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• Zircon ages reveal that the Helanshan shear zones developed at ca. 1904–1826 Ma. • Orogen-parallel shear zones in the Khondalite Belt occurred at ca. 1.90–1.82 Ga. • The Khondalite Belt suffered polyphase deformation (D 1 -D 3) at ca. 1.97–1.82 Ga. • The Khondalite Belt recorded a protracted (>100 Myr) orogeny in the Orosirian. The Khondalite Belt has been regarded as a Paleoproterozoic collisional orogen in the northwestern North China Craton, but the geochronological framework of polyphase deformation in the Khondalite Belt still remains unclear, particularly the timing of orogen-parallel ductile shearing. In this study, we conducted field-based structural analysis and LA-ICP-MS zircon U-Pb geochronology on the Helanshan ductile shear zones (HDSZ) in the Khondalite Belt. The results show that three pre-kinematic leucocratic dykes have been reworked by the shear zones and yielded magmatic zircon ages of 1934 ± 13 Ma, 1924 ± 5 Ma and 1920 ± 24 Ma. Two syn -kinematic leucocratic dykes appeared along the mylonitic foliations and were dated at 1887 ± 21 Ma and 1871 ± 28 Ma. A post-kinematic leucocratic dyke cut the mylonitic foliations and gave a crystallization age of 1816 ± 28 Ma. These emplacement ages of shear zone-related dykes constrain the development of the HDSZ at some time between ∼ 1920 Ma and ∼ 1816 Ma. Meanwhile, zircon overgrowth rims from three intrusions that suffered the shear deformation exhibited metamorphic ages of 1904 ± 11 Ma, 1840 ± 13 Ma and 1826 ± 31 Ma. Similar metamorphic ages of 1901 ± 7 Ma, 1888 ± 8 Ma and 1849 ± 29 Ma were also obtained from high-temperature felsic, pelitic and calcitic mylonites. These results further unravel that the HDSZ most likely developed at ca. 1904–1826 Ma. Additionally, we have summarized available deformation-related geochronological data in the Khondalite Belt, and proposed that this belt underwent three major phases of deformation (D 1 -D 3) in the Orosirian. D 1 mainly produced overturned to recumbent isoclinal folds F 1 , penetrative transposition foliations S 1 and mineral lineations L 1 at ca. 1.97–1.93 Ga. Subsequently, D 2 dominantly resulted in tight to open upright folds F 2 at ca. 1.93–1.90 Ga. Later, D 3 generated a series of NE- to E-trending orogen-parallel ductile shear zones at ca. 1.90–1.82 Ga. Together with multiple high-grade metamorphism and magmatism, the D 1 -D 3 deformation recorded a complex protracted orogeny (>100 Myr) in response to the collision between the Yinshan and Ordos blocks. [ABSTRACT FROM AUTHOR]

