Precambrian Research最新文献

{"title":"Discrete Paleoproterozoic and Cretaceous mineralization events at the Liyuan gold deposit, central North China Craton","authors":"Ying Ma,&nbsp;Shao-Yong Jiang","doi":"10.1016/j.precamres.2025.107812","DOIUrl":"10.1016/j.precamres.2025.107812","url":null,"abstract":"<div><div>Accurate dating of Precambrian gold deposits is challenging due to the lack of suitable mineral chronometers. The North China Craton (NCC) is recognized as one of the world’s largest gold-producing regions; however, Precambrian-aged gold deposits within the NCC are relatively rare. This study aims to determine the formation age and evolutionary history of the Liyuan gold deposit (5 t Au), which is situated within high-grade metamorphic rocks of the Trans-North China Orogen. We employed U-Pb dating of hydrothermal apatite and rutile, as well as trace element analysis of texturally distinct pyrite. Two distinct stages of gold mineralization were identified. Stage I is characterized by the presence of disseminated pyrite that predominantly associated with lattice-bound gold. In contrast, stage II is marked by quartz-sulfide vein-style mineralization with visible gold and gold microinclusions within pyrite. Pyrite from Stage I (Py1) exhibits elevated As concentrations, whereas pyrite from stage II (Py2 and Py3) is distinguished by high levels of Te and Pb. Hydrothermal apatite intergrown with auriferous Py1 yielded U-Pb ages of 1895 ± 19 Ma and 1836 ± 28 Ma, which correspond to the deformation and metamorphism of the Trans-North China Orogen. The presence of positive Eu anomalies in the hydrothermal apatite suggests that it crystallized from a relatively oxidized fluid. The mechanism for the formation of hydrothermal rutile associated with the vein mineralization of stage II, is attributed to the alteration of biotite. Hydrothermal rutile was dated to 128.0 ± 6.4 Ma, which aligns with the Early Cretaceous granitic magmatism in the region. The Liyuan gold deposit was formed as a result of two distinct hydrothermal events occurring during the Paleoproterozoic and Early Cretaceous periods, respectively. This conclusion is supported by comprehensive field, textural, mineralogical, and geochronological analyses. The recently identified Paleoproterozoic orogenic gold mineralization event, which coincided with orogenic deformation and regional metamorphism during the collision between the Western and Eastern Blocks, presents new prospects for gold exploration in the well-endowed NCC. Furthermore, our study highlights the potential of apatite U-Pb dating as a reliable geochronological tool for investigating Precambrian gold deposits in other regions.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"424 ","pages":"Article 107812"},"PeriodicalIF":3.2,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144090204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis and tectonic implication of the Neoproterozoic Shuimo alkaline-carbonatite complex from Northwestern margin of the Yangtze Block (China)","authors":"Bin Lin ,&nbsp;Lian-Xun Wang ,&nbsp;Yu-Fang Zhong ,&nbsp;Xiao-Bing Qi ,&nbsp;Xue-Wei Fu ,&nbsp;Chang-Qian Ma","doi":"10.1016/j.precamres.2025.107813","DOIUrl":"10.1016/j.precamres.2025.107813","url":null,"abstract":"<div><div>To investigate the petrogenesis of the alkaline-carbonatite complex and the Neoproterozoic tectonic evolution for the northwestern margin of the Yangtze Block, we conducted a combined study of petrology, LA-ICP-MS zircon U-Pb geochronology, mineral chemistry, whole-rock geochemistry and Sr-Nd-C-O isotopes on the Shuimo alkaline-carbonatite complex in the area. The complex consists of ultrabasic alkaline rocks (jacupirangite and ijolite), syenites (aegirine-augite syenite and biotite syenite), and igneous carbonatites. Zircon U-Pb weighted mean age of the ijolite is 855 ± 4 Ma, consistent with previous studies that report ages of 860 ± 5 and 869 ± 4 Ma for syenites, indicating that the Shuimo alkaline magmatic activity occurred at approximately 860 Ma. The Shuimo alkaline rocks show relative enrichment in light