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The Palaeozoic tectonic evolution of the Western Kunlun Orogen plays an important role in deciphering the Tethyan tectonic evolution. This study provides new geochronology, geochemistry and Lu–Hf isotopic data of igneous rocks from the Omixia Complex in the eastern section of the northern Western Kunlun, as well as detrital zircon ages from turbidites and meta‐sediments north of it. From the Omixia Complex, the determined ages of five ultramafic–mafic rock samples are approximately 470, 456, 429, 401 and 382 Ma. Two samples of acidic rocks from the same complex yielded ages of approximately 438 and 378 Ma. One pegmatitic plagiogranite sample exhibits feature of accretionary arc granites, while other samples show geochemical characteristics of island arc tholeiite and E‐MORB. Additionally, four turbidite matrix and two limestone samples, with a major peak around ca. 480–500 Ma, have the youngest zircon ages ranging from ca. 481 to 387 Ma, paralleling the age range of igneous rocks in the ophiolitic mélange. The εHf(t) values of these samples reveal a broad spectrum of crustal and mantle processes. The youngest zircon ages of five meta‐sedimentary rock samples north of the Omixia Complex range from ca. 581 to 535 Ma, with peak ages concentrated around ca. 0.9–1.0 Ga. Their provenance characteristics differ from the turbidite matrix in the southern Omixia Complex and from the meta‐sediments in the northern Tiklik terrane with peak ages of ca. 0.8 Ga. A younger limestone sample yielded youngest zircon age of ca. 294 Ma, which is unconformably overlain the Omixia Complex and surrounding older rocks. Based on these new results, combined with previous data, we propose a new tectonic model for the eastern section of the northern Western Kunlun Orogen, suggesting a continuous evolution process of multi‐terrane subduction–accretion collage from the Early Ordovician to the Middle Devonian in the Paleo‐Tethys Ocean, which evolved into an Andean‐type active margin in the Early Permian, contributing to the substantial continental growth of the southern Tarim Craton. [ABSTRACT FROM AUTHOR]

We present new zircon U/Pb provenance data using laser ablation induced coupled plasma mass spectroscopy (LA‐ICP‐MS) for eight samples of mature quartz arenites and subarkosic sandstones of the Lower Ordovician Khabour Formation, northern Iraq, to establish their depositional age and provenance. The samples were collected from thin‐ to medium‐bedded sandstones along profiles of the Chalky Nasara and Ora sections. Most analysed detrital zircon analyses are concordant within 100 ± 10% and include a prevalence of Proterozoic over Archean ages. Collectively, the data can be divided into four main age groups: (a) Neoproterozoic ages, 570–1,000 Ma (58%); (b) Mesoproterozoic ages, 1,000–1,500 Ma (10%); (c) Palaeoproterozoic ages, 1,620–2,480 Ma (21%); and (d) Archean ages, 2,500–3,300 Ma (11%). The predominance of Cryogenian–Ediacaran ages (850–550 Ma) reflects major magmatic events associated with the assembly of northern Gondwana. The major age group at ~600 Ma likely represents the unroofing of late‐stage granitic rocks from the Arabian‐Nubian Shield. The lack of zircons younger than 490 Ma suggests that Lower Ordovician sandstones in northern Iraq were probably deposited on the distal shelf of the northern Gondwana passive margin and were not influenced by rifting and magmatism in northern Gondwana caused by the opening of Palaeo‐Tethys. Diagenetic xenotime overgrowths are common on detrital zircon grains, but radiometric dating of these was not possible. [ABSTRACT FROM AUTHOR]

The U–Pb and Lu–Hf isotopic research of detrital zircons was carried out in southern modern rivers of the South Tianshan (STS) orogenic belt to understand the accretionary processes and crustal evolution in this region. Detrital zircons from river sands yield two dominant age populations at 460–390 Ma and 310–260 Ma with several Precambrian age groups. Such age patterns imply that the significant magmatic events occurred during the Palaeozoic in the STS. Comparative studies on U–Pb age of the detrital zircons from northern and southern river sands in the STS belt provide constraints on the tectonic evolution of the STS belt and its surrounding blocks. Abundant 500–460 Ma detrital zircons in northern river sands probably reflect a bidirectional subduction of the Palaeozoic Central Tianshan Ocean under the Yili Block and the Central Tianshan Block. The 460–390 Ma zircon population in both northern and southern river sands likely implies a bidirectional subduction of the South Tianshan Ocean. A lack of the 380–320 Ma zircon grains in the southern river sands may indicates the northward subduction of the South Tianshan Ocean. A final collision between the Tarim Craton and the south‐western Central Asian Orogenic Belt possibly took place in the Late Carboniferous; the 310–260 Ma zircon population in both northern and southern river sands suggests syn‐ and post‐collisional magmatism. Based on the Hf isotopic signatures in the detrital zircon and magmatic zircons, we propose new constraints on the Palaeozoic crustal evolution of the STS. The continent formation in the STS belt was characterised by reworking of the ancient crust in a compressional environment during the Ordovician (ca. 460–440 Ma). Abundant significant juvenile materials progressively added to the crust through time in an extensional tectonic regime since Late Ordovician to Devonian (ca. 440–390 Ma). The crustal formation is mainly dominated by reworking of the Precambrian basement rocks with limited contribution of juvenile components input into magma formation during Late Carboniferous to Early Permian (ca. 310–260 Ma). [ABSTRACT FROM AUTHOR]

The central Inner Mongolia, located at the intersection of the northern margin of the North China Craton (NCC) and the Central Asian Orogenic Belt, is crucial for deciphering the Late Palaeozoic tectonic evolution associated with the subduction and closure of the Palaeo‐Asian Ocean (PAO). Our study focused on petrology, detrital zircon LA–ICP–MS U–Pb geochronology and whole‐rock geochemistry for the Late Carboniferous to Permian sandstones within the Shuanmazhuang, Dahongshan, Naobaogou, and Laowopu formations in Siziwang Banner, central Inner Mongolia. This comprehensive analysis shed light on the dynamic interplay between the NCC and the South Mongolia Block. Detrital zircon U–Pb ages in investigated samples mainly cluster between 250 and 2650 Ma, with significant peaks at 2.4–2.5 Ga, 1.8–2.0 Ga, 400–430 Ma, and 250–320 Ma, respectively. The geochemistry data are characterized by SiO2 contents (56.29–77.95 wt. %), Na2O / K2O ratios (0.45–1.58) and SiO2/Al2O3 ratios between 4.33 and 7.44. Moreover, they exhibit the slight enrichment in large ion lithophile elements (Rb and Ba) and the depletion in high field strength elements (Nb, Ta, Th, and U). These facts indicate that the sedimentary detritus predominantly originates from felsic sources, probably deriving from the Late Carboniferous–Permian continental island arc‐related intermediate‐acid igneous rocks, the Late Ordovician‐Silurian magmatic rocks in the Bainaimiao arc and the basements of the NCC. Furthermore, our present results also suggest that during the Early–Middle Permian, accelerating oceanic crust subduction triggered significant magmatic events in Siziwang Banner, leading to rapid uplift and the erosion of arc magmatic rocks, as well as the abundant corresponding sediments. Subsequently, the gradual convergence and eventual collision between the NCC and the Southern Mongolian Block took place at the end of the Permian, representing final closure of the PAO. [ABSTRACT FROM AUTHOR]

The basement complex of the Sierra Madre region in north‐eastern Mexico is classified into four domains: (a) granulite facies rocks of Grenville age (ca. 1 Ga) known as the Novillo Gneiss, (b) the Palaeozoic Granjeno Schist, (c) an unmetamorphosed succession of Palaeozoic marine siliciclastic and volcanic rocks, and (d) an Ordovician plagiogranite body. We present a geochemical and provenance study of the metasedimentary rocks of the Granjeno Schist, which are associated with metavolcanic and meta‐ultramafic rocks. In the Granjeno Schist, trace element ratios (Th/Sc, La/Sch, La/Sc, and Zr/Sc) and REE compositions of the metasedimentary rocks are similar to values for the mean continental crust values and are consistent with derivation of detritus from felsic rocks. Chemical index of alteration values of 30–80 indicates low to moderate weathering of the source. The clastic metasedimentary rocks have moderately radiogenic Nd‐isotopic compositions with initial εNd(t) values of −9 to −6, and model ages between 1.5 and 1.7 Ga. Ages of detrital zircon grains from the metasedimentary rocks are mostly 1.6–1.1 Ga, but some ages are 530–410 Ma. Such a Novillo Gneiss‐like age spectrum argues for short transport for the majority of zircon grains, with potential additional transport from the Maya Block. Na‐amphibole and mica geobarometer results of up to 6 kbar indicate high‐pressure subduction‐related metamorphism of the Granjeno Schist that was followed by a Pennsylvanian–Permian sub‐greenschist to greenschist metamorphic overprint in an accretionary prism. Thus, the Granjeno Schist is a representative of ocean‐plate stratigraphy that originated proximally close to a continent. [ABSTRACT FROM AUTHOR]

We report new detrital zircon U–Pb ages and Hf isotopic signatures of detrital zircons in Cambrian sedimentary rocks from the Ougarta Mountains of Algeria in the West African Craton (WAC) in order to provide constraints on the palaeo‐catchments of the Early Palaeozoic river systems draining Gondwana. The Cambrian sedimentary samples from the Ougarta Mountains have near‐identical age spectra with a dominant age peak at 618 Ma and an additional age peak at 2,035 Ma. The oldest detrital zircon grain is 3,407 Ma. The εHf(t) values of the 618 Ma age peak spans from εHf(t) +12 to −25 with a dominant mode at −1; the εHf(t) of the Palaeoproterozoic zircon ranges from 6 to −27 with an average of −10; the pre‐2,300 Ma zircon Hf lie along a crustal evolution trajectory (176Lu/177Hf = 0.01) back to the depleted mantle at ~3,100 Ma. The maximum depositional age of the sandstones in the Sebkhet el Melah Formation is constrained by the youngest detrital zircon age of 559 ± 13 Ma and by the underlying volcaniclastic rocks dated at 555 ± 7 Ma (Late Ediacaran to the Early Cambrian). The 618 and 2,035 Ma age peaks are consistent with a proximal provenance from the WAC, and it is possible that recycling of eroded material from the Cadomian arc and Pan‐African rocks may have been a potential source of the Ediacaran detrital zircons analysed herein. There were four (0.9%) Stenian detrital zircons identified in this study, and our results are consistent with the lack of WAC Stenian detrital zircon noted in previous studies, except those reported from a single Middle Cambrian sample in Morocco. Correlative sedimentary successions further to the east contain ubiquitous ca. 1.0 Ga detrital zircon that was likely supplied from the Trans‐Gondwana Mountain chain. It is noteworthy that the WAC and Sahara Metacraton are surrounded on three sides by Neoproterozoic orogenic systems, with the Rokelide, Dahomeyide, Pharuside, Anti‐Atlas, and Brasiliano orogens (reconstructed position from Gondwana palaeogeography) around the WAC and the Dahomeyide, Pharuside, East African orogen, and Oubangides orogens around the Sahara Metacraton. We posit these orogenic belts acted as drainage divides that controlled sediment routing pathways. Additionally, the occurrence of Stenian detrital zircon in Morocco could be explained by longshore drift coming from the east (present‐day coordinates). [ABSTRACT FROM AUTHOR]

