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[Display omitted] • Increasing demand for Ni in the clean energy transition has identified Ni as a critical metal. • Ni provides high storage capacity, which reduces the size of lithium ion-batteries. • High-grade Ni laterites and sulfide deposits are depleting due to intensive production and overconsumption. • Exploitation of low-grade Ni sources such as serpentine soil will contribute to maintain a sustainable supply in future. • Phytomining is a potential route for economic exploitation of Ni from low-grade sources. In 2022, nickel (Ni) was nominated as a critical metal due to its wide applications in the metal industry, especially in clean energy applications to achieve climate mitigation targets. Meantime, rapid industrialization and escalating demand for electronic battery manufacturing have increased global Ni consumption, and therefore available primary Ni resources will not be sufficient to cater to the demand. As a result, currently, the Ni supply chain is diversifying focusing on low-grade Ni resources which were previously considered as economically invaluable. This paper presents comprehensive study on different applications of Ni, existing high-grade Ni resources, mode of occurrence, and the production and future demand of Ni, and discusses the state of art on the different leaching and extraction methods to recover Ni from low-grade sources, such as mine tailings, galvanic sludge, electronic batteries, and serpentine soil. In addition, this paper highlights the current status of the Ni phytomining approaches in serpentine soil and its future perspectives. It is evident that a development of Ni phytomining industry as a carbon–neutral mining technique is essential to overcome Ni supply risk for the commercial production of Ni using low-grade resources. Finally, this study will evaluate the production of high-quality Ni from low-grade secondary sources. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Halazha pluton is composed of 244 Ma quartz diorites and intruded 233 Ma granodiorites, both containing coeval MMEs. • The formation of MMEs involves two stages of magma mingling. • The Halazha pluton is derived from the partial melting of the juvenile crust. • Amphibole cumulates can contribute to the formation of quartz diorites. Granitoids and coeval mafic microgranular enclaves (MMEs) provide important insights into petrogenesis and crustal evolution. In the eastern sector of the East Kunlun Orogen, the Halazha (HLZ) pluton contains abundant MMEs, recording magma mingling processes. The HLZ pluton comprises quartz diorites and granodiorites, whereas the MMEs have a gabbroic-dioritic composition. This paper provides a detailed description of the petrography and mineralogy of the HLZ pluton and MMEs, and presents new ages and geochemical data. The zircon U–Pb dating results indicate that quartz diorites and granodiorites are ranging from 243 ± 2 Ma to 244.8 ± 1.3 Ma and from 233.3 ± 1.1 Ma to 233.6 ± 1.5 Ma, respectively. The zircon ages of the coeval MMEs are identical to the host rocks, i.e., 244.5 ± 1.1 Ma − 244.5 ± 1.2 Ma, and 233.7 ± 1.3 Ma, respectively. Both quartz diorites and granodiorites contain hornblende, display metaluminous characteristics with average A/CNK values of 0.93 and 0.99, respectively, and thus belong to I-type granite. Both of them are enriched in large-ion lithophile elements such as Rb and Ba and depleted in high-field-strength elements such as Nb and Ta. In addition, they both have low ε Hf (t) values, ranging from −5.6 to −1.7 and −5.4 to −1.79, respectively. Results suggest that HLZ pluton is derived from magmas formed by the partially melting juvenile mafic lower crust. Quartz diorites experienced hornblende accumulation for its low SiO 2 contents. Whereas, the high Sr/Y ratio of granodiorites attributes to the fractional crystallization of apatite. Notably, the crystallization pressure and temperature (average 3.43 kbar and 764 °C) of the hornblende xenocrysts in MMEs is close to it of the hornblende phenocryst in quartz diorite (average 3.68 kbar and 766 °C). This similarity indicates that MMEs in the quartz diorites resulted from magmatic mingling between the mafic magma and the host rock within the deep crust. The hornblende xenocrysts present in MMEs of the granodiorites contain a higher number of inclusions, reveal higher crystallization pressures (average 2.73 kbar) and temperatures (average 825 °C) compared to their host rocks (average 1.35 kbar and 702 °C). These results suggest that MMEs in granodiorites underwent two distinct magmatic mixing processes: the magmatic mixing of mafic magma in the deep crust and then during the upwelling process after this mixed mafic magma entered the granodiorites. [ABSTRACT FROM AUTHOR]

During the Early Permian, the Kazakhstan-Junggar Block collided with the Siberian Craton, while the Chinese Altai entered a stage of syn- to post-collision evolution. In this period, a large-scale intrusion of mantle-derived magma provided the necessary heat to initiate intense interaction between the crust and mantle, leading to the formation of the W-mineralized Bastielieke granitic pluton. [Display omitted] • The Bastielieke granitic pluton formed at 278–270 Ma in a syn- to post-collision setting. • The granitic pluton was derived from crusal recycling of sedimentary rocks. • There is a genetic link between the granitic pluton and W deposit in Bastielieke. Granitic magmatism of the Altai orogen is the key to understanding the tectonic evolution and metallogeny in the Central Asian Orogenic Belt (COAB). In this paper, we conducted comprehensive petrological, geochronological and geochemical investigations on the Bastielieke granitic pluton in the Altai orogen. Zircon U–Pb dating shows an emplacement age of 278–270 Ma for the pluton. Granites of the Bastielieke pluton have S-type granitic affinity and have Zr + Nb + Ce + Y contents (76.6–272 ppm), A/CNK ratios > 1.1, and K 2 O > Na 2 O. The low ε Nd (t) (−2.8 to + 2.9) and high ε Hf (t) (+7.6 to + 15.9) values with Nd-Hf isotope decoupling, invariable Pb isotopes, and moderate zircon δ18O V-SMOW values suggest crustal recycling of sedimentary rocks in a syn- to post-collision setting. In addition, the pluton is spatially related to the tungsten (W) deposit and also temporally consistent with the mineralization age of 284 ± 6 Ma, indicating a genetic link between the Early Permian magmatism and mineralization in Bastielieke. Furthermore, the source rocks of the pluton which are sedimentary rocks and abundant in W, provide the material basis for the initial enrichment of W in primary magmas. Given high Rb/Sr (>3) and low K/Rb ratios (<2 0 0), we interpret that the pluton has experienced high differentiation. Our studies propose that the termination of the subduction-accretion of the Paleo-Asian Ocean and the initiation of a syn- to post-collision regime for the Altai orogen are probably at the Early Permian. [ABSTRACT FROM AUTHOR]