rare earth elements (LREEs) and large ion lithophile elements (LILEs) while being depleted in high field strength elements (HFSEs). The alkaline rocks and carbonatites have similar Sr-Nd isotopes (I_Sr = 0.7045–0.7056 and εNd(t) = 0.28–4.97, I_Sr = 0.7042–0.7044 and εNd(t) = 1.07–2.55, respectively), indicating a common enriched lithospheric mantle source. Geochemical characteristics of minerals and whole rocks suggest that the Shuimo alkaline rocks originated from a nephelinitic alkaline magma formed by low-degree partial melting of garnet-bearing spinel lherzolite in the lithospheric mantle. The primary magma underwent fractionation of clinopyroxene during its early stage, resulting in gradual formation of jacupirangite and ijolite. In contrast, syenite formation involves crustal assimilation and fractional crystallization of the parent magma. Carbonatites are genetically associated with ultrabasic alkaline rocks and underwent fractional crystallization and liquid immiscibility during their formation. Tectonically, the Shuimo alkaline-carbonatite complex was formed in a continental back-arc extensional setting, where the mantle was metasomatized by slab-derived fluids, leading to carbonation and triggering partial melting. The results support the plate-subduction model for the northwestern margin of the Yangtze Block during the Neoproterozoic period and suggest that early back-arc extension occurred during the subduction. We propose a model for the formation of alkaline-carbonatite complexes in subduction-related extensional settings, which involves enriched mantle metasomatized by slab-derived fluids, fractional crystallization and crustal contamination of alkaline rocks, immiscible separation of carbonatites from evolved silica-undersaturated alkaline rocks, and late-stage fluid metasomatism that modifies the carbonatites.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"424 ","pages":"Article 107813"},"PeriodicalIF":3.2,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detrital zircon U-Pb geochronology of Ediacaran siliciclastic carbonate rocks in eastern South China: Insights into the Precambrian assembly of the Yangtze and Cathaysia blocks","authors":"Fengqi Zhang ,&nbsp;Jinjun Zhou ,&nbsp;Yildirim Dilek ,&nbsp;Kongyang Zhu ,&nbsp;Hongxiang Wu ,&nbsp;Dahai Sun ,&nbsp;Hongdan Deng ,&nbsp;Yunhao Sun ,&nbsp;Hanlin Chen ,&nbsp;Shufeng Yang","doi":"10.1016/j.precamres.2025.107814","DOIUrl":"10.1016/j.precamres.2025.107814","url":null,"abstract":"<div><div>The Cathaysia block, a composite terrane comprising West and East Cathaysia along the East Asian continental margin, forms a critical constituent of the South China block. Despite its tectonic significance, the timing of the Cathaysia–Yangtze amalgamation remains contentious, with proposed ages spanning from the Precambrian to the Mesozoic. We present integrated sedimentological and geochronological constraints derived from Ediacaran carbonate sequences in the Yuhang section of the southeastern Yangtze craton. Systematic analyses that combine sedimentary petrology with detrital zircon U-Pb-Hf isotopes reveal the following: 1) clastic components (30–45 % by volume) dominated by quartz exhibit a mixed siliciclastic carbonate rocks; 2) detrital zircon populations yield predominant Paleoproterozoic ages (2.0–1.75 Ga), showing remarkable similarities to the Precambrian basement of East Cathaysia, particularly through a characteristic age peak of 1.83–1.81 Ga; 3) Hf isotopic compositions demonstrate crustal residence ages that are indistinguishable from those of East Cathaysia sources. These convergent lines of evidence establish East Cathaysia as the primary sediment source for the southeastern Yangtze Ediacaran deposits. Consequently, we propose that the final amalgamation of the composite Cathaysia block with the Yangtze craton occurred during Precambrian crustal stabilization, fundamentally revising previous models that advocated for Phanerozoic accretion.