The palaeogeographic reconstruction of the microcontinents on the northern margin of Gondwanaland and the tectonic evolution model of the Proto‐Tethys in the Early Palaeozoic remain controversial. The Baoshan and Lancang Blocks in SW Yunnan, China, were located on the northern margin of the Gondwana continent during the Early Palaeozoic. In this study, we present new zircon U–Pb ages and whole‐rock geochemistry data for the sedimentary rocks of the Lancang Group in the Lancang Block and the Mengtong Group in the Baoshan Block to reveal the nature of sedimentary provenance with a further tectonic evolution model of the Proto‐Tethys. Our new detrital zircon U–Pb results, in conjunction with the published age of the metamorphic volcanic rock interlayers, suggest that the Mengtong and Lancang groups were probably deposited during the Early Palaeozoic. The Mengtong and Lancang groups have similar detrital zircon age spectra and display three distinctive age peaks at 1.2–1.1 Ga, ~0.95 Ga, and 0.6–0.5 Ga. This implies that the Baoshan‐Lancang Block was situated in the transitional zone between India and Australia on the Gondwana margin and received detritus from both cratons. Combined with abundant volcanic rocks in the Lancang Group and SSZ‐type ophiolites in the Changning‐Menglian belt, the Lancang Block should be reconstructed as a continental island arc of the Baoshan Block in the Early Palaeozoic. The geochemical analysis results show that the sediments of the two strata were primarily sourced from felsic rocks in the upper crust, and they were deposited in the active continental margin. Combined with previous research, we propose a new tectonic evolution model for the Proto‐Tethys Ocean in the Early Palaeozoic, from bisubduction to collisional orogeny. [ABSTRACT FROM AUTHOR]

Detrital zircon U–Pb dating, Hf isotopic data, and Nd isotopic compositions of river sediments are used to constrain crustal evolution processes of their provenance in the South Qilian orogenic belt. The detrital zircons from the Yuka, Tataleng, and Bayinguole rivers range in age from Neoarchean (2,772 Ma) to Permian (261 Ma), with age peaks at ca. 2.4 Ga, ca. 1.95 Ga, and ca. 0.45 Ga. Hf isotopic compositions of Paleoproterozoic, Pan‐African, and Caledonian zircon age groups display a wide range of εHf(t) values, suggesting diverse sources of host magma of the zircon grains. The basement formation of the South Qilian orogenic belt from depleted mantle occurred at two stages; ca. 3.1–2.5 Ga and ca. 2.0–1.6 Ga. Meanwhile, the Nd model ages of silt‐mud from the region are between 1.98 Ga and 2.27 Ga with an average value of 2.12 Ga. Our study indicates that the Qilian oceanic plate formed between the Qaidam and Alxa blocks from late Neoproterozoic to Silurian. The South Qilian orogenic belt is a product of the Qilian Ocean closure and subsequent collision between the Qaidam Block and central Qilian belt during Ordovician–Silurian times. Combining regional tectonothermal events with new results of river sediments suggests that rifting from a continent and opening of the Qilian Ocean occurred at ca. 780–520 Ma, subduction of the oceanic crust at ca. 520–440 Ma, ocean closure and continental subduction at ca. 440–420 Ma, exhumation of subducted crust at ca. 420–400 Ma, and orogenic collapse and extension at ca. 400–360 Ma. [ABSTRACT FROM AUTHOR]

The geochemistry and detrital zircon geochronology of the Quemoco sandstones from the Woruo Mountain area, North Qiangtang Basin, are analysed to discriminate their provenance and tectonic setting. The sandstones were classified as litharenite according to their geochemical data. The index of chemical variability and SiO2/Al2O3 ratio values suggest that the compositional maturity and recycling are weak to moderate. The weathering indices, such as chemical index of alteration, plagioclase index of alteration, and chemical index of weathering, and A–CN–K (Al2O3–(CaO* + Na2O)–K2O) ternary plot reflect that the source areas have undergone a weak degree of weathering. The TiO2 versus Zr, La/Th versus Hf, and Co/Th versus La/Sc bivariate diagrams and multimajor elements discrimination diagram of Quemoco sandstones indicate that the provenances were primarily derived from felsic igneous rocks and may also have less intermediate igneous source rocks. The paleocurrent data and low composition and textural maturity of the Quemoco sandstones suggested that the provenances are mainly from the southwest of the study area and with proximal source features. The U–Pb ages studied here could be divided into 8 groups: 206–219 Ma, 268–283 Ma, 446–630 Ma, 700–970 Ma, 1006–1346 Ma, 1457–1843 Ma, 2087–2214 Ma, and 2331–2587 Ma. The provenances are mainly from the Central Uplift Belt and surrounding of the study area according to the detrital zircon ages and rare earth element parameters, which are composed of Late Triassic tuff, Permian basalt, Early Ordovician granite, Cambrian granite gneiss, and Precambrian crystalline basement. Two multidimensional tectonic discrimination diagrams based on major elements show a complicated tectonic setting composed of a collision, rift, and minor arc setting for the Quemoco sandstones, which is consistent with the nature of a rifted margin during the late Late Triassic. [ABSTRACT FROM AUTHOR]

To constrain the relationship between the plate boundary dynamics and the basin sedimentation in the southwestern South China Block (SCB), we undertook detrital zircon U–Pb–Hf isotope compositions of the Lower‐Middle Triassic turbidite system in the Youjiang Basin and biotite 40Ar/39Ar thermochronology of the adjacent Lingshan granite. The detrital zircons from Lower Triassic clastic rocks are dominated by age peaks at ~450 Ma and ~1,000 Ma and minor peaks at ~250–260 Ma with negative εHf(t) values (−6.4 to −10.1). In contrast, the Middle Triassic group contains more volcanic fragments and displays a different age peak at ~240–287 Ma with εHf(t) between −11.9 and 13.2 in addition to the former two peaks. These results suggest a potential provenance associated with juvenile and volcanic components in the adjacent region during the Middle Triassic. A summary of the Triassic tectonothermal history suggests that the eastern Youjiang Basin and Yunkai Terrane were uplifted throughout the Triassic, while the northeastern Indochina Block on the west of the SCB was uplifted mainly during the Middle Triassic. Combined with the palaeocurrent reconstruction, we infer that the turbidite system was filled primarily from east to west during the Early Triassic, mainly controlled by the Palaeo‐Pacific plate subduction. Subsequently, the Middle Triassic turbidite system involved juvenile and volcanic components from the eastern SCB and northeastern Indochina Block in addition to the Early Triassic provenance, as a result of dual impact from the Palaeo‐Pacific plate subduction and Indochina Block collision. [ABSTRACT FROM AUTHOR]

Reconstructing provenance in sandstones can be challenging, especially when the hinterland palaeogeology is unknown due to burial, diagenesis or weathering of the original outcrops. As sedimentary processes alter the distribution of minerals in the depositional environment, the use of multiple provenance methods reduces uncertainties, because, together, they can account for depositionally‐controlled textural and mineralogical re‐distribution in a basin. Here, we have applied petrography, X‐ray fluorescence geochemistry and sedimentology to understand the provenance of shallow marine Corallian sandstones with the aim of deducing the palaeogeology, palaeoenvironment and sediment distribution within the northern parts of the Upper Jurassic Weald Basin, onshore UK. The Corallian sandstones had a mixed mafic‐felsic (intermediate), metasedimentary recycled orogen source. The hinterland experienced significant physical and chemical weathering under humid conditions. Corallian sandstones were relatively more chemically mature up‐dip and more texturally mature down‐dip. Chemically unstable grains and heavy minerals were relatively concentrated down‐dip. Heterogeneous, sedimentologically‐controlled mineral distribution patterns highlight potential errors which may be made in deriving source‐area maturity. This study is significant as it illustrates the combined roles of provenance and deposition in controlling primary mineral distribution that then influenced the style of burial diagenesis. The work presented here emphasizes the importance of a multi‐proxy approach to improve provenance analysis. [ABSTRACT FROM AUTHOR]

Jurassic terrestrial sediments of the Jianggalesayi–Washixia Basin in the northwestern Altyn Tagh Orogen record abundant information regarding the evolution and uplift of the orogen. Investigation of this orogen is critical to establishing whether the Tarim and Qaidam basins were connected during the Jurassic. In this study, we present 474 single‐grain laser‐ablation–inductively coupled plasma–mass spectrometry detrital zircon U–Pb ages obtained from five Jurassic sandstone samples collected from four sections in the basin. Detrital zircons from the Lower Jurassic strata yield age populations of 997–726 and 551–509 Ma, indicating that the zircons were derived mainly from the southern–central Central Altyn Tagh Massif. Zircon age populations from the lower Middle Jurassic strata are 1024–838, 778–643, and 543–357 Ma, which suggest that the sediments were derived predominantly from the northern Central Altyn Tagh Massif and the southern South Altyn Tagh subduction–collision complex belt (SATSB). Zircon age populations from the upper Middle Jurassic strata are 980–830, 556–424, and 277–245, suggesting that these sediments were derived from the central SATSB. Detrital zircons from the Upper Jurassic strata display age groups of 515–387 and 325–226 Ma, indicating that these sediments originated from the northern SATSB. Uplift of the Altyn Tagh Orogen was initiated during the Middle to Late Triassic as a synchronous far‐field response to the collision of the Qiangtang Block with the Eurasian Plate. By the Early Jurassic, the Qaidam Basin was no longer connected with the Tarim Basin. During the Late Jurassic to Early Cretaceous, the collision of the Lhasa Block with the southern margin of the Eurasia Plate led to further uplift of the Altyn Tagh Orogen. [ABSTRACT FROM AUTHOR]