• Identification of the Suolong Cu-rich porphyry is suggestive of a new mineralization event. • The porphyry was generated from crust-mantle interactions during the roll-back of subducted NTO. • The features of magma promoted the enrichment of Cu, but thinned crust limited the scale of deposit. The Tibetan Plateau hosts the majority of porphyry Cu deposits in China. There are two large metallogenic belts, the Gangdese and Bangong-Nujiang belts, in the Lhasa Terrane, Central Tibet. The Lhasa Terrane experienced multistage magmatic activity from the Mesozoic to Cenozoic, and the subaerial volcanic areas of the western part of the terrane are regarded as favorable targets of porphyry Cu deposits. In this paper, we describe the geology of our newly identified Early Cretaceous Suolong Cu-rich porphyry in the western Lhasa Terrane and present new U–Pb ages, trace element and Hf isotopic compositions of zircon and whole-rock elemental and Sr–Nd isotopic compositions. The Suolong porphyry contains zircon grains with ages ranging from 136 to 135 Ma, ε Hf (t) values ranging from −1.5 ∼ +2.7 and log f O 2 values ranging from −16.27 ∼ −9.92. Geochemically, the porphyry rocks are peraluminous in nature, with whole-rock ε Nd (t) values of −5.7 ∼ −5.4. We infer that the Suolong porphyry originated from a mixture of ∼53 % enriched lithospheric mantle and ∼47 % ancient lower crustal melt, triggered by the roll-back of the northward-subducting Neo-Tethyan Ocean. The conditions of high oxygen fugacity and water content and tectonic transition promoted the formation of the Suolong Cu-rich porphyry, but the condition of a thinned crust may have constrained the mineralization scale of the Cu deposits. This new identification of Early Cretaceous mineralization event provides important clues for identifying new potential exploration targets for porphyry Cu deposits in the western segment of the Lhasa Terrane. [ABSTRACT FROM AUTHOR]

• Two phases of deformation occured in the south of the Shangdan suture zone across the Mianyuzui ductile strike-slip fault. • The metamorphic temperature of the early stage of shearing deformation is ∼ 600-700℃ and ∼ 300-500℃ for the late stage. • The subduction of the Shangdan Oceanic lithosphere was active till the Early Silurian, and subsequent collisions occurred during the Late Silurian. The Shangdan suture zone (SDSZ) subdivides the Qinling Orogenic Belt into North Qinling and South Qinling belts, marking the main tectonic boundary between the North China and South China Blocks. The Mianyuzi ductile strike-slip fault (MYZF) within the SDSZ separates the North China Block from the South China Block and contains valuable collisional information. This paper integrates the structural and geochronological data of the MYZF to investigate the Paleozoic tectonic evolution of the Qinling Orogenic Belt and the collision between the North China and South China Blocks. Two phases of deformation (D 1 -D 2a-b) are identified along the southern boundary of the SDSZ. The metamorphic temperature of mylonites is ∼ 600–700 ℃ for the early stage and ∼ 300–500 ℃ for the late stage of shearing deformation. U-Pb zircon analysis of the mylonites and diabase dike in the ductile shear reveals that zircons have major younger protolith populations at 480–460 Ma, 450–430 Ma, and 405–425 Ma, which suggests that rocks were probably derived from the North Qinling belt. The metamorphism and deformation cooling age from the MYZF have been constrained to be 339–328 Ma and 259 ± 1.6 Ma using U-Pb and 40Ar/39Ar dating. Combined with previously published data, we concluded that the subduction of the Shangdan Ocean was active until the Early Silurian and subsequent collisions occurred during the Late Silurian. Meanwhile, the shearing might have been related to the intraplate extension-exhumation during the Carboniferous-Late Permian in the Qinling Orogenic Belt. [ABSTRACT FROM AUTHOR]

• Sand wedge deposits were identified in the Early Miocene Wuqia Group. • Sand wedges occurred in braided fluvial environment under arid and cold climate. • The northern Tibetan Plateau surpassed 1000 m elevation in the Early Miocene. The uplift of the Tibet Plateau and its climatic effects have long been a hot topic in academic research. However, there is still significant controversy regarding the uplift history and related climate changes along the northern margin of the plateau. In this paper, we present sand wedge deposits from the base of the Wuqia Group (∼20 Ma) on the southwestern Tarim Basin, representing the oldest reported sand wedges in the Tibetan Plateau. A comprehensive study was conducted on lithostratigraphy, sedimentary environment, and macroscopic–microscopic features of the sand wedge deposits. The results indicate that the lithostratigraphic succession preserving the sand wedge deposits consists mainly of lenticular conglomerates and cross-bedded gravelly sandstone interbedded with medium–thin-bedded mudstone, consistent with the braided fluvial environment. The sand wedge deposits commonly exhibit a V-shape geometry and are filled with gravelly sandstone, with the gravels arranged parallel to the walls of the wedge. The clasts of the wedge-filled sandstone are well-rounded and show a unimodal grain size distribution. The quartz surfaces commonly display dish-shaped and crescent-shaped impact features, indicating an eolian origin and an arid climate. Based on the relationship between the formation temperature of modern sand wedges, the atmospheric temperature gradient, and altitude, the reconstructed paleo-elevation of the sand wedge deposits at the base of the Wuqia Group in the southwestern Tarim Basin is approximately ∼ 1000 m. These results indicate that the northern margin of the Tibet Plateau had already reached an elevation of ∼ 1000 m during the Early Miocene, forming a seasonal arid and cold climate. [ABSTRACT FROM AUTHOR]