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"424 ","pages":"Article 107814"},"PeriodicalIF":3.2,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144068365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution and innovation of the metazoan burrowing behaviour from Ediacaran-Cambrian transition, eastern Yunnan","authors":"Da Li ,&nbsp;Man Li ,&nbsp;Yongan Qi ,&nbsp;Guochun Zhao ,&nbsp;Jian Fu ,&nbsp;Fuqiang Guo ,&nbsp;Chengjun Zhang ,&nbsp;Jianyu Guan ,&nbsp;Shishan Zhang","doi":"10.1016/j.precamres.2025.107796","DOIUrl":"10.1016/j.precamres.2025.107796","url":null,"abstract":"<div><div>The Precambrian–Cambrian transition represents a pivotal interval in Earth’s evolutionary history, marked by the demise of Ediacaran biota and the subsequent radiation of bilaterian organisms during the Cambrian Explosion. This study presents an integrated ichnological and sedimentological analysis of trace fossils across the Precambrian–Cambrian boundary interval in eastern Yunnan, South China, with the aim of reconstructing paleoecological dynamics and behavioral evolution during this critical transitional phase.Ichnotaxonomic diversity, architectural complexity, and tiering structure reveal a progressive intensification of metazoan–substrate interactions through the late Ediacaran. Trace fossils from this interval are predominantly horizontal and exhibit morphologies consistent with undermat-mining behaviors, indicating that benthic organisms were largely restricted to the mat-substrate interface. However, rare but distinct vertical burrows suggest the incipient development of exploratory and infaunal lifestyles.With the onset of the Cambrian, there is a notable increase in ichnodiversity, behavioral complexity, and substrate utilization, reflecting enhanced metazoan motility and ecological specialization. This period coincides with a shift from microbial-mat-dominated substrates to mixed-layer systems, driven by increasing bioturbation intensity. By Cambrian Stage 2, widespread bioturbation led to the progressive disruption of microbial mats and facilitated more extensive exploitation of three-dimensional ecological space.Benthic communities expanded their spatial occupation from surficial and semi-infaunal tiers into deeper substrate horizons, promoting greater ecological stratification and trophic complexity. These paleoecological transformations culminated in the replacement of Neoproterozoic-style matgrounds by Phanerozoic-type mix-grounds, representing a fundamental reorganization of marine ecosystems and a major milestone in the early ecosystem evolution of benthic communities.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107796"},"PeriodicalIF":3.2,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Debunking the myth of a single Iron Ore Group in the Singhbhum Craton, India","authors":"Jaganmoy Jodder ,&nbsp;Axel Hofmann ,&nbsp;Marlina A. Elburg ,&nbsp;Rebeun Ngobeli ,&nbsp;Trond H. Torsvik","doi":"10.1016/j.precamres.2025.107800","DOIUrl":"10.1016/j.precamres.2025.107800","url":null,"abstract":"<div><div>Archaean cratonic cover successions with well-preserved banded iron-formations (BIF) and shales provide a crucial window into early Earth surface processes. Here, we report on the intra-cratonic volcano-sedimentary sequences of the Koira and Simlipal groups of the Singhbhum Craton of India, regarded by some to be equivalent of Palaeoarchaean BIF-bearing greenstone successions collectively referred to as Iron Ore Group. However, field relationships and precise LA-Q-ICP-MS U-Pb detrital zircon ages from basal siliciclastic units of the Koira Group, non-conformably overlying Palaeo- to Mesoarchaean granitoid-greenstone basement, record a maximum depositional age of ca. 2.86 Ga. Sandstone intercalated with shale and banded iron formation of the Koira Group yields a maximum depositional age of ca. 2.68 Ga, placing the deposition of the iron formation and correlative units firmly into the Neoarchaean. The data therefore call for separate BIF–bearing sequences of Palaeoarchaean and Neoarchaean age, thus debunking the persistent myth of a single Iron Ore Group in the Singhbhum Craton of India. It further underscores similarities in the evolution of the Kaapvaal, Pilbara and Singhbhum cratons, which emerged in Mesoarchaean times to accommodate shallow-marine strata and sub-aerial flood basalts in an intra-continental setting.