Source‐to‐sink system studies in oil fields are especially important for optimizing the favourable oil‐gas areas; however, this basin‐mountain interaction process is particularly complicated in intermontane basins. In this study, detrital zircon U–Pb dating of 8 new and 3 published samples from throughout the Jurassic in the central Turpan Basin (TB) are combined with collected heavy mineral data to investigate the evolution of the source‐to‐sink system and reconstruct the filling process of this intermontane basin from the Lower to Upper Jurassic. Based on the detrital zircon ages and heavy mineral assemblage, the filling rocks mainly weathered from Mesozoic, Palaeozoic and Precambrian volcanic and metamorphic rocks in the Tian Shan (TS) area, and the source‐to‐sink systems in the basin show a clear alteration corresponding to the uplift of the surrounding mountains during the Jurassic. In the Lower Jurassic, the uplifted central and northern TS was the main provenance and shed the most source rocks northward, and the gentle positive relief of the Bogda Mountains (BM), the northern boundary of the TB, was a secondary provenance and provided limited material to the northern area. In the early Middle Jurassic, these provenances did not alter much, but in the later Middle Jurassic, uplift of the western BM began and provided some extreme new source rocks with detrital zircon ages of approximately 159–172 Ma. In the Upper Jurassic, the considerably uplifted BM became the main provenance, while the still gently uplifted central and northern TS became the secondary provenance. [ABSTRACT FROM AUTHOR]

Geochronological dating of detrital minerals from sedimentary rocks can provide invaluable records of the erosional and unroofing history of orogenic systems and link specific sources with their sinks in sedimentary basins. Aiming to establish a better understanding of the thermal and erosional evolution of the East Kunlun Orogenic Belt (E‐KOB), northern Tibet Plateau during the Mesozoic, integrated detrital U–Pb zircon, and 40Ar/39Ar muscovite dating was applied to Triassic and Jurassic strata in the southern E‐KOB in this study. Detrital U–Pb zircon ages of clastic rocks from Triassic and Jurassic formations show major age populations at 2,600–2,200 Ma, 2,000–1,700 Ma, 1,000–600 Ma, 530–340 Ma, and 320–220 Ma, while the 40Ar/39Ar dating of detrital muscovite yield dominantly Devonian ages with uniform early‐middle Devonian peak ages (380–405 Ma). Our new detrital U–Pb zircon and 40Ar/39Ar muscovite ages, combined with the previous palaeocurrent data and comparison with published U–Pb zircon, and 40Ar/39Ar muscovite ages of potential source areas, suggest that the E‐KOB was the major source for Triassic and Jurassic strata in the southern East Kunlun. Devonian detrital muscovite 40Ar/39Ar ages of the Triassic and Lower Jurassic strata are consistent with the age of syn‐ and post‐collisional magmatic activity in E‐KOB related with the post‐collisional thermal relaxation after closure of the Qimantagh back‐arc basin. The Lower Triassic sedimentary deposits were associated with the subduction of the Kunlun Ocean, which is part of the Palaeo‐Tethys Ocean. The E‐KOB‐derived material in Upper Triassic and Lower Jurassic formations implies that significant surface uplift, unroofing and erosion occurred during the Late Triassic and continued into the Early Jurassic in the East Kunlun region. [ABSTRACT FROM AUTHOR]

This study provides an insight to the provenance of the Late Cretaceous Pab Formation exposed in the Sulaiman fold‐thrust belt, Pakistan. The methodology adopted consisted of sandstone petrography and U–Pb detrital zircon geochronology. The sandstone petrography indicates craton interior and recycled orogenic provenances that points to an Indian provenance. The observed basaltic lithics were possibly derived from Rajmahal traps instead of Deccan traps, supported by younger detrital age. The detrital zircon ages exhibit a resemblance to the central and southern Indian provenances, while some detritus also matches the age spectrum of Tethyan Himalayas (~400–800 Ma). Combining sandstone petrography and U–Pb geochronology results, it is suggested that in the Late Cretaceous time, the sediments were mainly fed by the southern and central sources of the Indian Craton. This provenace is possible, as during the Cretaceous time, thermal doming of Indian Plate in the southern part occurred when it was passing over a mantle hotspot. This movement over the hotspot uplifted the southeastern region and increased sediment supply from southern and central Indian provenances and deposited along the western margin as the Pab Formation. [ABSTRACT FROM AUTHOR]

Junggar Basin is an important exploration zone for sandstone‐hosted uranium deposits in north‐west China. However, neither the provenance of the host sandstone nor the uranium supply capacity of the potential source rocks have been well evaluated. To determine the provenances of the Mesozoic to Cenozoic sandstone grains and to evaluate relationships between the uranium source and the detritus provenances, a field investigation was performed at the Honggou section in the southern Junggar Basin. U–Pb geochronology and Hf isotopes were obtained from populations of detrital zircons from Jurassic through Palaeogene sandstones. The detrital zircon U–Pb ages display three main groups: 145–190 Ma, 250–360 Ma, and 360–460 Ma. The detrital zircon age distributions and the Hf isotopic characteristics of the sandstones correspond to different igneous rock units within the North and Central Tianshan Mountains. Therefore, the changes in the relative proportions of the zircon age populations indicate that there were major shifts of the provenance areas for the sandstones throughout the Early Jurassic to Palaeogene interval. The majority (92%) of Hf isotope εHf(t) values are positive and in the range of +0.7 to +15.5, which indicates that the majority of the zircons had crystallized in igneous rocks that were mainly derived from juvenile crust or depleted mantle. The majority (93%) of the two‐stage model ages (TDM2) are less than 1.8 Ga, thereby indicating the source of the majority of the igneous rocks was from the melting of ancient Meso‐Proterozoic juvenile crust. Carboniferous–Permian intermediate‐felsic igneous rocks in the Tianshan Mountains may be the primary source of released mobilized uranium and uranium‐enriched siliciclastics into the southern Junggar Basin. This study will assist in future uranium prospecting in this region. [ABSTRACT FROM AUTHOR]

A well‐developed 86 m‐thick Cenozoic sedimentary succession in the Matanomadh area, western Kachchh, was studied to assess the stratigraphic positions of different units, ascertain depositional environments, and the degree of climatic controls over time depositional processes. Age‐diagnostic nannoplankton species Cyclicargolithus floridanus (46.29–12.1 Ma), Reticulofenestra dictyoda (53–30.8 Ma), Reticulofenestra minuta (50.5–2.59 Ma) and foraminiferal species, for example, Orbulinoides beckmanni (41–39.5 Ma) found across studied units envisage the stratigraphic age and palaeoenvironment. CaO with strong negative elemental correlation, binary/ternary discriminant tectonic and depositional regimes cross‐plot from units indicate the biogenic origin of limestones and shales were formed in typical passive, marginal, shallow littoral settings with plausible detritus influx from Deccan basaltic provenance. Total organic carbon with TE‐REE respectively connotes a sedimentation process in a nearly consistent open shallow marine, locally transient semi‐restricted marginal basin in a tropical‐equatorial region. Furthermore, principal component analysis (PCA) of weathering indices based on elemental abundance and X‐ray diffraction data of clays deterministically suggest with empirical relation between humid tropical climate‐induced weathering and fluctuant terrestrial influx. Palaeoredox indices with biological data demonstrate localized redox‐stratified conditions. However, coherent signatures of the global events such as Eocene Thermal Maximum‐2, Middle Eocene Climatic Optimum, and Mid Miocene Climatic Optimum can be traced and validated by synthesizing geochemical data for direct/indirect estimation of sediment routing, rainfall (αAlMg and αAlCa) and climate proxies (PCA), productivity indices (Babio, Cubio and Nibio), and localized periodic oxic‐dysoxic environment (V/Cr, U/Th, Ni/Co) from core samples. [ABSTRACT FROM AUTHOR]

The north‐eastward extrusion of the Tibetan Plateau has always been under debate. The arcuate tectonic belt is located at the north‐east margin of the Tibetan Plateau and bears crucial information about the tectonic and geomorphic evolution of north‐east Tibetan Plateau. Combined with sedimentary sequence, detrital zircon U–Pb geochronology, and heavy mineral combinations, significant provenance transformation can be determined both in the south‐west and north‐east of the arcuate tectonic belt during the Eocene to Miocene. The far‐field effect of north‐eastward extrusion of the Tibetan Plateau first arrived at the south‐west of the arcuate tectonic belt during the Miocene and resulted in the angular unconformity between the Eocene Qingshuiying period and Miocene Zhangenbao Formation. Then the regional exhumation spread from south‐west to north‐east across the arcuate tectonic belt, and sedimentary hiatus developed between the Miocene Zhangenbao period and Pliocene Ganhegou period. Therefore, tectonic uplift and mountain building of the arcuate tectonic belt expanded north‐eastward during the Eogene to Neogene. This research shed new insights on the north‐eastward extrusion of the Tibetan Plateau from the coupling relationship between basin and range. [ABSTRACT FROM AUTHOR]

The mineralization in this area is more closely related to the shoshonitic Niuxinshan meddling complex (NIC), which helps to depict concurrent edge magmatism metallogeny. In the present investigation, new geochronological and geochemical data are combined with previously disseminated isotopic data from granitic rocks in the NIC to establish the situation of the region's structural setting change and determine its bearing on territorial metallogeny. The new geochronological data suggest that structural change could have occurred between 155 and 185 Ma. The granitic rocks of the NIC can be geochemically divided into two groups. The geochemical signature of one group displays high rare earth element (REE) designs with irrelevant Eu anomalies, lower Yb, higher Sr, and negative Nb–Ta–Ti (NTT) abnormalities, demonstrating a volcanic‐curve climate with a thickened outside layer in a focalized setting. The other group has level REE designs with obvious regrettable Eu anomalies, higher Yb, lower Sr, and moderate NTT anomalies, indicating an intra‐plate extensional climate with a decreasing outside. According to geochronologic and isotopic data, the mineralization is Late Jurassic (155 Ma). This has been deciphered to be hereditarily associated with the crystallization of the complex's shallow crustal‐sourced bits. In addition, a structural model is presented that provides a possible explanation for the abundant polymetallic mineralization that occurs in the northern margin of the NCC after 155 Ma. [ABSTRACT FROM AUTHOR]