• The 210–205 Ma Habake pluton was formed in a continental collision setting. • The final closure of the Paleo-Tethys in the West Kunlun orogenic belt occurred after 209 Ma. • The parent rocks of rare metal-mineralized pegmatites are all S-type granites and contain >150 ppm Li. Recent discoveries of rare metal pegmatite deposits in the West Kunlun region are believed to be related to Triassic granites. However, the tectonic background of the mineralization in this region is currently unclear. Additionally, the mineralization potential of the granite must be determined to assess whether further exploration is warranted. This paper reports whole-rock elemental and Sr-Nd isotopic compositions, and zircon U-Pb ages and Lu-Hf isotopic compositions for the Habake granitic pluton. The zircon U–Pb dating revealed that these rocks formed in the Late Triassic (210–205 Ma). The two-mica granites are strongly peraluminous high-K calc-alkaline series rocks, with initial 87Sr/86Sr ratios of 0.71294 ∼ 0.71428, εNd(t) values of −7.79 ∼ -8.15, and εHf(t) values of −1.77 ∼ −32.22; these values are similar to those of Triassic BaryanHar Group graywacke rocks. The other granites are weakly peraluminous high-K calc-alkaline series rocks, with initial 87Sr/86Sr ratios of 0.70820 ∼ 0.70823 and 0.70942 ∼ 0.71041, εNd(t) of −3.81 ∼ -4.11 and −5.33 ∼ -5.40, and εHf(t) of −0.90 to +7.02 and −1.39 to −7.68, indicating that the granodiorite and biotite granite were respectively derived from partial melting of the juvenile crust and older lower crust in continental collision stage. Our new data show that the end of the continental collision between the South Kunlun Terrane (SKT) and Tianshuihai terrane (TST) likely occurred after 209 Ma. After analysis of the ore-forming parent rocks of the rare metal pegmatites, the graywacke-derived Habake two-mica granites, has lower Li contents that too low(<150 ppm), indicating that they did not form the rare metal pegmatites. [ABSTRACT FROM AUTHOR]

• High-carbon silty dolomite is the most favorable exploration target for shale oil in Lucaogou Formation of Jimsar Sag. • TOC, microscopic pore-throat structure, and pore types are the key factors controlling the movable oil content of different lithofacies. • A new Conceptual model is given to illustrate multi-scale linkage between lithofacies, pore structure, and fluid occurrence. The heterogeneity of lithofacies is a pivotal factor influencing the shale oil potential. A comprehensive understanding of the intricate influence of rock complexity on hydrocarbon generation properties, microscopic pore-throat structure, and fluid occurrences is crucial for shale oil exploration and development. The Lucaogou Formation in the Jimsar Sag is a type of saline lacustrine shale oil, which was chosen as a research example in this paper. To unravel the causal linkage and confirm the coupling relationship between lithofacies, pores, and fluid mobility in the sedimentary sequence of saline lacustrine basins, a series of experiments were conducted. These included total organic carbon (TOC), X-ray diffraction (XRD), vitrinite reflectance (R o), Rock-Eval pyrolysis, field emission-scanning electron microscopy (FE-SEM), low-field nuclear magnetic resonance (LF-NMR), mercury intrusion porosimetry (MIP), and low-temperature nitrogen adsorption (LTN 2 A). The results revealed significant differences in pores, oiliness, and fluid mobility among the four dominant lithofacies. Employing an innovative comprehensive evaluation method, high-carbon silty dolomite manifests significant potential for hydrocarbon generation, substantial storage capacity, effective oiliness and mobility , heightened brittle mineral content, and facile fracture production. Consequently, it was the most favorable lithofacies. Furthermore, TOC, pore size, and pore types emerged as key factors influencing the movable oil content of different lithofacies. More importantly, a detailed multiscale model illustrated potential linkages across the three different scales of lithofacies associations, pores, and fluid mobility. The study's outcomes can offer enhanced guidance for accurately assessing shale oil resources, particularly in the identification of crucial "sweet spots". [ABSTRACT FROM AUTHOR]