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107800"},"PeriodicalIF":3.2,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of Nb, Ta, and Cs in Precambrian low-grade metamorphic basement rocks in South China: Mineralogical characterization and petrogenetic significance","authors":"Yuli Yuan,&nbsp;He Zhang,&nbsp;Yuanfeng Cai,&nbsp;Xi Zhao,&nbsp;Yuguan Pan,&nbsp;Jinhai Yu","doi":"10.1016/j.precamres.2025.107794","DOIUrl":"10.1016/j.precamres.2025.107794","url":null,"abstract":"<div><div>This paper describes the occurrence of Nb, Ta, and Cs in Precambrian low-grade metamorphic basement rocks in South China. The occurrence of Nb, Ta, and Cs in slates was investigated using a combination of chemical and structural characterization techniques (i.e., trace element geochemistry, electron probe microanalysis, scanning electron microscopy, X-ray diffraction, and transmission electron microscopy). Cs⁺ is hosted in either Cs-bearing sericite. Nb⁵⁺ and Ta⁵⁺ occur mainly in the octahedral sites of sericite and Fe-chlorite. During prograde metamorphism, the Cs⁺, Nb⁵⁺, and Ta⁵⁺ ions that were originally adsorbed on the surfaces of kaolinite and montmorillonite were incorporated into the lattice of phyllosilicate minerals such as sericite and Fe-chlorite. Crystal-chemical calculations reveal a clear compositional trend from Al- to Fe-chlorite with increasing temperature, along with an increase in Nb contents. Our results provide direct mineralogical evidence for the pre-enrichment of ore-forming elements in the basement rocks of South China, as well as in similar settings worldwide; e.g., the Northern Cape and southern Ghana Li-Cs-Ta deposits in Paleoproterozoic shales of the Wa-Lawra Belt. The Nb- and Ta-bearing Fe-chlorite and Cs-bearing sericite are examples of new occurrences of critical metals in low-grade metamorphic rocks.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107794"},"PeriodicalIF":3.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting early Neoproterozoic mafic sills in the North China Craton","authors":"Zhongwu Lan ,&nbsp;Zhensheng Li ,&nbsp;Sandra Kamo ,&nbsp;Peng Peng ,&nbsp;Mingguo Zhai","doi":"10.1016/j.precamres.2025.107788","DOIUrl":"10.1016/j.precamres.2025.107788","url":null,"abstract":"<div><div>Neoproterozoic Large Igneous Provinces (LIPs) continue to receive worldwide attention due to their genetic links with supercontinent dispersal and use in paleocontinental reconstructions, formation of ore deposits, climate shifts, and biological extinctions. However, their utility is hampered by a lack of high precision geochronology. Here we present a new U-Pb ID-TIMS baddeleyite age for a Neoproterozoic mafic sill intrusion in the North China Craton (NCC). A mafic intrusion within the Huaibei/Huaihe Group of Xuhuai Basin, previously dated between 915 Ma and 900 Ma (U-Pb zircon/baddeleyite LA-ICP-MS) gives a baddeleyite age of 906.5 ± 1.1 Ma. Given the wide occurrence of 915–900 Ma mafic intrusions dated previously, this new age potentially suggests a widespread ca. 907 Ma mafic intrusive event across NCC. Furthermore, this baddeleyite age constrained the Huaibei/Huaihe Group to have deposited in an age span of 1121–907 Ma. Apatite grains from the mafic sills have also been dated by U-Pb LA-ICP-MS, which produced dates that range from 984 ± 64 Ma to 930 ± 57 Ma, with errors similar to previous zircon/baddeleyite U-Pb LA-ICP-MS dates, indicating the feasibility of apatite U-Pb geochronology to constrain the timing of mafic intrusions. REE distribution patterns coupled with the Sr/Y-LREE discrimination plots demonstrate a primary origin for the dated apatite grains. Apatite crystallized from mafic magmas following earlier crystallization of feldspar that incorporated significant amounts of Eu.