The Geo‐chronology of the Mesozoic sequences from the northern Ordos Basin provides an excellent window for understanding the source‐to‐sink analysis and tectonic settings. In this study, nine groups of detrital zircon U–Pb ages from the Middle Triassic to Lower Cretaceous strata of the northern Ordos Basin are presented. Three dominant age groups are revealed through the kernal density estimation: ca. 2,300 ~ 2,500 Ma (Siderian), ca. 2,050 ~ 1,800 Ma (Orosirian), and ca. 358.9 ~ 298.9 Ma (Carboniferous). Significant differences are distinguished according to multidimensional scaling analysis and cumulative distribution function. The Middle Triassic sample is the closest to the Yin Mts and the upper Triassic and lower Jurassic samples have significant similarities with the Jining area. The samples YA‐1 and ZL‐1 from the Middle Jurassic sequences are the closest to the Daqing Mts (DQS) and Wula Mts (WLS), respectively. The sample ZL‐1 is the second closest to the DQS. The sample YJ‐1 from the Lower Cretaceous sequences has apparent affinities with multiple resources, including the DQS, WLS and samples EM‐1 and AD‐1, while the sample LH‐1 only resembles the sample YA‐1. Overall, the northern Ordos Basin experienced three stages of transformations in the source areas: (a) Southward migration during the Middle Triassic and the Early Jurassic; (b) Westward migration during the Early Jurassic and latest Middle Jurassic; (c) Southward migration during the latest Middle Jurassic, and multiple resources and recycled sediments for the Cretaceous sequences. The transition to the North China Craton's (NCC) extensional tectonic setting was closely related to the transformation from the Palaeo‐Asian Ocean's closure to the Palaeo‐Pacific Plate's subduction during the Early Jurassic. The multiple resources and recycled resources for the Lower Cretaceous sequences were related to the destruction of the NCC. [ABSTRACT FROM AUTHOR]

The bauxite and clay deposits of Western Henan, located in the southern part of the North China Craton (NCC), are rich reserves of bauxite ore, and the provenance of this bauxite has received much attention. In this study, X‐ray diffraction and detrital zircon U–Pb dating (using laser ablation–inductively coupled plasma–mass spectrometry) were applied to determine the source(s) of the bauxite in the Carboniferous Benxi Formation. Our data, combined with regional geological and geochemical observations, suggest that detrital zircons from the deposits with ages of ca. 457 Ma were derived mainly from Caledonian intermediate–acidic granitic rocks of the North Qinling Orogenic Belt (NQOB). Zircon grains with Precambrian ages of 2,713 to 549 Ma may have been derived from metamorphic rocks within the NQOB. The Benxi Formation bauxite in this area lacks late Palaeozoic zircons, which may be related to its location, as it is proximal to the NQOB but far from sources of late Palaeozoic zircons in the Inner Mongolia Uplift. [ABSTRACT FROM AUTHOR]

Detrital mineralogy, major oxides, trace, and rare earth elements (REE) were examined in the Middle Jurassic Fort Member Sandstone (FMS) of the Jaisalmer Formation in Western India to understand palaeoweathering, provenance of sediments, and to decipher the tectonic setting. The sandstones are classified as arkose to sub‐litharenite types according to their relative percentages of quartz, feldspar, and lithic fragments, and major elemental ratios. The values of Chemical Index of Alteration (67–85), Plagioclase Index of Alteration (78–97) and Chemical Index of Weathering (83–97) along with A‐CN‐K diagram suggest moderate to intense chemical weathering in the source region. Presence of fresh feldspars and dominance of monocrystalline quartz, showing both parallel and undulose extinction, indicate plutonic and volcanic felsic igneous provenance. Contribution from metamorphic orogen sources is indicated by the lithic fragment population. Various geochemical parameters such as Th/Sc, Cr/Th, Ti/Zr, and Eu/Eu* support a dominant felsic provenance. Higher Zr/Sc ratios relative to the magmatic Zr/Sc‐Th/Sc trend, higher Zr and Hf concentrations in the FMS indicate some extent of sedimentary recycling and zircon sorting. LREE enrichment, flat HREE pattern, negative Eu anomaly and trace element ratios, in conjunction with palaeocurrent data, indicate a likely sediment contribution from basement source terrains including Erinpura‐Mount Abu‐Sirohi granites, Malani Igneous Suite, and Aravalli‐Delhi orogens. The major and trace element tectonic setting discrimination diagrams for the FMS indicate a passive margin setting. [ABSTRACT FROM AUTHOR]

The geochronology of tuffaceous sandstone and elemental geochemistry of mudstones in the Lower Permian Zhanjin Formation (well QZ‐5) in the Central Qiangtang Basin were studied to determine their depositional age, provenance, tectonic setting, and depositional conditions. Twenty‐six synchronous igneous zircons from tuffaceous sandstone at 596.5 m have a weighted average U–Pb age of 292.5 ± 2.5 Ma, tentatively constraining the sedimentary age of the Zhanjin Formation to the Early Permian. Low SiO2/Al2O3 and Th/Sc ratios indicate a low sedimentary recycling and compositional maturity for the source area of the Zhanjin Formation mudstones. The low Al2O3/TiO2, moderate‐high Fe2O3/Al2O3, high TiO2/Fe2O3, low‐moderate TiO2/Zr, and moderate Co/Th ratios combined with post‐Archean Australian shale‐normalized rare earth element distributions imply that the provenance of the Zhanjin Formation mudstones was mainly from the mixed mafic and felsic sources that is composed of basalt and rhyolite exposed in the Central Qiangtang Basin. The tectonic discrimination plots, low Fe2O3/TiO2, (La/Ce)N, and high Al2O3/(Al2O3 + Fe2O3) ratios reveal that the studied mudstones mostly formed in rift settings, consistent with the geologic evolutionary history of the Early Permian Qiangtang Basin. Trace element ratios (V/Cr and Cu/Zn), enrichment factors (MoEF), and δCe values combined with sedimentary features indicate that almost all the studied mudstones were deposited in an open marine environment along the continental margin, and were associated with oxic and dysoxic water columns. [ABSTRACT FROM AUTHOR]

In the Late Mesozoic, the Eastern North China Craton changed from being controlled by the Palaeo‐Asian tectonic domain to the marginal Pacific tectonic domain. The Eastern North China Craton transformed the E–W compression to NNE–SSW extensional tectonics under the influence of two tectonic domain transformations. However, the timing of the transformation of the tectonic domains remains controversial. The North Yellow Sea Basin is located in an important position in the Eastern North China Craton at the junction of the Pacific and Eurasian plates and is controlled by two tectonic domains. Therefore, the sediments in the basin are faithful records of the transformation of the two tectonic domains. Based on the latest and high‐precision detrital zircon U–Pb dating data, sandstone modal analysis, and elemental geochemical analysis in the North Yellow Sea Basin combined with regional tectonic, palaeontological, and palaeoclimatic evidence, this paper discusses the provenance from the Middle Jurassic to Early Cretaceous, which responds to the Late Mesozoic tectonic domain transformation in the Eastern North China Craton, and provides important evidence of provenance in the North Yellow Sea Basin to determine the time of tectonic domain transformation. These results suggest that the source rocks of sediments in the North Yellow Sea Basin have changed from ancient sediments (ancient craton/recycle orogenic belt) in the Middle Jurassic to Late Jurassic, to felsic igneous rocks in the Early Cretaceous. The peak of zircon U–Pb ages changed from 234, 1,842, and 2,429 Ma in the Late Jurassic to 217 and 1,871 Ma in the Early Cretaceous. The provenance changed from the Sulu Orogenic Belt and Precambrian basement of the Jiaodong Peninsula in the Late Jurassic, to the igneous rocks and Precambrian basement of the Liaodong Peninsula and Korean Peninsula in the Early Cretaceous. The provenance direction of the sediments changed from south‐west in the Late Jurassic to the north and south‐east in the Early Cretaceous. The tectonic setting of the basin changed from compression to extension. The changes in the peaks of zircon U–Pb age, characteristics of the source rocks, provenance direction, and basin tectonic setting in the Middle Jurassic to Early Cretaceous in the North Yellow Sea Basin are a response to the change from E–W compression to NNE–SSW extensional tectonics caused by the transformation of two tectonic domains. In the Early Cretaceous, the Eastern North China Craton completed the transformation of two tectonic domains that were influenced and controlled by the marginal Pacific tectonic domain. [ABSTRACT FROM AUTHOR]