The Qiangtang Basin is one of the largest Mesozoic petroliferous basins in China that is still unexploited for the petroleum industry. The basic geological issues and synthesis of the Qiangtang Basin related to the Tethyan evolution are still poorly understood. This volume presents 20 research papers to address the tectonic settings, basin evolution, and sedimentary environments of the Qiangtang Basin, which are key factors for a better understanding of the overall petroleum system. The Qiangtang Basin holds a Precambrian base developed in response to the Paleo-Tethys Hol Xil-Jinshajiang Ocean evolution, with enhanced sedimentary basin infilling during the opening and expansion of the Neo-Tethys Bangong-Nujiang Ocean in the Mesozoic. The Paleozoic basin framework of the Qiangtang demised as the Paleo-Tethys Ocean closed at the latest Permian, while the Early-Middle Triassic foreland basin underwent a negative basin inversion during the Late Triassic. The latter initiated a new sedimentary filling cycle of the Qiangtang Basin, which was triggered by the active extensional rifting and the onset of the bimodal volcanic eruption. Recent scientific exploratory drilling (QK-1 well) found that the Qiangtang Basin is characterized by multiple source rocks, of which the upper Triassic Bagong Formation and the lower Quse Formation exhibit the most hydrocarbon generation potential. The development of high quality and quantity source rocks in the Qiangtang Basin is ensured by regional to global-scale bottom-water anoxia and high primary productivity in the eastern Tethys realm in the Late Triassic and the Early Jurassic. The main reservoirs in the Qiangtang Basin include the Middle Jurassic reef-beach facies, the Upper Triassic carbonates, and the Lower Jurassic terrestrial clastic rocks. Two very-thick caprocks of gypsum in the Lower Jurassic and gypsum mudstones in the Middle Jurassic strata are found during the scientific drilling, which is interpreted as favorable regional-scale seals for petroleum entrapment in the Qiangtang Basin. [ABSTRACT FROM AUTHOR]

[Display omitted] • The age of Neogene sedimentary rock in the basin spans the interval of 13.61-2.58Ma. • The Neogene strata are divided into the Xianshuihe Fm. and Linxia Fm. • The growth of the Tibetan Plateau initiated at ca. 8.11 Ma in the Laolongwan Basin. The Laolongwan Basin, located on the northeastern margin of the Tibetan Plateau, has a thick layer of Neogene red sediments deposited, recording the northeastward growth process of the Tibetan Plateau. However, due to the lack of high-precision chronology of the late Cenozoic sediments in the basin, the understanding of the growth process of the northeastern margin of the Tibetan Plateau is limited. Based on regional geological surveys, this paper presents a high-precision paleomagnetic stratigraphic chronology study on the Neogene strata of the basin, and establishes a chronological framework for the Laolongwan Basin spanning from ∼ 13.61 Ma to 2.58 Ma. Integrating the paleomagnetic chronological framework with regional geological survey results, the Neogene sedimentary rocks of the Laolongwan Basin are divided into the late Miocene Xianshuihe Formation (∼13.61–8.11 Ma) and the late Miocene to late Pliocene Linxia Formation (8.11–2.58 Ma). Combined with high-precision measured stratigraphic sections, our work indicates a significant change in sedimentary facies at ca. 8.11 Ma, transitioning from siltstone and mudstone deposition to conglomerate deposition, and the sedimentation rate increased remarkably from 256 m/Myr to 544.8 m/Myr, indicating that the northeastward expansion of the Tibetan Plateau affected the Laolongwan Basin at ca. 8.11 Ma. [ABSTRACT FROM AUTHOR]

