf) model ages between 920 Ma and 1470 Ma with ɛHf (t) values of + 12.75 to −5.44, and T DM (Nd) values between 950 Ma and 1470 Ma with ɛNd (t) values between −1.06 and + 4.35. These data indicate that these granitoids were generated from the mixture of juvenile magmas and older crustal components on an active continental margin setting. Petrogenetic and geochronological constraints indicate a synchronous evolution with the Santa Quitéria Magmatic Arc, exposed approximately 100 km to the west. The compilation of geochronological and geochemical data from the Pacatuba-Maranguape Complex and the Santa Quitéria Arc suggests that arc magmatism developed mainly as a result of a magmatic flare-up between 660 and 620 Ma during the subduction of the Goiás-Pharusian oceanic crust in the central portion of West Gondwana. [ABSTRACT FROM AUTHOR]

• Siderian-Rhyacian orogeny formed the Juiz de Fora Complex. • Juvenile accretion at ca. 2.44 Ga marks a primitive intra-oceanic arc setting. • Coeval TTG-Sanukitoid suites at ca. 2.20 Ga marks the mature arc setting. • ca. 2.03 Ga metamorphic zircon records the collision with the Mantiqueira Complex. The Juiz de Fora Complex (JFC) is one of the basement units of the Occidental Terrane, Central Ribeira belt, in the Neoproterozoic framework of Western Gondwana, regarded as part of the reworked border of the São Francisco Paleocontinent. The JFC comprises Paleoproterozoic granitoid rocks with TTG, calc-alkaline, sanukitoid, and tholeiite-type geochemical compositions. They exhibit complex deformational fabrics associated with two episodes of granulite-facies metamorphism, occuring in the early Orosirian and the Ediacaran. The new U-Pb (SHRIMP) isotopic ages and Lu-Hf (LA-MC-ICPMS) data combined with available lithogeochemical, whole-rock Sm-Nd and Rb-Sr isotopic data constrain the tectonic evolution of the JFC to a Siderian-Rhyacian evolved arc system. Five samples were selected for U-Pb geochronology and Lu-Hf analysis on zircon grains: a low-K tholeiite, one TTG, two sanukitoids, and a mafic tholeiite. Combined whole-rock Sm-Nd, Rb-Sr isotopes, and zircon Lu-Hf isotopic data suggest the following evolution: an initial moderately juvenile (2445 Ma) low-K tholeiitic magmatism (εNd(t) of − 0.1; εHf(t) from − 8 to + 3), followed by a moderately juvenile to evolved (2200–2182 Ma) coeval TTG-sanukitoid pulse (εNd(t) from − 0.6 to − 4.8; εHf(t) from − 11.7 to + 2.5), and eventually by a moderately juvenile (2130 Ma) tholeiitic magmatism (εNd(t) = − 0.05). The integrated information provides preliminary petrogenetic insights for these magmatic episodes, such as interaction between mantle sources and supracrustal subducted material, melting of the oceanic slab, and crustal assimilation. A ca. 2035 Ma collisional granulite event recorded in metamorphic rims and neoformed zircon grains in leucosomes, possibly marks the amalgamation of the JFC onto the Mantiqueira Complex. Geochronological and isotopic correlations with coeval terranes of the Minas-Bahia Orogen in the Brazilian and African counterparts are addressed for tectonic implications at a broader scale. [ABSTRACT FROM AUTHOR]

• SJC experienced multiple magmatism of ~2.78, ~2.69 and ~2.55 Ga. • Neoarchean magma derived from episodic juvenile crust growth and crustal reworking. • Recycling of sediments was not intense or extensive in SJC during Neoarchean. • A bottom-up tectonic regime related to plume activity is favored for NCC in Neoarchean. Recent advances in high-precision in-situ analysis of zircon U-Pb-Hf-O isotopes have significantly improved our approach to studying the origin and evolution of Archean crust. This study presents high-precision in-situ zircon U-Pb-Hf-O isotopes for the Southern Jilin Complex (SJC) on the northeastern margin of the North China Craton (NCC) and explores the potential of such an integrated approach in understanding the Archean crust evolution and its tectonic implications. The SJC consists mainly of Archean granitoid gneisses hosting minor supracrustal rock xenoliths. Zircon U-Pb data from representative lithologies reveal three episodes of magmatism at ~2.78, ~2.69 and ~2.55 