U–Pb dating and Hf isotopes of detrital zircons from the Nanhua System in Longsheng, northern Guangxi, were investigated to determine the depositional age and provenance of the Nanhua System and the early crustal evolution stages of the South China. U–Pb ages of detrital zircons from the Chang'an Formation of the Nanhua System in Longsheng, northern Guangxi, are mainly 0.66 ~ 0.72 Ga and 0.72 ~ 0.90 Ga, with εHf(t) ranging from −17.05 to 12.79. The dominant provenance is composed of Neoproterozoic magmatic rock from the southeastern margin of the Yangtze Block and the Nanhua period detrital material from Cathaysia Block. U–Pb ages of detrital zircons from the Fulu Formation can be divided into four major groups, that is, 0.64 ~ 0.72 Ga, 0.72 ~ 0.90 Ga, 1.80 ~ 2.20 Ga, and 2.30 ~ 2.80 Ga, with εHf(t) ranging from −27.66 to 11.68. The main provenance is Neoproterozoic magmatic rock from the southeastern margin of Yangtze Block, followed by the Nanhua period detrital material from the Cathaysia Block and geological body equivalent to the assembly of the Columbia Supercontinent. U–Pb age of detrital zircons from Lijiapo Formation is concentrated in 0.72 ~ 0.90 Ga, with εHf(t) ranging from −16.02 to 11.87, and the main provenance comes from Neoproterozoic magmatic rock in the south‐east margin of Yangtze Block. The second‐stage Hf model age (TDM2) of the Nanhua System is 0.84 ~ 4.51 Ga, with two obvious peak intervals of 0.90 ~ 1.30 Ga and 1.40 ~ 2.10 Ga, and two secondary peak intervals of 2.40 ~ 3.00 Ga and 3.10 ~ 3.60 Ga, which can be interpreted that the research area has experienced four stages of crustal growth: 3.10 ~ 3.60 Ga, 2.40 ~ 3.00 Ga, 1.40 ~ 2.10 Ga, and 0.90 ~ 1.30 Ga. The detrital zircon age spectra indicate that the Chang'an Formation and Fulu Formation of the Nanhua System contain more detrital zircons which is contemporaneous with strata due to the Xuefeng orogeny, while the Lijiapo Formation contains a very small amount of detrital zircon which is contemporaneous with strata, suggesting that the tectonic setting has shifted to a passive continental margin or pull‐apart basin during the period of the Lijiapo Formation. [ABSTRACT FROM AUTHOR]

The depositional environment and sediment provenance of the third member of Palaeogene Shahejie Formation (Es3) in the Nanpu Sag of the Bohai Bay Basin, eastern China, are reconstructed by analysing trace element and rare earth element (REE), and the formation mechanism of organic‐matter‐rich shales of the same member is also evaluated. These results show that the terrigenous detrital supply in the Nanpu Sag was relatively sufficient during the Es3 interval, and the total REE contents range from 148.23 to 319.28 ppm, close to or higher than that of the upper crust. The Sr concentrations are 214.22–525.54 ppm and the Sr/Ba ratios are 0.31–0.74, which represent the coexistence of fresh, brackish, and saline waters during the Es3 interval. The V/(V + Ni) ratios of 0.71–0.82, Th/U ratios of 0.82–4.05, and positive δCe anomaly confirm that the water column was suboxic condition, with moderate stratification during the Es3 interval. Comparison of REE behaviours suggests that the Es3 sediments were primarily derived from Yanshanian granites at the Yanshanian fold belt at the active continental margin. The development of organic‐matter‐rich shales in the Es3 member in the Nanpu Sag was closely related to major palaeoenvironmental and palaeogeographical variations in that time, which can be summarized: (a) suitable palaeosalinity as well as sufficient nutrients in water column contributed to the boom of various planktonic algae, improving the production efficiency of aquatic organic matter; (b) suboxic water column slowed down the degradation of oxygen‐sensitive materials during the burial process, enhancing the preservation efficiency of aquatic organic matter. [ABSTRACT FROM AUTHOR]

The Late Precambrian Wufoshan Group from the southern North China Craton (NCC) is significant for its contribution to our understanding of the Precambrian evolution of the NCC, which consists of the Lower Ma'anshan, Upper Ma'anshan, Puyu, Luotuopan, and Hejiazhai formations. Detrital zircon U–Pb ages and Lu–Hf isotopes from the Puyu, Luotuopan, and Hejiazhai formations are used in this study to constrain the depositional age and provenance of the Wufoshan Group and crustal evolution of the NCC. The Puyu Formation is characterized by detrital zircon U–Pb age populations of ~2.13 Ga and ~2.50 Ga, similar to the Lower–Upper Ma'anshan formations from the literature. The Luotuopan Formation exhibits age populations of 1.85–2.18 Ga and 2.28–2.98 Ga, with mainly negative εHf(t) values and scattered positive εHf(t) values clustering at two groups of 2.48–2.52 Ga and 2.64–2.97 Ga. The Hejiazhai Formation displays age populations of 0.98–2.00 Ga and 2.51–2.79 Ga with mainly positive εHf(t) values, whose depositional age is constrained as Neoproterozoic era by the youngest graphical detrital zircon age of 976 ± 20 Ma. Provenance studies indicate that the Mesoproterozoic Lower–Upper Ma'anshan and Puyu formations were sourced from the middle Trans‐North China Orogen (TNCO), while the Neoproterozoic Luotuopan and Hejiazhai formations were derived from the southern TNCO and the North Qinling Terrane, respectively. The clastic rock series in the southern NCC is divided into Luotuopan type and Hejiazhai type by detrital zircon U–Pb age pattern and Hf isotopic characteristics, suggesting Late Mesoarchean to Early Palaeoproterozoic (2.47–2.97 Ga) crustal growth in the interior NCC, and Late Palaeoproterozoic to Early Neoproterozoic (0.98–2.08 Ga) crustal growth in the marginal NCC. The crustal evolution of the NCC can be classified into three stages, namely >3.0 Ga continental nuclei generation, the Meso‐Neoarchean massive growth, and the Palaeo‐Mesoproterozoic interior reworking and marginal growth. [ABSTRACT FROM AUTHOR]

The Great Unconformity between the Precambrian basement and the Phanerozoic successions marks a major gap in the stratigraphic records globally. However, previous studies on the time, magnitude, and the spatial distribution of this unconformity in the North China Craton (NCC) mainly focused on the south‐eastern margin and were seldom investigated in the central area. In this study, we report detrital zircon geochronological data of the Huoshan Formation, a siliciclastic stratigraphic unit between the Archean‐Palaeoproterozoic metamorphic basement and Cambrian successions in the central NCC. The youngest age peak of 685 Ma suggests that the Huoshan Formation was formed in the post‐Ediacaran rather than the counterpart of the lower Palaeo‐Mesoproterozoic Changcheng Group. The detrital zircons of the quartz sandstone from the Huoshan Formation show varied age populations of 2,700–2,600 Ma, 2,600–2,500 Ma, 2,200–2,000 Ma, 1,900–1,800 Ma, and 700–600 Ma, which correspond to typical tectono‐thermal events of the NCC. First, the widely developed Precambrian tectono‐thermal events in the NCC were archived in the detrital zircons in the Huoshan Formation, for instance, the crustal growth event at 2,600–2,500 Ma and the 1,850–1,800 Ma magmatic and metamorphic events. Second, the age peaks younger than 1,000 Ma are not distinct in the NCC and are possibly from other terranes. The Great Unconformity represented by the boundary between the Huoshan Formation and the underlying Archean‐Palaeoproterozoic basement suggested a high topography and long‐term denudation in the Lüliang area during the transition from the Proterozoic to the Phanerozoic. [ABSTRACT FROM AUTHOR]

The provenance of Devonian sandstones of the Padeha Formation (Fm.), Eastern Alborz in Iran, has been investigated by standard heavy‐mineral analysis and tourmaline and rutile geochemistry. Heavy‐mineral assemblage is dominated by the ultra‐stable tourmaline, zircon, and rutile, while unstable species are completely absent. The Padeha Fm. sandstones show a very high value of zircon‐tourmaline‐rutile index signalizing either strong weathering in source area(s) or their recycled origin in older Early Palaeozoic formations. Detrital tourmaline shows predominantly dravitic, lesser Mg‐foititic, and uvitic compositions and metasedimentary origin. Metapelitic source is also indicated by rutile geochemistry. Temperature estimates according to Zr‐in‐rutile thermometry show a wide range from 519 to 872°C and indicate the presence of low‐ to upper‐amphibolite and granulite facies metapelitic rocks. Based on chemical composition of detrital tourmaline and rutile, we inferred that the crystalline basement rocks of the Arabian–Nubian Shield were potential primary sources for the Padeha Fm. deposits. Shape of tourmaline and rutile as well as their microtexture surface features indicate long‐distance transport, storage, and recycled history. [ABSTRACT FROM AUTHOR]

The depositional history of the Himalayas has been overprinted by the tectonic activities during the Himalayan Orogeny. A detailed investigation of the sedimentary units can provide crucial information regarding their depositional history and provenance. This study aims at constraining the weathering history, tectonic setting, and provenance of meta‐sediments from the Shimla and Chail Groups of Outer Lesser Himalaya. With similar major element chemistry, these meta‐sediments comprise a low‐silica group (avg. SiO2/Al2O3 <3.29). Weathering intensity parameters chemical index of alteration (CIA), plagioclase index of alteration (PIA) and index of chemical variability (ICV) range from 62 to 78 (avg. = 69.41), 70 to 96 (avg. = 85.34), and 0.45 to 1.45 (avg. = 1.01), respectively indicating moderate to severe degrees of weathering. Transition element ratios [Cr/V (1.68–5.18), Ni/Co (1.47–30.99), and V/Ni (0.87–4.61)], and trace element bivariate plots suggest a recycled, felsic to intermediate provenance that has primarily been derived from Post‐Archean sources with minor inputs from Archean units. A passive margin depositional setting with arc‐derived sources is suggested for the Chail and Shimla meta‐sediments. Rare‐earth element patterns reveal similarities between the studied metasediments with TTG gneisses and sanukitoids from the Aravalli and Bundelkhand Cratons, as well as Chaur and Jutogh granitoids. Therefore, Neoproterozoic Himalayan granitoids and Archean Aravalli‐Bundelkhand granitoids (TTGs and high‐K granitoids) could be potential sources of these meta‐sediments, as also suggested by the detrital zircon age distribution from the Beas‐Satluj‐Pabbar valleys and Shimla Group. [ABSTRACT FROM AUTHOR]

The Kuhai–Saishitang area, which can be divided into the Tongyugou–Saishitang and southern Kuhai areas, is located in the northeastern Tibetan Plateau. Numerous Cu deposits have been discovered in the Tongyugou–Saishitang area, with the ore‐forming materials being derived from both sedimentary rocks and igneous intrusions. In contrast, no deposits have been found in the southern Kuhai area. The mineralization potential in the southern Kuhai area remains unclear. We collected a siltstone sample from the Tongyugou–Saishitang area and a sandstone sample from the southern Kuhai area for zircon LA–ICP–MS U–Pb dating, which yielded the youngest ages of 228 and 277 Ma, respectively. The samples exhibit similar age spectra, suggesting that these rocks have a common source. Detrital zircons from the samples can be divided into five groups on the basis of their U–Pb ages: Early Mesozoic–Late Palaeozoic (228–335 Ma), Early Palaeozoic (372–565 Ma), Neoproterozoic (645–995 Ma), Mesoproterozoic (1,154–1,693 Ma), and Paleoproterozoic–Neoarchaean (1,827–3,128 Ma). On the basis of a detailed comparison of the age spectra with those in the adjacent regions, we propose that the sedimentary rocks of the Kuhai–Saishitang area have an identical provenance that was derived mainly from the northern margin of the Qaidam Basin during the Middle–Late Triassic. The southern Kuhai area is also a potential target for further Cu exploration. [ABSTRACT FROM AUTHOR]