• This is the first discovery of Paleoproterozoic nepheline syenite in Trans-North China orogen. • The rock has experienced metamorphism at 1.87 Ga following its crystallization at 1.89 Ga. • It was derived from mafic continental crust under high-pressure condition. • It indicates continental subduction at 1.9 Ga during assembly of North Craton craton. Subduction of continent is known as a feature of modern plate tectonics, and it is still unclear whether such a process also occurred in the early Precambrian. Despite of ultra-high pressure metamorphism of terrestrial rocks as a proxy of continental subduction, magmatism produced during continental subduction is also a potential alternative. The North China craton is well-known for the occurrence of 1.9 Ga retrograde eclogite, which was likely originated from the subducting oceanic crust along the Trans-North China Orogen (TNCO). Here a nepheline syenite (the Aohu pluton), the first of the kind from the TNCO, is discovered in Yunzhong Mts. It comprises nepheline (∼20 vol%), albite (50–55 vol%), K-feldspar (5–10 vol%), biotite (∼10 vol%), and calcite (∼5 vol%), with minor accessory minerals. No associated mafic or silicic rocks are outcropped in the pluton. SHRIMP zircon U-Pb analyses yield a crystallization age of 1893 ± 13 Ma and a metamorphic overprinting of 1871 ± 17 Ma. The rocks have medium SiO 2 contents (51.9–58.9 wt%), low MgO (0.6–1.6 wt%) and Mg# (24–34), but high Al 2 O 3 (20.0–22.9 wt%) and extremely high K 2 O + Na 2 O contents (10.0–13.6 wt%; Na 2 O/K 2 O = 1.3–2.6). They are enriched in light rare earth elements (REEs) and large ion lithophile elements, but relatively depleted in heavy REEs and high field strengthen elements. They have extremely low compatible elements (e.g., Ni and Cr). They show high (87Sr/86Sr) i ratios (0.706–0.707) but low ε Nd (t) values (−5.3 to −6.0; Nd T 2DM = ca. 2.7 Ga). Their zircon in-situ ε Hf (t) values have a wide range (0 to −5.7; Hf T 2DM = 2.5–2.85 Ga). The absence of mafic component and the extremely low-Mg feature, as well as their trace element patterns and initial Sr-Nd isotopes being compatible with melts derived from the Archean mafic crustal enclaves in the region, support a continental crust origin for the Aohu nepheline syenite. Based on comparison and modeling, we suggest that its generation was most likely under ultra-high pressure condition. It is thus proposed that continental subduction (into the mantle) might have occurred in the TNCO during the Paleoproterozoic. [ABSTRACT FROM AUTHOR]

[Display omitted] • Summarized how big data can be applied in Precambrian research. • Conjoint analyses using big geochemical data reveal NCC formation and evolution. • Revealing magma cycle indicates NCC involved supercontinent cycle since Archean. • ML-based crust thickness reconstruction highlights arc subduction in NCC formation. • Spatio-temporal analyses suggest prolonged accretion in Precambrian NCC development. The enigmatic nature of the Precambrian era poses ongoing challenges for researchers seeking to uncover its secrets. With the exponential growth of scientific data, there exists a vast repository of information through which these mysteries can be explored. However, this data is often derived from fragmented investigations of geological phenomena within specific disciplinary domains and limited spatiotemporal boundaries, resulting in untapped potential for extracting undiscovered knowledge. To address this limitation, the field of big data science provides a foundation for multidisciplinary research on the geological evolution of the Precambrian. By harnessing the power of large-scale data integration and analysis, valuable insights into this pivotal era in Earth's history can be revealed. This paper offers a comprehensive overview of big data types in geoscience and elucidates common analysis methods. Through a case study focused on the North China Craton (NCC), we demonstrate the application of conjoint analysis to a dataset comprising rock and mineral geochemistry data. Employing local singularity analysis and wavelet analysis on zircon age frequency and Hf isotopic time series, we reveal a persistent long-term periodicity of 800–500 million years since 3.5 billion years ago. This finding indicates a co-evolution between the NCC and the global supercontinent cycle dating back to the Archean period. To investigate the formation of the NCC, we employ machine learning-based crustal thickness evolution reconstruction, which highlights arc formation during subduction as the primary factor, with regional mantle activities playing a secondary role in the convergence. Combining spatio-temporal evolution analysis of magmatic intensity and εHf(t) values, we infer that the development of the NCC primarily resulted from a prolonged process of accretion targeting the Eastern Block (the primary continent nuclei) through the incorporation of diverse arc massifs. This examination of the NCC serves as an example of how data collection, processing, and utilization can enhance our understanding of formational and evolutionary processes, signaling a paradigm shift in Precambrian research driven by the integration of big data. [ABSTRACT FROM AUTHOR]