Ga, respectively. The former two granitoid magmatic events are recognized for the first time in NE NCC, while the latest one is widespread over the NCC. All metamorphic zircon domains document similar metamorphic ages of 2.51–2.48 Ga, consistent with the widespread metamorphism of ~2.50 Ga in the NCC. Most concordant magmatic zircons preserve "mantle-like" O isotopic signatures, indicating the magma sources were not contaminated by large amounts of high δ18O supracrustal sediments. Hf depleted mantle model ages of magmatic zircons display one predominant peak at 2.9–2.8 Ga and two subordinate peaks at 3.3–3.2 Ga and 2.7–2.6 Ga, indicating possible episodic crust-mantle differentiation in Southern Jilin. Integrated zircon U-Pb-O-Hf data from the SJC suggest that magma sources were mainly derived from multiple episodes of reworking of juvenile or ancient crust with mantle component addition, while recycling of sediments was trivial during the Neoarchean in this region. The spatial–temporal relations of magmatism, lack of supracrustal addition to magma sources, and other geological evidence from the NCC are in favor of a bottom-up geodynamic regime possibly related to plume activities, arguing against a widespread top-down mechanism involving modern-style subduction in the NCC during the Neoarchean. [ABSTRACT FROM AUTHOR]

• The Kashala Formation deposited during Late Triassic age. • Archean to late Paleozoic detrital zircon grains in sediments of the Kashala Formation. • U-Pb age and Hf isotopes suggest secular and episodic continental reworking and growth from Paleoarchean to Early Paleozoic. • Detrital zircon grains suggest proximal sources by second cycle of transportation and deposition during accumulation of the Kashala Formation. Detrital zircon analysis of the Triassic Kashala Formation of the Alpurai Group in Swat, Pakistan, west of Indus syntaxis, record Archean to Paleozoic ages. The U-Pb age spectra show distinctive age clusters at 3510–3100 Ma, 2700–2400 Ma, 1750–1500 Ma, 1350–750 Ma, 700–600 Ma and 580–470 Ma, with one youngest age of 229 Ma, suggesting secular and episodic continental growth. The prominent negative εHf (t) values indicate dominantly crustal reworking together with a minor contribution from a juvenile crust. The age pattern is similar to the detrital zircon from Tethyan Himalaya and South India, showing two major peaks at 926 Ma and 532 Ma, and corresponding to Greenville and Pan-African orogenies, respectively. The U-Pb age peaks between ca. 1750–1600 Ma and 900–750 Ma are correlated well with the peaks of detrital zircon from Precambrian and Ordovician rocks in the Hazara region. Detrital zircon analysis suggests proximal source areas. Based on combined U-Pb and Hf isotope analysis and grain morphology, Paleoproterozoic detrital zircon grains were derived from basement rocks of the Besham Complex, which is presently exposed in the Indus syntaxis. The zircon trace element geochemistry reveals mainly felsic and mafic igneous rocks of the continental crust, suggesting that proximal Proterozoic-Paleozoic intrusions in the Swat and Hazara regions as a possible source. [ABSTRACT FROM AUTHOR]

Lu-Hf laser ablation – multi-collector – inductively coupled plasma – mass spectrometry (LA-MC-ICP-MS) analysis was conducted on ~1800 detrital zircon grains from successor basins of the Archean Abitibi and Pontiac subprovinces of Ontario and Quebec, Canada, and paired with previous U-Pb LA-MC-ICP-MS analyses of the same grains. Results are used to constrain the isotopic character of magmatic source domains of the zircon grains to establish the sedimentary provenance of the ~2690–2670 Ma successor basins, to provide constraints on terrane configurations and amalgamations at the time of basin formation, and to assess their significance for the record of crust-mantle growth in the region. The majority of results (95%) yield ɛ Hf values of + 1 to + 10 for ~2850–2675 Ma zircon, and clusters along compositions of the Archean depleted mantle (DM), which is based on projections of modern MORB compositions. Subordinate results, comprising ~2% of the data set, yielded values (ɛ Hf > +10) corresponding