• The steepest sidewall (with slopes of 25.75° and 40.47°) of E Canyon in the eastern Makran accretionary prism was found. • The segmentation features of sedimentation and erosion of E Canyon was revealed. • The evolution model of gas hydrate accumulation in the development area of E Canyon was established. Seven shelf-incising submarine canyon systems are developed in the Makran accretionary prism, offshore Pakistan. This paper uses multibeam bathymetric data and multichannel seismic profiles to study the geomorphologic and infilling characteristics of E Canyon in the east of accretionary prism. The E Canyon extends nearly north–south from the upper slope to lower slope, the bottom of the canyon is located in 1000 to 3000 m water depth, the main axis extends about 55 km, and the width varies from 5 to 9 km. The E Canyon shows U-shaped concave features in the northern cross-section view and V-shaped concave features in the southern cross-section view. Two continuous erosion pools are developed at the fifth and third ridges of the southern segment, respectively. The steepest sidewall (with slopes of 25.75° and 40.47°) of E Canyon was found near the third ridge. The filling sequence of coarse channel lags, slump debris flows, stacked channel sands and mass transported deposits and turbidite deposits from bottom to top is developed in the northern segment of the canyon. Strong erosion is developed in the southern part of the canyon and there is no sedimentation inside. On the abyssal plain, the continuation of the E Canyon is clearly erosive. Our preliminary analysis shows that the factors controlling the evolution of E Canyon may include sediment gravity flow, tectonic activity, sea-level change, climate and onshore rivers activity. The correlation between evolution of E Canyon and gas hydrates was explored, and it is believed that the erosion of E Canyon plays a destructive role in hydrate accumulation. At the same time, the destruction of hydrate-bearing layer induces the escape and leakage of hydrocarbon-bearing fluid, leading to the development of pockmark on the sidewalls of E Canyon. And the evolution model of gas hydrate accumulation in the development area of E Canyon was established. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au, Ag, Te in pyrite of the auriferous veins occur in micron-sized mineral inclusions. • Te melt is a key scavenger of Au from ore-forming fluids in the Yangwuchang deposit. • The ore-forming metals should be derived from a W-Au-rich magma system. • It has great W exploration potential at the deep part of magmatic type Au deposits. The co-mineralization of W and Au in some deposits has long been noted, yet remains debated. The Yangwuchang W-Au deposit provides an excellent opportunity for examining the genetic relationship between the mineralization of these two elements. In this paper, we present new trace elemental data for pyrite and sulfur isotopic compositions for sulfide minerals to better understand the co-mineralization of W and Au. Type 1 pyrite (Py1) is mainly hosted in the W-bearing veins and has low concentrations of Au (0.01–0.04 ppm), Ag (0.06–437 ppm), and Te (1.77–234 ppm). In contrast, type 2 Pyrite (Py2) in the auriferous veins is relatively enriched in Au (0.06–209 ppm), Ag (0.44–58610 ppm), Te (1.88–42337 ppm), and other trace elements. The concentration of Au has a positive relationship with Te but not with As, suggesting Te melt plays a significant role in scavenging Au from ore-forming fluids during mineralization. The narrow range of δ34S value (-3.17 to 3.69 ‰), combined with high Te contents and Co/Ni ratios of pyrite, indicates that the ore-forming metals may have been derived from a W-Au-rich magma. The slight negative values of δ34S in Py1 infer the localized pressure fluctuations during W mineralization. We concluded the W and Au could be both derived from one single magma system. The deep part of Au-bearing veins has great exploration potential for W mineralization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The activity of depression-controlling fault controlled source rock thickness and distribution. • The preservation environment and organic matter supply controlled the quality of source rocks. • The accumulation mechanism of source rocks changed with tectonic activity and climate evolution. Lacustrine source rocks have a significant oil potential and contribute to 95 % of oil reserves in China's offshore areas, Nature of these rocks is related to climate and structure and they are commonly heterogeneous. Mechanism of organic matter accumulation in these rocks has been a matter of debate. Based on Rock-Eval pyrolysis, organic petrographic examinations, gas chromatography-mass spectrometry (GC–MS) analysis, and trace elements analysis, this paper illustrates the paleoclimate, tectonic activity, paleo-productivity, and preservation conditions recorded in high-quality source rocks of the Shanan Sag. The aim is to understand the controlling factors on the deposition of these source rocks. The results indicated that the organic matter of source rocks in middle segment of the third member of the Shahejie Formation (Es 3 m) was mainly from phytoplankton (average content = 52.2 %), the development of source rocks was controlled by high paleo-productivity. The primary productivity was low during the period of the first and second members of the Shahejie Formation (Es 1-2), and the high gammacerane index, and low Pr/Ph ratios indicated that the source rocks were mostly controlled by a good reduction environment with high salinity. The source rocks of the third member of the Dongying Formation (Ed 3) were characterized by high terrestrial materials (average exinite content = 62 %) and low to moderate Pr/Ph ratios, which indicated the source rocks were affected by both paleo-productivity and preservation environment. A productivity-controlling model in Es 3 m was established along with a co-controlling model of productivity and preservation in Ed 3 , which was largely developed under the background of a warm-humid climate and strong depression-controlled fault activity. The development model of source rock in Es 1-2 can be concluded as a preservation model under a hot arid climate and weak fault activity. The development model of source rock in Es 1-2 can be concluded as a preservation model under a hot arid climate and weak fault activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The distribution of high production wells is related to the strike-slip fault zones. • Strike-slip faults provided a place for the development and alteration of reservoirs. • Four enrichment models were established through strike-slip faults and production characteristics. • Fault size, tension segment and structural highs affected the reservoirs. Uplifiting of the central Tarim Basin has attracted great interests since the discovery of a major condensed natural gas field in Ordovician carbonate successions at a depth of > 6000 m. The formation of the large-scale hydrocarbon reservoirs in reef shoals is typically thought to be influenced by paragenetic accumulation in the karstified reservoirs. However, because of the rapid decline of natural gas/petroleum production and the complex fluid distribution in limestone reservoirs, it is difficult to clarify the controlling factors of hydrocarbon enrichment. We integrate core, seismic, well logging and production data to illustrate the relationship hydrocarbon enrichment and fault system in this paper. First, productive wells are closely associated with major strike-slip fault zones. Second, most productive blocks are distributed in a banded or block-like manner within strike-slip fault sections. Third, strike-slip fault systems do not closely control reservoir quality; however, the enrichment of natural gas is linked to the development of strike-slip fault systems. Finally, all high-productivity wells are distributed around structural highs in major strike-slip fault zones. These lines of evidence suggest that the accumulation and enrichment of hydrocarbons were closely related to strike-slip fault zones rather than kastified reservoirs. Based on this, four models for the accumulation of hydrocarbons were proposed: fault uplift, graben periphery, fault intersection and fault–karst coupling. Large-scale strike-slip fault zones, transtensional segments and local structural highs were the main factors found to be controlling hydrocarbon enrichment and high productivity. Therefore, these three conditions improved the reservoir and provided paths and places for hydrocarbon migration and accumulation. These proposed hydrocarbon accumulation models contribute to a better understanding of these fault systems and further petroleum exploration. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Bainaimiao arc belt has a tectonic affinity different from the North China Craton. • The Precambrian basement of the Bainaimiao arc belt is laterally heterogeneous. • The Bainaimiao arc belt is an early Paleozoic composite arc system. As an important part of the southeastern boundary of the Central Asian Orogenic Belt (CAOB), the Bainaimiao arc belt, particularly its tectonic affinity and Precambrian basement composition, is an important element to provide new insights about the crustal growth of the CAOB. However, these remain poorly understood. This paper presents new geochronological, whole-rock geochemical and zircon Hf isotope data on early Paleozoic intrusive rocks from the Bainaimiao arc belt in the southeastern CAOB. The Ordovician gabbroic diorites in the Zhengxiangbaiqi area of the western Bainaimiao arc belt have low SiO 2 contents (51.73–54.82 wt%), high TiO 2 (0.99–1.07 wt%) and TFe 2 O 3 contents (9.68–9.89 wt%), depletions in Nb, Ta and Ti, and positive ε Hf (t) values (6.8–11.3). These rocks generated from partial melting of a mantle wedge that has been metasomatized by subducted-derived fluids. The Silurian monzogranites in the Zhengxiangbaiqi area have high contents of SiO 2 (72.61–75.12 wt%) and K 2 O (2.75–4.12 wt%), positive ε Hf (t) values (0.7–9.3) and abundant Precambrian inherited zircons. These monzogranites originated from partial melting of the thickened juvenile crustal components with significant ancient crustal contamination. The Silurian granites and granodiorites in the Faku area of the eastern Bainaimiao arc belt are characterized by high Na 2 O contents (4.00–4.52 wt%), high Sr/Y ratios, low MgO (1.15–1.74 wt%) and K 2 O contents (0.52–1.42 wt%), low K 2 O/Na 2 O ratios, and positive ε Hf (t) values ranging from 0.6 to 8.1. These rocks were derived from partial melting of a subducted slab interacted with mantle peridotite. New zircon U-Pb-Hf isotope data from these early Paleozoic intrusive rocks combined with previous results indicate that the Precambrian basement of the Bainaimiao arc belt is laterally heterogeneous, with Neoarchean-Paleoproterozoic basement beneath the western Bainaimiao arc belt and Paleo-Mesoproterozoic basement beneath the central Jilin area in the eastern Bainaimiao arc belt. The Bainaimiao arc belt has a tectonic affinity different from the North China Craton (NCC) and represents a composite arc system consisting of an ensialic island arc with a basement composition similar to that of the Precambrian microcontinents in the CAOB in the Bayan Obo-Damaoqi-Bainaimiao-Zhengxiangbaiqi and central Jilin areas and an oceanic island arc in the Ongniud-Faku and southern Jilin areas. The involvement of composite arc systems in the amalgamation of the accretionary orogenic belt could be an important mechanism for crustal growth in the CAOB. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Tarim Craton experienced both active and passive rifting during the Cryogenian. • The rift system shows a two-tiered architecture with narrow-deep Cryogenian grabens overlain by a broad Ediacaran depression. • Both active and passive rifting are thought to have been triggered by retreating subduction in the late Neoproterozoic. The Cryogenian-early Paleozoic succession in the Tarim Craton is generally regarded as a continuous rift sequence that followed the prolonged superplume-related breakup of Rodinia. However, the rift architecture and origin of the late Neoproterozoic basin are poorly known, but these are important for the understanding of the tectonic evolution of the basin and for the evaluation of the hydrocarbon potential. This paper aims to elucidate the rift architecture, distribution, origin and evolution of the late Neoproterozoic Tarim Basin by integrating outcrop investigations with well and seismic data. The late Neoproterozoic magma-rich active rifting primarily occurred in the northeastern part of the basin, whereas other areas experienced slightly younger magma-poor passive rifting. The Ediacaran succession overlaps in the northern basement uplift to show a pre-Ediacaran unconformity occurs in the northern Tarim Craton, while a sub-Cambrian unconformity traverses the entire Tarim Craton and presents a distinct truncation in the southern basement uplift. A tiered architecture exists in which narrow, deep Cryogenian grabens are overlain by a broad Ediacaran depression. Two NE-striking rift systems developed in the northeastern and southwestern Tarim. It can be inferred from the compiled data that the late Neoproterozoic rift basin evolution in the Tarim Craton can be divided into four stages: early Cryogenian rifting, late Cryogenian fault-graben, Ediacaran intracratonic depression, and end-Ediacaran regional uplifting. These results suggest that documented Neoproterozoic retreating subduction-related slab failure/detachment processes led to both active and passive rifting, which contributed to the diverse continental rift architecture and evolution of the late Neoproterozoic Tarim Basin. [ABSTRACT FROM AUTHOR]