The Lower Jurassic clastic rocks in the Qiangtang Basin, northern Tibet, are generally regarded as the early sediments of the new Mesozoic Qiangtang Basin (Late Triassic to Early Cretaceous). However, little attention has been paid to the palaeoenvironment, provenance, and tectonic setting of this unit. The QZ‐16 well, located in the east of the northern Qiangtang Basin, firstly recovered the Lower Jurassic strata (Quemo Co Formation) in the Qiangtang Basin. In this paper, the whole‐rock major‐trace elemental characteristics of 34 mudstone samples and detrital zircon geochronology of one sandstone, collected from the Quemo Co Formation of the QZ‐16 well, are reported in order to infer the palaeoenvironment, provenance, and tectonic setting. Quemo Co mudstones are dominated by SiO2 and Al2O3, while Fe2O3, CaO, K2O, and MgO are the second most abundant oxides. They are generally characterized by high REE concentrations, enrichment in light rare earth elements (LREEs), marked negative Eu and Ce anomalies. The REE contents of the mudstones are mainly controlled by terrigenous detrital minerals input. The Lower Jurassic mudstones have relatively high chemical index of alteration (79.1–83.6) values, indicating moderate to high degree of chemical weathering conditions of the source area. Sr/Ba and Rb/K ratios reflect that the marine transgression impact was limited and the mudstones were generally deposited in a brackish water environment. Major, trace, and REE contents indicate that the mudstones were mainly derived from intermediate igneous rocks with subordinate felsic igneous rocks. Prominent age peaks at ca. 200 ~ 400 Ma, 700 ~ 970 Ma, 1,700 ~ 1,900 Ma, and 2,100 ~ 2,700 Ma of the detrital zircon grains suggest that the Lower Jurassic clastic rocks were derived from the Central Qiangtang and Songpan–Ganzi complex. Moreover, tectonic discrimination diagrams based on major and trace elements show that the source of the Lower Jurassic sediments were most likely derived from a collision tectonic setting. [ABSTRACT FROM AUTHOR]

The stratigraphic records of Palaeocene‐Eocene are studied with interest as they encompass significant high‐resolution information on the environmental and climatic signals. Here, we present whole‐rockgeochemistry, mineralogy, and petrography of the turbiditic sedimentary rocks of the Upper Kelalan Formation, NW Borneo, and constraints on palaeoweathering, tectonic setting, and provenance. These are fine‐medium‐grained, poor to moderately sorted, angular to sub‐rounded litharenites with lesser occurrences of arkose, wacke, and Fe‐sandstone. The dominant proportion of monocrystalline and polycrystalline quartz, followed by K‐feldspar and plagioclase and minor amounts of lithic fragments, zircon, etc., with nil‐appreciable quantities of clay occur in these rocks. Chemical weathering indices (CIA, CIW, and PIA) values and A‐CN‐K plot show that the source area has undergone a moderate to an intense degree of chemical weathering and also influenced by the recycling effect. The majority of the sediments are derived from the felsic source area (i.e., granites) with some minor input from the metasedimentary/metamorphic terrain. Based on the geochemical ratios and discriminant diagrams, it is determined that the Schwaner Mountains and its metamorphic group of rocks were the principal provenances with some input from West Borneo Group of rocks. Our data suggest the sediments were deposited initially in an active continental margin setting during the Palaeocene that may have shifted to a passive margin setting during the Eocene age. [ABSTRACT FROM AUTHOR]

Early Permian basins formed during a major phase of crustal extension are common throughout eastern Gondwana. One of these basins, the Sydney Basin, has not been subjected to geochemical studies aimed at determining the sedimentary provenance and the tectonic setting. This study provides new geochemical data of the Lower Permian siliciclastic successions in the southern edge of the Sydney Basin. Published petrographic analysis indicates a source area containing sedimentary, felsic volcanic, plutonic, and low‐grade metamorphic rocks. Major, trace and rare earth element data suggest that the clastic rocks are geochemically mature and originated from a continental source that has been subjected to moderate to strong weathering. Further, they indicate that most source rocks were of felsic composition and that only the oldest sediments possess a more mafic signature. The provenance data presented in this study, along with published palaeocurrent data, point to the Lachlan orogen being the main source of sediments for the basin. Multi‐dimensional discrimination diagrams suggest a continental rift setting and agree with the published sequence stratigraphic framework that suggests a deepening‐upward depositional trend associated with tectonic subsidence. This study documents geochemically the provenance of the sedimentary successions within the southern edge of the Sydney Basin and the continental rift origin of the basin. [ABSTRACT FROM AUTHOR]

The earliest record of Himalayan detritus in the Himalayan foreland and the erosion sequence of different lithotectonic units of the Himalaya are critical for reconstructing collision and crustal deformation of the orogenic belt. In this study, bulk‐rock major, trace and rare earth elements of 19 fine‐grained clastic sedimentary rock samples from Eocene to Pliocene strata of the Bengal Basin were examined to study their provenance and erosion of the Himalaya. Combining with previous detrital zircon age data from the Bengal Basin, Nepal foreland basin, and South Tibet, we suggest that detritus from the uplifted Tethyan Himalayan Sequences and the Gangdese Arc had not been carried into the Himalayan foreland at least before Late Miocene, and that the Bengal Basin was in a passive continental margin setting from Eocene to Early Miocene, receiving detritus from a felsic sedimentary rock source. The earliest Himalayan detritus recorded in the Eocene strata of Bengal Basin were probably derived from the antecedent sedimentary cover of the Greater Himalayan crystalline rocks. We assume that the lack of Cretaceous Gangdese detritus in the Himalayan foreland from Eocene to Middle Miocene is due to a geomorphic barrier between the Tethyan Himalaya and the Himalayan foreland. Detritus from the Greater Himalayan crystalline rocks were first recorded in the Middle–Late Miocene Boka Bil Formation of the Bengal Basin, which is consistent with the uplift and exhumation time of the Greater Himalayan Sequences. [ABSTRACT FROM AUTHOR]

As a record of oceanic subduction, an accretionary complex plays a key role in the reconstruction of plate tectonic history. The Kekesentao ophiolitic mélange between the Chinese Altai orogen to the north and the Kazakhstan collage to the south played an important role in the subduction–accretion of the Chinese Altai in the Palaeozoic. This article provides new structural field relations, and petrographic, geochemical, and geochronologic data for the Kekesentao ophiolitic mélange, and detrital zircon analyses of turbidites that are imbricated with the mélange. The Kekesentao mélange consists of ultramafic rocks, meta‐gabbros, pillow basalts, cherts, and imbricated trench turbidites, tuffaceous sandstones and quartz schists (ocean plate stratigraphy). The mélange shows a 'block in matrix' structure in the field, and the general imbricated dip of the thrust system is to the N‐NE, indicating southward accretion. Pillow basalts and meta‐gabbros have a typical N‐MORB geochemical signature, and the U–Pb zircon age of a meta‐gabbro, interpreted as the age of pre‐subduction oceanic crust, is Early Devonian (399–393 Ma). The upper time limit of accretion of the mélange is constrained by a Late Devonian (361 Ma) intrusive granitic pluton. Detrital zircon ages of surrounding turbidites range from 369 to 3,114 Ma, which is typical of magmatic 540–460 Ma zircons from the Chinese Altai, suggesting that the Chinese Altai arc was the source of zircons in the mélange. The Kekesentao ophiolite was accreted to the accretionary complex before the Late Devonian. Our analysis of structures, ocean plate stratigraphy, and zircon isotopic provenance of the Kekesentao ophiolitic mélange and turbidites provides a robust conclusion that southward growth of the accretionary complex in the Kekesentao area of the Chinese Altai was semi‐continuous from the Early Palaeozoic to Devonian. [ABSTRACT FROM AUTHOR]

Petrography and geochemistry of the Mesozoic sedimentary rocks of the Kutch Basin in western India reveal the predominance of felsic source rocks. Single‐grain chemistry of the detrital heavy minerals in these sediments refines the existing provenance interpretations by incorporating additional data related to source lithology. The study presents information on type, composition, and metamorphic grade of the source rocks for the Mesozoics of the Kutch Basin, which comprises Jhurio, Jhumara, Jhuran, and Bhuj formations. Chemistry of rutile, garnet, and tourmaline supports multiple sources of sediments. The ratio between Cr and Nb in rutile suggests the dominance of sediment input from metapelites. The relationship between (Fe + Mn)–Mg–Ca in garnets and Ca–Fetotal–Mg in tourmalines indicates the dominance of Ca‐poor felsic metamorphic source along with intermediate‐acidic plutonic rocks. The multivariate discrimination of the detrital garnets reveals the dominance of granulite and amphibolite facies source rocks. Rutile compositions indicate subordinate inputs from mafic sources across the investigated sedimentary succession. The single‐grain analysis of heavy minerals, therefore, infers a wide variation in source rock types. [ABSTRACT FROM AUTHOR]