to extremely depleted mantle compositions, reflecting anomalously depleted sources in the ~2950–2670 Ma age range. The remaining 3% correspond to chondritic uniform reservoir (CHUR)-like to negative ɛ Hf values that reflect primitive sources and/or evolved magmas in zircon that crystallized in the ~3250–3050 Ma and ~2950–2670 Ma age ranges. While Neoarchean grains dominate the data set (~88%), approximately 12% are Mesoarchean. The Lu-Hf data collected on these zircon grains, when compared with published isotopic results, preserve signatures indicative of derivation from exotic crustal domains juxtaposed during ~2690–2670 Ma amalgamation of the southern Superior Province. Since depleted compositions are characteristic of Neoarchean and Mesoarchean zircon groups in the southern Superior Province, and sources include local and distal domains that were likely separated by many 100s of kilometers prior to amalgamation, it is inferred that a depleted upper mantle reservoir was not only well-established, but prevalent in the mantle below each of these areas during their construction. Based on the predominant Hf isotope signatures in the detrital zircon results and predicted isotopic trends produced by probable geodynamic mechanisms, crustal growth by direct differentiation from a depleted mantle reservoir is likely to have been moderated by subduction-accretion processes. [ABSTRACT FROM AUTHOR]

• Zircon U/Pb dating provides two main populations: 1370–1420 Ma and 950–1000 Ma. • Th/U ratios and luminescence signal suggest anatectic conditions for the young zircons. • An intracontinental setting is proposed for these granites. • Recycling of older material is evidenced by the inherited ages in several samples. The Karagwe-Ankole belt (KAB) is a poorly understood deformation belt in the Great Lakes area of Central Africa, with several hypotheses put forward to explain the emplacement of the various generations of granites. The youngest generation of granites (G4; 1000 Ma) are spatially associated with Sn-W-Ta ore deposits, and are considered as the parental granites. The paragenesis of these mineral resources have been extensively scrutinised, but the geodynamic context and characterisation of these parental granites has been neglected. Tectonic models for the formation of this plutonic suite range from an intra-cratonic to full-scale continent–continent collision setting. In this study, the G4 intrusive suite of the KAB granites, are characterised based on whole-rock geochemical analysis and U-Pb zircon dating. Two main populations of U-Pb zircon ages are identified in the G4 granites at 1370–1420 Ma and 950–1020 Ma. The older population is attributed to inheritance of the bimodal magmatic Kibaran event, while the younger population is ascribed to the new crystallisation. G4 granites contain xenocrystic zircon, indicating inheritance of older granites or basement rocks. G4 granites are, however, much more differentiated compared to older Kibaran granites, containing higher K and Rb and lower Ca, Sr and Ba concentrations, which implicates recycling of older crustal material. The variable geochemistry, as well as the different proportions of xenocrystic zircons in the different granite bodies, suggest melting was highly localised and derived from a highly heterogeneous source region, for which an intracontinental setting is favoured. The Th/U ratios of the parental granites are lower than 0.1, which would suggest a metamorphic origin of the granites. Together with the low luminescence signal of these zircons an anatectic origin of the melt is considered, implying that the parental granites could be considered more like migmatites rather than actual granites formed by fractionation out of large magma chambers. [ABSTRACT FROM AUTHOR]