</div><div>Recalculation of nearly 600 radio-isotopic data points on Neoproterozoic mafic intrusions in the NCC yield three age peaks at ca. 940 Ma, ca. 915 Ma and ca. 885 Ma, respectively. The major age peak at ca. 915 Ma is broadly consistent with our U-Pb ID-TIMS baddeleyite age that is suggestive of the main episode of mafic intrusion. Further high precision U-Pb ID-TIMS geochronology is necessary to precisely constrain the timing of the ca. 940 Ma and ca. 885 Ma mafic intrusions.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107788"},"PeriodicalIF":3.2,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The southwesternmost piece of the Grenville Orogen in Laurentia – New U-Pb and Sm-Nd ages, and P-T estimates from the Sierra del Cuervo, Chihuahua, Mexico","authors":"Bodo Weber ,&nbsp;C. Nayeli Chacón-Olivas ,&nbsp;M. Daniela Tazzo-Rangel ,&nbsp;Miguel Franco-Rubio ,&nbsp;Reneé González-Guzmán ,&nbsp;Felix E.D. Kaufmann ,&nbsp;Dirk Frei","doi":"10.1016/j.precamres.2025.107793","DOIUrl":"10.1016/j.precamres.2025.107793","url":null,"abstract":"<div><div>This paper elucidates the origin and tectonic setting of Mesoproterozoic metaigneous rocks of the Sierra de Cuervo, Chihuahua, Mexico, providing new evidence for the southwestern extension of the Grenville Orogeny in North America. Several geochronological approaches were used, including U-Pb zircon dating by LA-ICP-MS and the Sm-Nd isochron technique, using ID-TIMS. Igneous zircon domains reveal crystallization ages for felsic igneous protoliths ranging from ∼ 1.38 Ga to ∼ 1.33 Ga, with ∼ 1.42 b.yr. old inherited zircon. Whole-rock Sm-Nd isotopic data define an isochron at 1.52 ± 0.03 Ga, suggesting crustal growth during the early Mesoproterozoic. The timing of metamorphism is constrained by Sm-Nd leached garnet-whole-rock isochrons and by U-Pb zircon dates between ∼ 1.06 and ∼ 1.05 Ga. Metamorphic pressure and temperature conditions were estimated from a metamafic rock sample at 6.4 ± 1 kbar and 520 ± 20 °C using conventional geothermobarometry and pseudosection modeling. The results contextualize the Precambrian rocks of the Sierra del Cuervo with metamorphic rocks of the West Texas Uplift thrust over the Laurentian margin. We propose that this thrust represents a remnant of the unexposed Grenville Front and that the Chihuahua and West Texas metamorphic basement is characterized by contemporaneous magmatism and reworked from the Granite-Rhyolite Province of the North American midcontinent during the Grenville Orogeny, comparable to the low-medium pressure allochthonous Ottawan metamorphic belt of the Grenville Province in Canada.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107793"},"PeriodicalIF":3.2,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143912368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The lithosphere effective elastic thickness with its anisotropy of the North China Craton","authors":"Wen Shi ,&nbsp;Shi Chen ,&nbsp;Yongbo Li ,&nbsp;Yuhang Pan ,&nbsp;Lulu Jia ,&nbsp;Honglei Li ,&nbsp;Huili Guo","doi":"10.1016/j.precamres.2025.107798","DOIUrl":"10.1016/j.precamres.2025.107798","url":null,"abstract":"<div><div>The North China Craton (NCC) is one of the oldest cratons in the world. It is important to understand the mechanism of NCC destruction. The lithosphere effective elastic thickness (<span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span>) with its anisotropy can provide new insights into those mechanisms, as the spatial distribution patterns of <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> and its anisotropy serve as distinctive indicators of past tectonic processes that are difficult to characterize through conventional approaches. The <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> and load ratio (<span><math><mrow><mi>F</mi></mrow></math></span>) around the NCC region are estimated using a joint inversion method that integrated both admittance and coherence techniques. The <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> anisotropy is estimated using fan wavelet coherence method. The derived <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> and <span><math><mrow><mi>F</mi></mrow></math></span> are used to compute flexural isostatic anomalies (FIA) using