The Late Palaeozoic dynamic setting of the Ordos Basin in the southwestern North China Craton (SW‐NCC) is poorly constrained due to limited understanding on the source‐to‐sink relation. This study presents integrated provenance clues from the Permian strata in the southwestern Ordos Basin to trace the sources and to discuss the tectonic setting of the basin in the SW‐NCC. The reconstructed palaeocurrent directions of these Permian sediments generally point to the northeast and suggest the dominant sedimentary influx from the southwest. Modal composition analysis shows the Permian deposits have an overwhelming derivation from mixed sources containing orogeny, continental block, and magmatic arc. Zircons from the lower section yield major age clusters of ~300–270 Ma and ~2,500–1,700 Ma. While, zircon age spectra for the upper section are marked by the abundance of ~1,000–800 Ma and ~500–400 Ma ages, and the lack of Permian populations. Sources of the lower section were interpreted to be the arc terrane along the southern border of SW‐NCC, in contrast, sources of the upper part were attributed to the Central Qilian Block. Zircons of ~300–270 Ma indicate significant magmatic activities in a rapidly uplifting continental arc, yielding an additional clue for the subduction and the existence of the Mianlue Ocean in the northeastern Palaeo‐Tethys. The changes in provenance and depositional rate at the Middle Permian indicate the rapid subsidence along with the intensive uplift of the continental basement in the SW‐NCC. These signatures likely infer that the back‐arc basin may have evolved into a compressional setting at that time. [ABSTRACT FROM AUTHOR]

Based on the clay mineral assemblages of 98 surface sediments from the lower Bengal Fan, we carried out a quantitative provenance identification and discussed the potential transport processes of fine fractions with the support of the hydrodynamic environment. Illite is the dominant clay mineral in the study area, with an average of 51%, followed by kaolinite, with an average of 20%, while chlorite and smectite account for averages of 17 and 11%, respectively. The study area can be divided into two provinces based on the clay mineral assemblages: Province I, located in the western part of the study area, has relatively higher smectite content, while province II, located in the eastern part, shows higher illite content. The Ganges–Brahmaputra (Himalayan) and the Godavari–Krishna (Indian Peninsula) are suggested to be the major provenances, and the average relative contributions of the Himalayan source and the Indian source are 76 and 24%, respectively. Sediments in province II receive more sediment from the Himalayan source, with an average contribution of 84%, while the Indian source mainly contributed to province I, with an average contribution rate of 32%. The Indian Peninsula materials are predominantly conveyed to the study area by the northeast monsoon circulation, and the relative contribution gradually decreases from northwest to southeast in the lower Bengal Fan. However, most of the Himalayan material is transported to the study area by the southwest monsoon. Our research indicates that the seasonal hydrodynamic pattern of the Northeast Indian Ocean plays an important role in controlling modern sediment transport in the Bay of Bengal, causing terrestrial materials from different sources to show significantly different spatial distribution characteristics. [ABSTRACT FROM AUTHOR]

Integrated petrographic studies entailing quartz‐type analysis and zircon typologic studies were carried out on sandstones of the Lower Devonian Accraian Formation of southern Ghana to constrain their provenance and tectonic setting. The stratigraphic succession of the Devonian Accraian Group consists mainly of sandstones in the Lower Accraian Formation, shales in the Middle Accraian Formation, and sandstone–shale intercalations in the Upper Accraian Formation. Systematic sampling of sandstones was conducted in the Lower Devonian Accraian Formation. Modal petrographic analysis indicates that the sandstones are quartz arenites with their framework grains consisting on average of, 99.8% quartz, 0.14% lithics with little or no feldspars. They are subangular to subrounded in shape. Modal mineralogy of the sandstones suggests that they are of craton interior origin with an affinity to recycled orogenic provenance. Quartz‐type analysis was used to unravel distinct characteristic features of the quartz grain, namely its polycrystallinity, nonundulose, and undulose nature to constrain the source rock. This pointed to multiple sediment supply from both a plutonic origin and a medium‐ to high‐grade metamorphic terrain. Furthermore, a comprehensive zircon typology study on 298 zircon grains indicate multiple provenances of calc‐alkaline affinity. This study revealed that the Lower Accraian Formation sandstones probably received sediment input from the Paleoproterozoic Birimian Basin granitoids and their associated metasedimentary rocks and some additional supply from the Neoproterozoic sedimentary rocks from the Volta Basin which are inclusive of sediments derived from the Dahomeyide Belt of the Pan‐African Orogeny. [ABSTRACT FROM AUTHOR]

It is well established that the Himalayan Orogen was formed by successive amalgamation of continental slices to the Eurasian continent, with the final collision of the Indian continent. The Upper Triassic Langjiexue Group on the north‐eastern margin of the Tethyan Himalaya has been central to debates on the provenance with diverse models linking it with the northern India, Lhasa terrane, or multiple sources from surrounding terranes including Australia. In order to address this debate, here, we present U–Pb ages, trace element characteristics, and Hf isotope data of detrital zircons. The trace element data suggest that analysed zircons are mostly of igneous origin, with a broad affinity to mafic source rock, and some of the grains showing evidence for hydrothermal alteration. The zircon age spectra show distinct Permian to Triassic age peaks at 200–280 Ma with εHf(t) between −6.1 and 13.4, Neoproterozoic to Cambrian ages at 480–750 Ma with εHf(t) ranging from −24.7 to 8.5, and a broad Meso‐ to Neoproterozoic age range of 850–1,150 Ma with εHf(t) values of −8.1 to 10.1. The age spectra from the Langjiexue Group are in contrast with that of the Lhasa terrane which has pronounced age peaks of 300–325, 550–600, 1,150–1,350, and 1,750–1,900 Ma, suggesting that Lhasa might not be the source of Langjiexue Group detritus. In a similar way, north‐western Australia and the Banda Arc are excluded as sources of the Langjiexue Group. The Hf model age spectra show distinct peaks of 750–800 and 1,200–1,300 Ma, and the second peak agrees with that of the Tethyan Himalaya. We infer that the basin of Langjiexue Group formed within the basement of Tethyan Himalaya in the Triassic and conclude that the sediments were deposited at the passive margin of northern Indian continent. Based on the results, we also propose the palaeogeographic evolution of the Himalayan Orogen. [ABSTRACT FROM AUTHOR]

We undertook an integrated approach incorporating whole‐rock geochemistry and detrital zircon U‐Pb geochronology from Permian sedimentary rocks in the Solonker area of central Inner Mongolia, China with the aim of constraining the tectonic evolution of the eastern segment of the Central Asian Orogenic Belt. Geochemical analysis reveals a close relationship between the sedimentary and volcanic rock suites in the study region. Detrital zircons from seven samples collected from the Zhesi Formation yield U‐Pb ages that cluster around 309–275 Ma and 464–435 Ma, with two main age peaks of ~452 and ~288 Ma. However, additional detrital zircons with ages in the range of 2,634–543 Ma are sparse and with no obvious age peaks. The results suggest that the deposition of the Zhesi Formation occurred from the Middle to the Late Permian and from two major age provenances: the Precambrian basement of the North China Plate (~1,880 Ma and ~2,520 Ma) and the Paleozoic Southern orogenic belt along the northern margin of North China (~288 Ma and ~452 Ma). In this contribution, we suggest that the Zhesi Formation in the Solonker area formed in response to the Early to Middle Permian subduction tectonic setting of the Paleo‐Asian Ocean (PAO), probably formed in a forearc basin and that the final closure of the PAO occurred after the Late Permian. [ABSTRACT FROM AUTHOR]

This study presents new detrital zircon laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) U–Pb ages and in situ Hf–O isotopic data in order to constrain the depositional age and provenance of the Benxi Formation in the Sanmenxia area of the southern North China Craton (NCC). Detrital zircons in quartz sandstone drillcore from the Benxi Formation are euhedral–subhedral, oscillatory zoned, and have high Th/U ratios (0.03–1.60, generally greater than 0.3) that are indicative of a magmatic origin. Detrital zircons from samples 13H16A and 13H16B yield seven (2544, 1788, 1123, 955, 737, 441, and 344 Ma) and six main age populations (2440, 1583, 951, 759, 434, and 348 Ma), respectively. The εHf(t) values of the Neoarchean–Paleoproterozoic zircons range from −11.3 to +13.9, and these zircons have δ18O values that range from 5.68‰ to 8.83‰. The Neoproterozoic zircons have variable εHf(t) (−9.2 to +12.5) and δ18O (5.58‰ to 9.85‰) values, whereas the Palaeozoic zircons have εHf(t) values between −19.9 and +13.4 and δ18O values of 5.23‰–9.43‰. The Benxi Formation was deposited during the late Carboniferous and contains sediments derived from igneous rocks of the North Qinling Orogen combined with a small amount of material derived from Precambrian basement of the NCC. The northward subduction of the South Qinling Orogen caused the uplift and erosion of the North Qinling Orogen during the late Carboniferous. [ABSTRACT FROM AUTHOR]

The Solonker Suture Zone was formed during the closure process of the Paleo‐Asian Ocean (PAO). In order to better constrain its tectonic setting and evolution history in the Late Carboniferous–Early Permian, we conducted an integrated study of the Shoushangou Formation in the central Inner Mongolia, involving the sedimentological features, depositional age, and detrital zircon populations. Our results indicate that the Shoushangou Formation was deposited in ca. 320–280 Ma, overlain by the Dashizhai Formation with ages of ca. 280–274 Ma, and the 330‐ to 280‐Ma detrital age data almost serve as the entire age component of this formation. Also, its stratigraphic reconstruction shows a coarsening‐upward marine sequence upwards, which is characterized by sandstone turbidites with a Bouma sequence and the numerous tuff involvements in the lower strata, showing a deep marine environment and synchronous volcanism. Integrating previous data and our results, with a gradually deepening water depth and a geographic variation, detrital zircon age spectra from the Late Carboniferous–Early Permian sequence show distinct differences, and a marked shift of multiple resources to a single source occurred in the Late Carboniferous–Early Permian. These clues suggest an active marginal setting and a northward‐dipping subduction during this period in the north side of the PAO, and we further attribute such a source variation to the spreading of a marine back‐arc basin after the amalgamation of the Uliastai Active Continental Margin with the Northern Accretionary Orogen. The Shoushangou Formation was the direct depositional response to such a back‐arc basin. [ABSTRACT FROM AUTHOR]