• Detrital zircon analysis of Neoproterozoic Dom Feliciano Belt supracrustal rocks. • Minimum age constraint for sedimentation into Brusque Complex rift basin at ca. 810 Ma. • Mesoproterozoic zircon age fractions reveal major African sedimentary protosources. • Brusque Complex detrital zircon record correlates with Kaoko Belt and Porongos Complex. • Data show close proximity between the Luis Alves and Congo cratons at Rodinia breakup. Neoproterozoic metasedimentary rocks in the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system record sedimentation from the breakup of Rodinia to the amalgamation of Gondwana, and thus provide ideal subjects for investigation of the mutual pre-orogenic positions of rifted margins of the African and South American cratonic blocks. U–Pb isotopic dating of zircon in the Brusque Complex of the northern Dom Feliciano Belt, Brazil, provides new constraints on the timing and sources of Neoproterozoic sedimentation along the eastern margin of the Luis Alves Craton. The minimum age of sedimentation is constrained by a U–Pb zircon age of 811 ± 6 Ma from a dyke cross-cutting the Brusque Complex. U–Pb detrital zircon analysis reveals two distinct groups: one with ages ca. 2.2–2.0 Ga consistent with erosion of the adjacent Luis Alves Craton, and another with ages ca. 2.1–1.8 and 1.6–1.0 Ga consistent with erosion of Paleoproterozoic to Mesoproterozoic igneous provinces and/or supracrustal sequences at the edge of the Congo Craton. The age distributions match with analogous rocks of the central Dom Feliciano Belt and the Kaoko Belt, and show similarities with the Gariep Belt, suggesting deposition in a system of coeval and spatially related paleobasins around the time of Rodinia breakup. The absence of Neoproterozoic detrital zircon close to the age of sedimentation suggests deposition in an intracontinental rift or passive margin. A third group contains a significant proportion of Neoproterozoic ca. 670–560 Ma zircon, suggesting similarities with the adjacent Itajaí Basin syn-orogenic foreland sedimentary rocks. This indicates that foreland basin sediments were partly tectonically interleaved with the pre-orogenic metasediments of the Brusque Complex during late-stage orogenic deformation. The findings support an intracontinental rifting model for the formation of the Kaoko–Dom Feliciano–Gariep basin system. The data further indicate that the Luis Alves Craton was in close proximity to the Congo Craton, and likely with the Nico Pérez Terrane and the Kalahari Craton, at the onset of Tonian rifting and the breakup of Rodinia. [ABSTRACT FROM AUTHOR]

• Granulite-facies metamorphic rocks discovered from the Diebusige Complex of the Alxa Block. • U–Pb age data reveal that timing of granulite-facies metamorphism is approximately 1850 Ma. • The Alxa Block may be the western extension of the Khondalite Belt during Palaeoproterozoic. The Diebusige Complex, the highest-grade metamorphic complex in the Alxa Block, can provide significant insights into the origin, formation, evolution, and tectonic affinity of the Alxa Block. Petrographic observations show that the mineral assemblage of (garnet) magnetite quartzite from the Diebusige Complex is magnetite + quartz + hypersthene + plagioclase ± clinopyroxene ± garnet. The metamorphic temperature (T) is constrained to 800–860 °C by the two-pyroxene geothermometer, corresponding to granulite-facies metamorphism. Geochronological studies involving cathodoluminescence (CL) images, LA-ICP-MS U-Pb dating, and trace element analyses of zircons show that the time of granulite-facies metamorphism was approximately 1850 Ma. Combined with the corresponding published data, this paper suggests that the metamorphic basement rocks of the Alxa Block record Neoarchaean-early Palaeoproterozoic magmatic-metamorphic and late Palaeoproterozoic granulite-facies metamorphic events, thereby indicating the affinity between the Alxa Block and the Khondalite Belt (KB). [ABSTRACT FROM AUTHOR]