• Using CMOM to trace mangrove development was first used in Thailand. • Three periods of flourishing and two periods of degradation over the past ∼3,550 cal yr BP. • The air temperature and rainfall controlled by the Indian summer Monsoon, were the primary factors controlling mangrove development. • The evolution of mangrove forests in tropical Asia has regional synchronism. High-resolution reconstruction of the development of mangrove forests in the late Holocene is the basis for scientifically predicting the fate of mangroves. In this paper, we analyze the contribution of mangrove-derived organic matter (CMOM) from sediment core G in Phang Nga Province, Thailand by using a ternary end-member mixing model based on stable organic carbon isotope (δ13C) and the molar ratio of total organic carbon to total nitrogen (C/N (molar)). The variations of the CMOM in Phang Nga Province over the past ∼3,550 cal yr BP indicate that mangrove forests underwent three periods of flourishing: ∼3,550–2,720 cal yr BP, ∼1,960–1,240 cal yr BP and ∼500–0 cal yr BP, and two periods of degradation: ∼2,720–1,960 cal yr BP and ∼1,240–500 cal yr BP. Of the potential factors that affect mangrove development, relative sea level (RSL) changes and regional hydrological conditions did not have notable effects on mangrove flourishing/degradation. However, paleoclimate variations, especially the air temperature and rainfall controlled by the Indian Summer Monsoon (ISM) were the primary factors. The mangrove development reconstructed by the CMOM in Phang Nga Province, Thailand was extremely synchronized with that in the Yingluo Bay and Qinzhou Bay of Southwest China and on the west coast of India Peninsula. This study provides evidence that mangrove development controlled by the Asian monsoon in tropical Asia has regional synchronism. [ABSTRACT FROM AUTHOR]