The palaeogeographic and tectonic setting of the Lower Jurassic Nishinakayama Formation (Toyora Group, southwest Japan) is interpreted based on new U–Pb ages for detrital zircon grains separated from a sandstone sample, combined with available provenance data. The newly obtained age spectrum of detrital zircon grains is characterized by multiple age clusters. Specifically, (1) nearly syndepositional (Lower Jurassic; 182–200 Ma), (2) Early Permian to Late Triassic (205–288 Ma), and (3) Precambrian (1,855–2,660 Ma). The youngest zircon age (182.4 ± 5.1 Ma) is consistent with the biostratigraphically constrained depositional age (falciferum ammonite Zone, lower Toarcian). The presence of a near‐syndepositional age cluster, as well as the presence of volcanic tuff layers in the studied succession, indicates the likely extensive influence of an active volcanic arc in the depositional area. The age cluster of 205–288 Ma suggests, in contrast, that older granitic batholiths were also being sourced. Precambrian detrital zircon grains would have been derived from continental blocks with mainly Proterozoic crusts, most likely from the North China Craton. When combined with available geochemical, petrological, and palaeontological data, our detrital zircon data demonstrate that deposition of the Nishinakayama Formation was located at an active continental margin, possibly close to the northern extremity of the South China Craton. Abundant terrigenous clastics were likely supplied to the sedimentary basin from the Qinling‐Dabieshan‐Sulu Suture Zone, which was formed by the collision of the North and South China cratons. [ABSTRACT FROM AUTHOR]

The Upper Devonian Shetianqiao Formation mudstones are considered to be the most petroliferous shale gas source rocks in the Shaoyang Sag of Xiangzhong Depression in China. These Shetianqiao dark mudstones have been collected systematically to investigate their geochemical characteristics by analysing their major elements, trace elements, and rare earth elements (REEs), in order to reveal their provenance, palaeoenvironment and tectonic setting. The results show that the total REEs content (ΣREE) of dark mudstone is 34.22–246.62 ppm (average 131.66 ppm) and characterized by low ΣREE, light rare earth element (LREE) enrichments, negative Eu anomalies, and minor negative Ce anomalies. The normalized distribution pattern of REE, Eu anomaly, as well as discrimination diagrams of trace elements and REEs, are applied to explain the source rock types and properties of Shetianqiao mudstones. The results indicate that the sediments have a weak sedimentary recycling and mainly originated from the upper continental crust, and the source rocks of the black mudstones are mainly constituted by felsic granite. The Ce anomaly, Th/U, V/Sc, V/Cr, and V/(Ni + V) ratios of the dark mudstones suggest a long‐term oxidizing depositional environment interrupted by a short period of a dysoxic/anoxic depositional environment in the middle section of the formation. This short period corresponds to a dramatic marine transgression with relatively high TOC. The La/Ce, LaN/SmN, Ce anomaly, and normalized REE distribution pattern characteristics indicate that the depositional process of the Shetianqiao mudstones has consistently been influenced by the regional upwelling hydrothermal activities. The chemical index of alteration (CIA) and Al2O3‐(CaO* + Na2O)‐K2O triangular plot reveal that a warm and humid climate with moderate chemical weathering in the source areas of the Shetianqiao mudstones occurred during the deposition. The ratio of major elements, trace elements, and REEs are used to analyse the tectonic setting of the depositional area which suggests that the source area is dominated by continental island arc tectonic setting. Combined with the previous regional studies, it is concluded that the continental island arc granite formed by plate collisions in the Caledonian stage constitutes the main source of the Shaoyang Sag during the Shetianqiao period. The depositional environment was not stable due to the lasting influence of deep hydrothermal activities. The upwelling currents controlled by hydrothermal activity transport nutrients to the study area, resulting in the formation of organic‐rich mudstones. [ABSTRACT FROM AUTHOR]

The metasedimentary rocks of the Sefwi and Lawra volcanic belts in Ghana respectively were analysed for their major and trace elements and Sr‐Nd isotopic compositions to constrain the provenance, palaeo‐weathering conditions, and tectonic setting of the rocks. Geochemical characteristics of the metasedimentary rocks show low to moderate chemical weathering in their source regions and the rocks are interpreted to have been derived from mixture of mafic and felsic rock components. The LREE show much enrichment in relation to the HREE (LaN/LuN, 4.67‐11.66). The εNd (2.1 Ga) values of −0.12 to +3.72 strongly suggest that the source of the sedimentary rocks was derived from a depleted mantle source and that they were most likely produced in an almost entirely oceanic environment with minor influence from the continental crust. The Nd model ages ranging from +2.05 to 2.41 Ga suggest possible contributions of a pre‐Birimian crustal material (or Archaean?) in the source material of the volcanic rocks. The rock types that contributed as detritus to the Birimian metasedimentary rocks were mainly pyroclastics and basalts, and their REE patterns suggest that the contribution to the phyllites can be modelled after 20% basalt, 13% andesite, and 67% dacite. Similarly, the schists can be modelled as a mixture of 16% basalt, 34% andesite, and 50% dacite. The Nd isotopic modeling implies that the bulk of the sedimentary detritus was supplied by the Palaeoproterozoic volcanic arc with contributions of less than 10% from the pre‐Birimian crust (Archaean?). [ABSTRACT FROM AUTHOR]

Basin formation and sedimentary development in the southern North China Craton (NCC) are closely related to the tectonic evolution of the Qinling Orogenic Belt (QOB). With the aim of revealing the coupling evolution between the QOB and southern NCC during the Late Palaeozoic, an investigation based on provenance analysis was performed in this study. We present new detrital zircon U–Pb data from the Middle–Late Permian sediments in the Yiyang area, southern NCC. The results show that detrital zircons, from the Middle Permian Shihezi Formation, have three major peaks at 2,447, 1,905, and 296 Ma. In contrast, the lower and upper parts of the Late Permian Sunjiagou Formation yield major peaks at ~1.85 Ga and ~260 Ma, with weak peaks at ~2.5 Ga, ~450 Ma, and ~315 Ma, and the middle part of the Sunjiagou Formation displays a major peak at 429 Ma. Combined with published palaeocurrent data and lithofacies palaeogeography, the sediments of the Middle Permian Shihezi Formation were sourced from the Inner Mongolia Palaeo‐Uplift along the northern margin of the NCC, whereas the Upper Permian Sunjiagou Formation originated mainly from the southern margin of the NCC including the North Qinling Belt. This provenance shift indicates that the North Qinling Belt and southern margin of the NCC initiated the uplift and exhumation during the Late Permian. On the basis of the evolutionary history of the QOB, we attribute the uplift geodynamics to the Mianlue oceanic crust subduction. This study provides important sedimentological constraints for the tectonic conversion during the Late Palaeozoic along the southern margin of the NCC, which also restricts the start‐up time of the Mianlue oceanic crust subduction from the perspective of the basin–mountain system. [ABSTRACT FROM AUTHOR]

The northwestern part of Mexico, southern Arizona, and southern California witnessed extensive arc magmatism during Late Triassic to Early Cretaceous. Here, we present results from petrography, whole‐rock geochemistry (major and trace including rare‐earth elements), and detrital zircon geochronological studies that were carried out on sandstones and shales of the Mural Limestone exposed in the Rancho Bufalo area. Based on the petrography, sandstones are classified as sublitharenite, litharenite, feldspathic litharenite, and lithic arkose. The sandstones contain higher proportion of monocrystalline quartz than polycrystalline quartz. Sandstones and shales from the various members of the Mural Limestone show large variations in major and trace elements concentrations. The average concentrations of ΣREE (total ΣREE) are lower in sandstones than in shales. The chondrite‐normalized REE patterns of the sandstones and shales are moderately fractionated with light REE (LREE) enrichment relative to heavy REE (HREE) and with flat to slightly depleted HREE patterns. The chemical index of alteration values and A–CN–K relationships of sandstones indicate low to moderate intensity of weathering in the source region; however, shale samples suggesting the source rocks were subjected to moderate intensity of chemical weathering. The chondrite‐normalized REE patterns, Al2O3/TiO2 ratio, elemental ratios like Cr/V, Y/Ni, and Eu‐anomaly (Eu/Eu*), and bivariate plots suggest that the sandstones and shales were derived mainly from felsic source rocks. Detrital zircon U–Pb geochronology of sandstones from Fronteras, Rancho Bufalo, and Cerro La Ceja members of the Mural Limestone show five main groups of detrital zircon age populations: (a) Proterozoic, (b) Palaeozoic, (c) Triassic, (d) Jurassic, and (e) Early Cretaceous. Our study suggests that continental volcanic arcs in northwestern Mexico, southern Arizona, and southern California served as the provenance for the Late Triassic‐Jurassic detritus, whereas the Early Cretaceous zircon grains were derived mainly from the active Alisitos volcanic arc along the northwestern coast of Mexico. [ABSTRACT FROM AUTHOR]

The North Qilian Orogenic Belt (NQOB) is an important element of the northern edge of the Tibetan Plateau, and several rivers run along it. Zircon U–Pb dating, trace elements, and Hf isotopic data derived from the sediments carried by the rivers have been used to deduce the crustal evolution of the NQOB. U–Pb ages obtained from detrital zircons found in the sediments of the Zamu, Zhuanglan, and Beida rivers can be divided into five major age groups, that is, 2,600–1,500, 1,500–1,100, 1,100–650, 550–400, and 360–150 Ma, and the corresponding peaks occur at ~2,450, ~1,750, ~950, ~450, and ~250 Ma. Archean components, which may be derived from the ancient continental nucleus in the region, are rare in the river sediments. The zircon grains with ages of 360–150 Ma are most likely related to crustal thickening and decompression melting in a post‐collisional tectonic setting. The age distribution patterns indicate that the sediments carried by the Zamu, Zhuanglang, and Beida rivers are derived from the NQOB. Furthermore, the Hf isotopic compositions of Meso‐ and Neoarchean, Mesoproterozoic, Grenvillian, Pan‐African, Caledonian, and Hercynian zircon age groups exhibit a wide range of εHf (t) values, suggesting diverse sources. The existence of strongly negative εHf (t) values among the Grenvillian and Paleoproterozoic zircons indicates that the source magma included reworked Palaeoarchean crustal materials. New results indicate that continental rifting and the opening of the Qilian Ocean occurred at 775–520 Ma; the subduction and closure of the Qilian Ocean occurred at 520–440 Ma; arc–continent collision and continental subduction occurred at 440–420 Ma; and orogen collapse and extension occurred at 400–360 Ma. Our study indicates that the formation of the NQOB was mainly related to the evolutionary history of the Proto‐Tethys Ocean. [ABSTRACT FROM AUTHOR]