• Clarifies the naming scheme of the Adelaide Superbasin. • Comprehensive detrital zircon database for the Neoproterozoic of the Adelaide Superbasin. • Publishes ∼3,500 new detrital zircon analyses for the Adelaide Superbasin. • Comprehensive review of the geochronology and provenance of the Neoproterozoic Adelaide Superbasin providing an updated basin evolution model within the context of detrital zircon provenance. • Provides an updated stratigraphic correlation for the Neoproterozoic formations within the Adelaide Superbasin. The Adelaide Superbasin (Adelaide Rift Complex, Stuart Shelf, Torrens Hinge Zone, Coombalarnie Platform, and Cambrian Stansbury and Arrowie Basins) is a vast sedimentary basin in southern Australia that initiated due to the break-up of central Rodinia and, evolved into the Australian passive margin on edge of the Pacific Basin. Rocks within it contain evidence for the evolving earth system through the Neoproterozoic, including type sections of the Ediacaran fauna, Sturtian and Marinoan glaciations, and the GSSP for the base of the Ediacaran period. Much research over the last century has unravelled the lithostratigraphy and sedimentology of the basin. Despite this, the rocks are poorly dated, and their sedimentary provenance and link with tectonic geography is poorly known. This poor chronology hampers global and local efforts to gain a detailed understanding and chronological framework of the interplay between tectonics and momentous changes to the earth system during this time. This paper presents a comprehensive database of detrital zircon geochronology and review of geochronology for the Neoproterozoic of the Adelaide Superbasin, highlighting the stratigraphic, and spatial locations of available data. In the north of the basin, zircons were sourced locally in the initial stages of rifting, ca. 830 Ma—from the adjacent Gawler Craton and Curnamona Province. During the late Tonian, detritus was transported along graben from the north-west, from the Musgrave Orogen, as the rift basin developed during the opening of the nascent Pacific Ocean. Cryogenian icesheets punctuate the detrital record with an ephemeral return to more localised rift shoulder sources. In the Ediacaran, there is an increasing influence of younger (<740 Ma) detrital zircon from an enigmatic source that we interpret to be from southern (i.e. Antarctic) sources, with a corresponding shift in the late Mesoproterozoic age peaks, from ca. 1180 Ma to ca. 1090 Ma, and corresponding decrease in older, ca. 1600 Ma, detritus. These changes in sediment source reflect the changing tectonic geography and large-scale environmental influence of the Cryogenian glaciations as the basin evolved from a local rift, to a larger rift basin and finally to a continental margin, with sedimentary input becoming increasingly restricted over time. [ABSTRACT FROM AUTHOR]

• Early Neoproterozoic magmatic arc may exist in the interior of the Yangtze Block. • The Xiaoxikou metasedimentary rocks of the Miaowan Complex were deposited in a fore-arc setting. • The ca 850 Ma leucocratic veins intruding the Xiaoxikou metasedimentary rocks were formed in a post-tectonic setting. • The construction of the current unified Yangtze Block most likely occurred between 900 and 860 Ma. The present Yangtze Block was proposed to be formed as a unified block in the Mesoproterozoic-Neoproterozoic transition, but the detailed timing and process are poorly constrained. Here we report integrated in situ U–Pb and Hf–O isotopic analyses of detrital zircons from the Xiaoxikou metamorphosed sedimentary rocks of the Miaowan Complex in the Yangtze Block, as well as U–Th–Pb and Nd–O isotopic analyses of magmatic monazites from an undeformed and unmetamorphosed leucocratic vein intruding these metasedimentary rocks. U–Pb dating results for detrital zircons from the metasedimentary rocks display two main age peaks at ca 970 and 900 Ma. The 970 Ma zircons are dominantly characterized by mantle-like δ18O zir values (4.5–5.8‰) and highly depleted ε Hf (t) values (+5 to + 14). The 900 Ma zircons mostly have O and Hf isotopic features similar to the 970 Ma zircons, except relative small proportion of grains with high δ18O values (6.0–9.2‰) and variable ε Hf (t) values (–33 to + 7). Monazites from the vein are dated at ca 850 Ma and have uniform δ18O values (5.4–6.6‰), but significantly enriched ε Nd (t) values (–14.5 to –12.6). Based on the new isotopic results and immature lithology, the Xiaoxikou metasedimentary rocks are interpreted to be deposited between 900 and 850 Ma in a fore-arc basin, and clastic materials derived from ca 970–900 Ma arc rocks were related to the northward subduction (present-day coordinates) of the Miaowan oceanic plate. The 850 Ma leucocratic vein shows geological and isotopic characteristics consistent with local 860–840 Ma post-tectonic granitic plutons, and may represent a fractionated product of local coeval granitic magmas. We propose that the closure of the Miaowan oceanic basin and formation of the current unified Yangtze Block occurred between 900 and 860 Ma, i.e., later than the deposition of the fore-arc metasedimentary rocks while earlier than the emplacement of the post-tectonic plutons. [ABSTRACT FROM AUTHOR]