[Display omitted] The Zagros orogenic belt is a major mountain system located in southwestern Iran and extending into northeastern Iraq and southeastern Turkey. It was formed as a result of the Late Paleogene-Early Neogene Arabian-Eurasian continental collision, where its proto-basin was impacted by the tectonic evolution during the Proto-Tethys and Paleo-Tethys development. The entire evolution history can be summarized through an integrated model of three Wilson cycles. This paper aims to provide an understanding of the complexities of plate motions that led to the evolution of the Zagros Fold-and-Thrust Belt, by integrating the time and space evolution of supercontinents. A comprehensive review of the Arabian plate tectonics suggests three main tectonic stages, including a period of rifting from the Late Cambrian to Carboniferous, a period of ocean closure during the Late Triassic and Jurassic, and a final collision during the Cenozoic. These tectonic evolution stages encompassed multiple episodes of basin uplifting and subsidence, marked by wide-spread fault reactivation and fold deformation. Three styles of deformation were identified and characterized, including thin-skinned, thick-skinned, and basement deformation. The closure of the Neo-Tethys Ocean resulted in compressional tectonics that reactivated dormant faults, and emplaced gypsum-salt sedimentary caprock. The genetic analysis concurrently proposes a scientific framework for the characterization of structural deformation in similar convergent plate systems globally. [ABSTRACT FROM AUTHOR]

[Display omitted] • The genesis of Jurassic igneous rocks in the Yanbian area was related to the subduction of the Paleo-Pacific Plate. • The Paleo-Pacific Plate started subduction beneath the Eurasian continent at the Early Jurassic. • Slab tear occurred at the Late Jurassic and this was followed by oblique subduction of the Paleo-Pacific Plate. It is widely accepted that the subduction of the Paleo-Pacific Plate beneath the Eurasian continent began during the early Mesozoic; however, the details of the subduction process remain uncertain. This paper presents new zircon U–Pb–Hf and whole-rock geochemical data for Jurassic intrusive rocks from the Yanbian area of NE China to provide a better understanding of the subduction history of the Paleo-Pacific Plate. Zircon U–Pb dating results reveal that three stages of Jurassic magmatism are recorded in the Yanbian area, namely, Early Jurassic (188–179 Ma), Middle Jurassic (172–163 Ma), and Late Jurassic (158–156 Ma). Early Jurassic intrusive rocks from the Yanbian area are predominantly calc-alkaline gabbro, gabbro-diorite, quartz monzonite, granodiorite, and syenogranite. These geochemical features and rock associations are indicative of formation in an active continental margin setting related to the initial subduction of the Paleo-Pacific Plate beneath the Eurasian continent. The Early Jurassic granitoids were formed mainly by the partial melting of heterogeneous lower crust. The Middle Jurassic granitoids are geochemically similar to adakites and have ε Hf (t) values of + 2.0 to + 10.1. These rocks are inferred to have been derived from magmas generated by the partial melting of thickened juvenile lower-crustal material. Their formation was related to the subduction of the Paleo-Pacific Plate. Late Jurassic adakites in the Yanbian area formed in a compressional tectonic setting. Their negative ε Hf (t) values (−17.2 to − 8.6) and T DM2 ages (2025–1552 Ma) indicate that the primary magma was derived from the partial melting of ancient continental crust. Combining our data with the distribution of Late Jurassic igneous rocks in the NE Asian continental margin and the northward migration of Jurassic accretionary complexes along the margin, we conclude that the subduction of the Paleo-Pacific Plate beneath the Eurasian continent during the Late Jurassic–earliest Early Cretaceous had a low angle of obliquity. [ABSTRACT FROM AUTHOR]

• Geomorphology of the Paghman and Chaman faults were described based on fieldwork and satellite data. • A reverse fault was mapped west of and almost parallel to the left-lateral Paghman fault. • Based on field observation, the approximate length of surface rupture due to 1505 earthquake is ∼30 km. • The Paghman and Chaman faults could produce an earthquake of Mw 7.3–7.8 in the Kabul Basin. The city of Kabul, Afghanistan, lies within the Kabul Block, which is bounded by the Sarobi, Gardez and Paghman fault, the northern extension of the Chaman fault, accommodating oblique convergence between the Indian and Eurasian plates. In this paper, we describe the geologic structure and tectonic geomorphology of the northeast-striking Paghman fault and a ∼10-km-long portion of the Chaman fault using a combination of field observations and remote sensing data, and assess evidence for rupturing in the 1505 historical earthquake. The Paghman fault is predominantly a left-lateral strike-slip fault with a minor dip-slip component along the eastern margin of the Paghman Mountains. The Chaman and Paghman faults displaces Paleogene to Quaternary units with clear displacement of recent deposits. Continuous left-lateral movement of the both faults have caused stream deflection, capturing, abandonment, and finally, incision of alluvial deposits inside the Kabul Basin. We identify several stages in the alluvial fan development and displacement that were once a continuous unit displaced left-laterally as a single fan but are now incised by beheaded and offset stream channels. An approximately 30-km-long active fault trace is identified with geomorphic evidence of recent faulting and vertical offset ∼0.5–3 m, which we interpret is related to the historical 1505 earthquake in the area along the Chaman and Paghman faults. Our observations indicate significant along-strike variations in faults trace geometry. The seismic event comprises several fault segments separated by discontinuities such as stepovers. The two faults have accumulated enough elastic strain to cause a larger earthquake since the 1505 quake. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Miocene Zankan intrusion share geochemical affinities of high Ba-Sr rocks. • It was derived from garnet-phlogopite pyroxenite in enriched lithospheric mantle. • Isotopic shift in the Central Pamir mantle occurred from the Eocene to Miocene. • High Ba-Sr granitoids have a role in the generation of continental crust. High Ba–Sr granitoids differ from the I-, S- and A-type granitoids, and their petrogenesis and role in the evolution of the continental crust remain enigmatic. This paper reports a study of whole-rock geochemistry, and Sr–Nd isotopes, zircon U–Pb geochronology, and Lu–Hf isotopes of the Zankan high Ba–Sr intrusion in the Central Pamir. U–Pb dating of zircons suggests that the pluton was emplaced during the Miocene (10.2 ± 0.1 Ma). The Zankan rocks have high contents of K 2 O (3.83 to 12.3 wt%), Rb (212–483 ppm), Ba (701–6910 ppm), and Sr (503–3371 ppm). They have several geochemical characteristics that are consistent with A-type granitoids, such as high Na 2 O + K 2 O (8.10–14.2 wt%) and Zr + Nb + Ce + Y (336–1393 ppm) contents. All samples have enriched Sr–Nd–Hf isotope compositions, with 87Sr/86Sr i = 0.7097 to 0.7126, ε Nd (T) = −9.3 to −8.4, and ε Hf (T) = −12.2 to −4.0. Their isotopic compositions differ from those of mafic lower crust in the Central Pamir. Alternatively, the Zankan rocks may have been derived from an enriched lithospheric mantle. Combining our new isotopic results with data from the literature, we propose that a shift from isotopically juvenile to more isotopically evolved compositions in mantle-derived magmas took place from the Eocene to Miocene. The isotopic shift reveals that South Pamir lower crust was underthrusted beneath the Central Pamir lithosphere during the Miocene. Although high Ba–Sr granitoids generally exhibit "crust-like" isotopic characteristics, our data indicate that they play a role in continental growth. [ABSTRACT FROM AUTHOR]