the theoretical Bouguer admittance method. We find the <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span>, <span><math><mrow><mi>F</mi></mrow></math></span>, <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> anisotropy, and FIA vary a lot from east to west in the NCC area. The Ordos Basin in the western North China Craton (WNCC) has high <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span>, low <span><math><mrow><mi>F</mi></mrow></math></span>, and weak <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> anisotropy, suggesting that the lithosphere of Ordos Basin have high strength and in a state of stable. The Trans-North China Orogen (TNCO) is located in transition zone of <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span>, <span><math><mrow><mi>F</mi></mrow></math></span>, <span><math><mrow><msub><mi>T</mi><mi>e</mi></msub></mrow></math></span> anisotropy, and FIA, indicating that the TNCO could be the front of collision between Eurasia Plate and western Pacific Plate. The eastern North China Craton (ENCC) lithosphere has been largely modified by the deep tectonic activities due to the subduction of western Pacific Plate.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"423 ","pages":"Article 107798"},"PeriodicalIF":3.2,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143899368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neoproterozoic accretionary tectonics of the northern Yangtze Block: Constrains from the geochemistry and geochronology of the volcanic-sedimentary succession","authors":"Shuai He ,&nbsp;Yunpeng Dong ,&nbsp;Feifei Zhang ,&nbsp;Shengsi Sun ,&nbsp;Bo Hui ,&nbsp;Weidong He","doi":"10.1016/j.precamres.2025.107799","DOIUrl":"10.1016/j.precamres.2025.107799","url":null,"abstract":"<div><div>The unclear tectonic evolution of the northern margin of the Yangtze Block during the middle Neoproterozoic impedes our comprehensive understanding of the breakup of the supercontinent Rodinia. The Suixian volcanic-sedimentary group in the South Qinling Belt is crucial for elucidating this issue. This study presents a comprehensive investigation of volcanic rocks within the Suixian Group, utilizing zircon U-Pb geochronology and Hf isotope analysis, whole-rock major and trace element analysis, as well as Sr-Nd isotopic analysis. The geochemical characteristics indicate that the mafic volcanic rocks exhibit three distinct types. The first type resembles island arc basalts, enriched in large ion lithophile elements and depleted in high field strength elements, with positive ε_Nd(t) values, suggesting derivation from mantle metasomatized by subduction-related fluids. The second type displays high Nb values and geochemical characteristics akin to Nb-enriched basalts, possibly linked to slab window tectonics. The third type possesses an E-MORB-like trace element composition and positive ε_Nd(t) values, resembling basalts formed during back-arc extension. Felsic volcanic rocks from the Suixian Group yield zircon U-Pb ages of 747 ± 5 Ma, 743 ± 4 Ma, and 742 ± 5 Ma. These felsic rocks belong to the calc-alkaline to high-K calc-alkaline series and are characterized by enrichment in large ion lithophile elements and depletion in high field strength elements. Zircon Hf isotopic analyses reveal that the felsic rocks exhibit heterogeneous ε_Hf(t) values ranging from -9.2 to -1.0, indicating formation by partial melting of the lower crust triggered by mantle-derived magma. Combined with geological features of the Suixian Group and previous detrital zircon U-Pb geochronological studies, we infer that the formation of the Suixian Group can be attributed to a multistage process encompassing the subduction of oceanic slab in the early stage and subsequent back-arc extension, further confirming a sustained subduction-accretion tectonic setting along the northern margin of the Yangtze Block during the middle Neoproterozoic.</div></div>","PeriodicalId":49674,"journal":{"name":"Precambrian Research","volume":"422 ","pages":"Article 107799"},"PeriodicalIF":3.2,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}