• 270 new Hf in zircon analyses from the Siberian platform. • 800 U-Pb-Hf zircon analyses characterize the buried crust of the Siberian craton. • 4 existing models of basement structure are tested against the most recent data. New and compiled U-Pb-Hf detrital zircon data from provincial Meso- to Neoproterozoic sedimentary basins characterize the buried crust of the Siberian cratonic basement. Along the northwestern Siberian cratonic margin (Turukhansk uplift, Yenisei Ridge) the basins accumulated predominantly 2.6–2.5 Ga zircons with εHf (T) values of +3 to −7, and 1.9–1.85 Ga zircons, characterized by εHf (T) values of −10 to +10. In the southwestern part of the craton (Prisayan uplift), similar 1.9–1.85 Ga and older Archean zircons are common, whereas in the eastern part older Paleoproterozoic zircons of 2.15–1.95 Ga with minimum εHf (T) values of −25 are widespread. The unique detrital age spectra for various parts of the craton provide a basis for unravelling the age of buried domains of the Siberian craton. A correlation of isotopic records from different domains, combined with geological evidence, may suggest that the craton consists of (1) the Archean unit, younging toward the present N-W direction and (2) three N-S-trending Paleoproterozoic collisional belts, extending along its western (the Angara belt) and eastern (the Hapschan belt) margins, and in the middle of the craton (the Magan belt). The proposed structural and isotopic domains of the Siberian craton compare well with those of northern Laurentia, providing a new evidence for the two cratons were connected within the Nuna supercontinent. [ABSTRACT FROM AUTHOR]

• Spatial transition of 3 groups of Mesoarchean TTGs in Southern Marginal Zone (SMZ) • ~3.13 Ga low-pressure TTGs occur towards the northwest. • ~3.12–2.98 Ga medium-pressure TTGs dominate the central portion. • ~2.92 Ga high-pressure TTGs associated with ~2.85 Ga sanukitoid in the southeast. • SMZ along northeastern Kaapvaal Craton is an exotic terrane, part of Pilbara Craton. High-grade terranes along Archean cratonic margins either represent remobilized equivalents of the adjacent low-grade domain or an exotic entity which accreted to the developing craton. This study addresses this debate for the Southern Marginal Zone high-grade terrane along the northeastern margin of the Kaapvaal Craton. The Hout River shear zone separates the high-grade terrane from the adjacent low-grade Pietersburg block of the Kaapvaal Craton. Tonalite-trondhjemites of the Baviaanskloof gneiss unit constitute the dominant rock in the Southern Marginal Zone. Both pyroxene-bearing and pyroxene-absent variants occur. Locally, the granitoids are affected by anatectic and metasomatic overprints. Magmatic textures are better preserved in the massive granitoids. U-Pb zircon analyses of two orthopyroxene-bearing granitoids gave Mesoarchean crystallization ages [3088 ± 11 Ma (massive), 3121 ± 9 Ma (banded)]. However, overprint ages differ, with 2706 + 50/−34 Ma from the massive variety, and 1925 ± 19 Ma, 1976 ± 11 Ma from the banded variety. The syn -tectonic ~2.71 Ga is interpreted as metamorphic overprint age, while the post-tectonic ~2 Ga represent age of local overprint. Available geochemical data on the Baviaanskloof granitoids are similar to Archean TTGs. A possible spatial-temporal transition from ~3.13 Ga low-pressure through ~3.12–2.98 Ga medium-pressure to ~2.92 Ga high-pressure TTG is delineated from the northwest towards the southeastern Southern Marginal Zone. This trend is compatible with the southward directed polarity of accretion events