• We identified a previously unknown ∼2.9 Ga magmatic event in Eastern Hebei, which may challenges the long-held view that granitic gneisses in Eastern Hebei Province, though diverse in composition, type and origin, were emplaced and crystallized in a rather short period of magmatic activity. We report the results of a comprehensive isotopic investigation of zircons from metamorphosed orthogneisses from Caochang village in the Zunhua Complex, Eastern Hebei, North China Craton (NCC). A detailed investigation of the internal structures of these zircons combined with SIMS U–Pb and ICP-MS Lu-Hf zircon analyses, as well as a whole-rock geochemical study, revealed a previously unknown ∼2.9 Ga magmatic event in Eastern Hebei. The identified Mesoarchean gneisses are mainly felsic gneisses and amphibolites. Amphibolites with positive εNd(t) values were derived from the depleted mantle, with some crustal contamination during ascent. Zircon Hf isotopes indicate that the high-silica gneisses originate from the high-temperature mixing of mafic magma derived from a depleted mantle source and the subsequent felsic magma derived from the melting of ancient crustal materials, with the subsequent high degree fractional crystallization of the parental magma. Some of the 2.9 Ga felsic gneisses may record an anatectic event at 2.5 Ga. The widespread ancient inherited and detrital zircons (>2.6 Ga) and the existence of Mesoarchean rocks imply a possible ancient continent in Eastern Hebei. It may also imply that the Mesoarchean era (especially at 2.9 Ga) represents another important magmatic event in the eastern block of the NCC. The identification of 2.9 Ga rocks indicates that the magmatic history of Eastern Hebei is far more complex than previously thought. [ABSTRACT FROM AUTHOR]

The North China Craton (NCC) is one of the oldest cratons in the world that preserves the records of many important geological events in the early evolution of the Earth. However, the early Precambrian tectonic evolution history of the NCC is still controversial. Here we report Paleoproterozoic leucogranites, garnet granites and granulites in the Fengzhen area that constitutes a junction between the Khondalite Belt and the Trans-North China Orogen (TNCO). The leucogranites have high SiO 2 content (75–85 wt%), and magmatic zircon U-Pb age of 2199 ± 3 Ma. Their zircons have slightly various εHf (t) values (−0.45 to 1.41) with T DM model ages of 2.5–2.6 Ga. The granites show strong LREE enrichment with La/Yb cn ratio of 12–176, and have high initial Nd isotope (ε Nd(t) = 3.5–4.5). Most of them display positive Eu anomaly, excluding fractional crystallization contribution on the high Si feature. The leucogranite was produced by melting of Late Archean felsic TTGs (tonalite–trondhjemite–granodiorite) and addition of juvenile crust. Magmatic zircons yield the garnet granite age of 2002 ± 3 Ma. The zircons show various εHf (t) values (−5.8 to 7.1) and T DM model ages (2.1–2.6 Ga). Low initial ε Nd(t) isotope value (−4.2 to −8.3) was determined in the granites. The granulites are high pressure metamorphic rocks with a peak pressure of 12.0 ± 0.8 kbar, and have similar metamorphic age of 1967 ± 10 Ma to the garnet granites. This indicates that the Fengzhen area underwent 2-Ga inter-continental orogeny, in which the melting of sedimentary rock formed the garnet granites. Similarly, sodic TTG melting to form K-rich leucogranites also needs high pressure. However, the leucogranite age is obviously older than the peak metamorphic timing of continent–continent collision. This implies that the Fengzhen area may have underwent arc-continental collision at 2.2 Ga. [ABSTRACT FROM AUTHOR]