recognised in the adjacent low-grade Pietersburg block. We argue that the northeastern margin of the Kaapvaal Craton, north of the Hout River shear zone, is an exotic terrane because 1) the Baviaanskloof granitoid event (~3.1–2.9 Ga with peak at ~3.1 Ga) is older than the accretion episodes (~2.97–2.92 Ga with peak at ~2.95 Ga, and ~2.87–2.84 Ga with peak at ~2.86 Ga) in the adjacent Pietersburg block, 2) the younger ~2.86 Ga event occurs closer to the Hout River shear zone, while the older ~2.95 Ga event was away from it, and 3) contemporaneous (~3.1–3.0 Ga) detrital zircons are absent in greenstone belts of the Pietersburg block that are proximal to the Hout River shear zone. Possible connection to rocks of similar age from the Pilbara Craton as part of the Vaalbara supercraton is explored. [ABSTRACT FROM AUTHOR]

South China is the largest block of Rodinia in southeastern Asia. It consists of the Yangtze and Cathaysia blocks, separated by the Jiangshan-Shaoxing-Pingxiang Fault. Most studies suggest that the two blocks were amalgamated in the early Neoproterozoic, and the middle Neoproterozoic vocano-sedimentary sequences on both blocks were deposited in a post-collisional rift basin (the Nanhua rift basin). Here, we conducted a geochemical and geochronological study of a turbidite sequence at the western margin of the Cathaysia Block that was previously considered to have been deposited in the Nanhua rift basin. The sedimentary rocks are characterized by bathypelagic to bathyal facies. They are composed of siliciclastic sedimentary rocks interlayered with tuffaceous materials and have geochemical compositions between felsic to intermediate arc igneous rocks. Abundant euhedral detrital zircons define a major age peak at ca. 790–770 Ma, indicating that the detrital grains were derived mostly from locally distributed syn-sedimentary middle Neoproterozoic arc igneous rocks. Predominance of zircons with ages close to the time of deposition and the whole-rock trace element compositions of the turbidite sequence also imply a convergent plate margin setting for the turbidite. The Hf isotopic compositions of the Neoproterozoic detrital zircons suggest that their provenance consisted of largely reworked crustal materials, inconsistent with a potential interpretation that similarly aged igneous rocks in the Jiangnan Orogen were the provenance. These lines of evidence, combined with other available data, suggest that the western margin of the Cathaysia Block (the West Cathaysia terrane) bears more similarities to the western and northern margins of the Yangtze Block and northern India and formed part of a Neoproterozoic subduction-accretion system located along the margin of Rodinia. We suggest that early Paleozoic strike-slip movement along the Jiangshan-Shaoxing-Pingxiang Fault played a significant role in shaping the current tectonic framework of South China by bringing the West Cathaysia terrane to its present position with respect to the Yangtze Block. [ABSTRACT FROM AUTHOR]

• Pur-Banera, a supracrustal sequence near Bhilwara, Aravalli Craton. • Structural mapping and zircon–monazite geochronology. • Complementary age records from zircons and monazites. • Magmatism at 3.2, 2.5, 1.8 Ga; Sedimentation at 1.6–1.3 Ga; Deformation at 1.3, 1.05, 0.85 Ga. • Relationship to assembly and breakup of supercontinent Rodinia. The Banded Gneissic Complex (BGC) of the Aravalli Craton in Rajasthan, northwestern India, forms the Archaean basement to the major, extensively studied, Proterozoic-age metasedimentary sequences of the Aravalli and Delhi Supergroups. However, the poorly documented deformation history of the basement and other supracrustal sequences, and insufficient geochronological work, limit a holistic understanding of the evolution of the Aravalli Craton. Here we present structural analysis and zircon and monazite geochronology of the relatively poorly studied Pur-Banera supracrustal belt in the Bhilwara region of south-central Rajasthan. The belt comprises paragneisses, carbonates, calc-gneisses, banded iron formations, garnetiferous schists, and amphibolites, deposited over Aravalli Supergroup rocks