There are different viewpoints on metamorphic and anatectic zircons recording ages of 2.45–2.48 Ga or even younger in some areas of the North China Craton where both late Neoarchean and late Paleoproterozoic tectono-thermal events are well developed. These are: 1) partial resetting of the U-Pb isotopic system in the late Neoarchean zircons, 2) metamorphism lasting from the late Neoarchean to the earliest Paleoproterozoic, and 3) earliest Paleoproterozoic metamorphism as separate different event. Western Shandong Province is an area where the late Neoarchean tectono-thermal event is widely developed but the late Paleoproterozoic event has not been identified. This provides an opportunity to understand the geological processes around the Archean-Proterozoic boundary. Based on a field study, we carried out SHRIMP U-Pb zircon dating on seventeen samples of ∼2.5 Ga old metamorphic and anatectic rocks, including tonalite, trondhjemite, granodiorite, gabbro, quartz diorite, granite and paragneiss with primary emplacement or depositional ages of 2.52–2.68 Ga. Anatectic zircons show some textural and compositional features: a) Homogenous or blurred oscillatory zoning, b) high U contents and low in Th/U ratios (commonly <0.3), c) rare idiomorphic morphologies, and d) commonly containing inherited (xenocrystic) cores. We conclude that the strong late Neoarchean event is widespread in western Shandong and is limited between ∼2.50 and 2.54 Ga. In contrast, apparent 2.45–2.48 Ga metamorphic zircon ages in some other areas of the North China Craton may be the result of overprinting and partial recrystallization of Neoarchean metamorphic zircons during the late Paleoproterozoic event. The Archaean rocks of western Shandong can be divided into three belts, namely Belts A, B and C from the northeast to the southwest. The difference between Belts A and B in ∼2.5 Ga metamorphic and anatectic intensity may indicate that the former was elevated to a higher crustal level compared with the latter at the end of the Neoarchean. [ABSTRACT FROM AUTHOR]

• Detrital zircon age spectra analyses suggest that the Quanji Group and the overlying Neoproterozoic rocks in the OLT may have different source provenances. • The Great Unconformity in the OLT and NCC consists of two or three discrete unconformities. • These unconformities may have been caused by multiple tectonic activities rather than a single, global synchronous one. The Great Unconformity that separates the early Cambrian sandstones from the Proterozoic metamorphosed sedimentary rocks has been recognized in many blocks on Earth. However, whether it represents a globally synchronous event or a composite of a series of diachronous events, and its formation mechanism remain largely unknown. In this study, we carry out detrital zircon U-Pb analyses for seven samples collected from the Paleoproterozoic Quanji Group and the overlying Neoproterozoic strata in the Olongbuluke terrane (OLT) of Northwest China. The results show that apart from age populations of ∼ 1.8–2.0 Ga and ∼ 2.2–2.5 Ga for all samples, additional ∼ 1.55–1.65 Ga age population occurs in sample from the Zhoujieshan Formation, and more scattered age populations ranging from ∼ 0.75 to ∼ 1.7 Ga are present in samples from the Heitupo and Hongtiegou formations. The ∼ 1.8–2.0 Ga and ∼ 2.2–2.5 Ga zircons correlate well with the magmatic and metamorphic events in the OLT basement, indicating their local provenances, while other zircons were possibly derived from the North China craton (NCC) or other adjacent blocks. Combined with published paleontological, stratigraphic, and geochronological data, the present study supports previous inference that the OLT had a close paleogeographic affinity to the NCC during late Paleoproterozoic to Neoproterozoic. New zircon U-Pb ages indicate that the Heitupo Formation was deposited later than ∼ 750 Ma, and the underlying Hongzaoshan Formation was deposited at ∼ 1.66 Ga, implying a huge break between them. Whereas the duration of the sedimentary break between the Heitupo Formation and the overlying Hongtiegou Formation is uncertain, biostratigraphic data suggest that a break of ∼ 30 Myr may exist between the late Ediacaran Zhoujieshan Formation and the overlying early Cambrian Xiaogaolu Group. The occurrences of these multiple unconformities in OLT are comparable to those in NCC, indicating that the Great Unconformity is represented by a series of lengthy denudations during the Proterozoic-early Cambrian in both the OLT and NCC, which may result from multiple tectonic activities in these two blocks. [ABSTRACT FROM AUTHOR]

• 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]

• 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]

• 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]