and locally also granite. A single detrital zircon core from the Pur-Banera paragneisses yields a 207Pb/206Pb age of 3159 ± 8 Ma (1σ), indicating a Mesoarchaean protolith. Magmatic zircon grains from the granite, here termed the Malola Granite, provide a 207Pb/206Pb crystallisation age of 2538 ± 11 Ma (95% confidence). The Pur-Banera supracrustals have experienced three phases of deformation, D 1 –D 3 , each of which produced a tectonic fabric. Zircon and monazite geochronology provides complementary ages. The detrital zircons, derived from both magmatic and metamorphic protoliths, provide ages of 3.2–1.7 Ga. Monazite ages of 1.3–0.8 Ga record multiple post-depositional tectonothermal events. Textural and compositional evidence and U–Th–total Pb monazite ages indicate that D 1 deformation occurred at ca. 1.30 Ga as a result of NW–SE-directed shortening, forming upright folds on the primary foliation that resulted in a penetrative fabric in the gneisses and schists. Subsequent NNE–SSW-directed deformation (D 2) between 1.13 and 1.05 Ga produced WNW–ESE-trending vertical folds in the gneisses and crenulations in the schists. Asymmetrical folds developed due to N–S dextral shearing at 0.85–0.80 Ga constitute the last phase of deformation (D 3). The Pur-Banera supracrustal rocks probably represent a rift-fill sequence, of Mesoproterozoic age (thus temporally equivalent to the Delhi Supergroup), deposited on an Archaean and Palaeoproterozoic basement, and repeatedly reworked during 1.30–0.80 Ga. [ABSTRACT FROM AUTHOR]

• New identified age of 2482 Ma was dated from the Wutai Complex. • The complexity of ∼2.5 Ga crustal growth can be recognized by Hf-isotope. • New Neoarchean-Paleoproterozoic two-step tectonic evolution model is established. The Wutai granite-greenstone belt, which formed in the Neoarchean-Paleoproterozoic, with the adjoining high-grade metamorphic Hengshan-Fuping region, record important transitions in crustal and tectonic evolution, although these evolutionary processes have still been in dispute. In this study, new U–Pb and Lu–Hf LA-ICP-MS zircon analyses were obtained from eight metamorphosed magmatic rocks in the Wutai-Hengshan-Fuping area in North China Craton (NCC). The results reveal that most of Wutai granitoids yield emplacement ages of 2.56–2.52 Ga, with corresponding ε Hf(t2) of +4.7 to +8.3. The tonalitic gneiss from Dongshandi intrusion, however, gives a new age of 2482 Ma and ε Hf(t2) of +2.5 to +4.6, which are similar with Yixingzhai Pluton marked by ages of 2501–2499 Ma and ε Hf(t2) of +3.2 to +4.4. Also, ∼2.7 Ga and ∼2.5 Ga continental crust generation are further revealed. But ∼2.5 Ga crustal growth is more complicated due to the involvement of old crustal components, which can be identified by variable ε Hf(t2) values ranging from −1.8 to +7.5. Thus, based on the distinctions of Hf isotopes, compositional and spatial features, two consecutive groups of 2.56–2.52 Ga and 2.52–2.48 Ga are recognized and a two-step tectonic evolution model for the Wutai-Hengshan-Fuping area is proposed. During 2.56–2.52 Ga, intra-oceanic subduction led to the formation of Wutai oceanic island arc, accompanied mainly by the development of Wutai granitoids (ε Hf(t2) of +4.7 to +8.3) and coeval volcanics (predominant arc-tholeiitic chemical affinity), corresponding to the juvenile crustal growth. Between 2.52 Ga and 2.48 Ga, with intervening oceanic crust between intra-oceanic arc and continent consumed, the Wutai intra-oceanic arc then collided and was obducted onto the western edge of the Hengshan-Fuping continental block. Large amounts of TTG gneisses produced in both the Wutai and Hengshan-Fuping (ε Hf(t) of −1.8 to +7.5), along with calc-alkaline volcanism in Wutai, possibly in response to the thickening through arc accretion and commencing the continental arc. This proposed two-step tectonic evolution model, combined with a late Neoarchean (2.6–2.5 Ga) intra-oceanic arc system along the northwestern of the Eastern Block (EB), probably provides a better explanation for the fundamental geodynamic mechanism for continental arc development at the Proterozoic dawn. [ABSTRACT FROM AUTHOR]