[Display omitted] • In-situ elemental analyses of Fe (oxyhydr)oxides from Zhijin distinguish two types of Fe (oxyhydr)oxides. • Fe-(oxyhydr)oxides showed mainly hydrogenic origin mixed with hydrothermal origin. • Fe (oxyhydr)oxides control the enrichment of REE in francolites via Fe-redox pumping. • REEs were adsorbed by Fe (oxyhydr)oxides in oxic seawater and released in suboxic/anoxic porewaters. Marine phosphorites have shown extraordinary REE potential. Enrichment mechanisms have been investigated as yet, however, the roles of Fe/Mn (oxyhydr)oxides in REE enrichment were poorly known. In this paper, we report new data for early Cambrian phosphorites in South China with a particular focus on REE enrichment and Fe-redox cycling. Phosphorites from the Cambrian Gezhongwu occur in the upper and lower units. The phosphorites contain a large number of of Fe (oxyhydr)oxides, especially those in the upper unit. SEM and laser Raman show that Fe (oxyhydr)oxides have a gray rim and a bright core, attributed to transformation from hematite to goethite during the weathering. In-situ elemental analyses show Fe (oxyhydr)oxides have PAAS-normalized REE patterns depleted in LREE and enriched in HREE with negative to positive Eu anomalies and positive Y anomalies. However, two patterns are clearly distinguished according to Ce anomalies and these are related to the origins of Fe-(oxyhydr)oxides: hydrothermal Fe (oxyhydr)oxides with negative Ce anomalies and hydrogenic ones with positive Ce anomalies. The role of Fe (oxyhydr)oxides played in REE enrichment was controlled by Fe-redox pumping. In this process, Fe (oxyhydr)oxides adsorbed REEs in oxic water columns; after precipitating to suboxic/anoxic conditions, the absorbed REEs were released into porewater. Francolites subsequently formed and captured REEs during early diagenesis. Even though additional evidence is required, our investigations were significant in conforming the origins of Fe/Mn (oxyhydr)oxides and their role in REE enrichment in marine phosphorites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Middle Permian adakite, arc granitoids and high fractionated granite in the northern Qaidam Block have been identified. • Various magma sources contributed to the occurrence of these granitoids in the northern Qaidam Block. • The northern Qaidam Block was an active continental arc during the Middle Permian. • A five-stage model of subduction slab roll-back and subduction zone retreat for late Late Paleozoic to Early Mesozoic tectonic evolution of the northern Qaidam Block. Origin and tectonic setting of late Late Paleozoic to Early Mesozoic igneous rocks in the northern Qaidam Block (NQ) have long been a matter of debate. In this paper, we report new zircon U-Pb ages and Hf isotopic compositions and bulk rock major and trace elemental compositions for granitoids of the Yanchangbeishan area in the NQ. The granodiorite, tonalite, granodiorite, and syenogranite yielded zircon U-Pb ages of 271.9 Ma, 262.0 Ma, 272.4 Ma and 261.3 Ma, respectively, corresponding to ε Hf (t) values are 13.04–14.32, 8.14–10.77, 8.66–11.88, and 8.22–10.43, respectively. These granitoids are compositionally I-type granites and exhibit varying degrees of enrichment in Rb, Th, U, and K, and depletion in Nb, Ta, and Ti. According to field relationships, petrology, geochronology, and geochemistry, the granitoid types can be divided into three groups: (1) ca. 272 Ma granodiorites, which are formed through partial melting of metagreywackes and amphibolites derived from depleted mantle; (2) ca. 262 Ma tonalite, which represents a typical high-silica adakite derived from partial melting of subducted oceanic crust during the evolution of depleted mantle; and (3) ca. 261 Ma syenogranite, which is formed by the partial melting and high-degree fractional crystallization of mixed crustal materials. Considering our findings and the regional geological background, we propose a five-stage tectonic evolution model of subduction slab roll-back and subduction zone retreat for the late Late Paleozoic to Early Mesozoic of NQ. [ABSTRACT FROM AUTHOR]

[Display omitted] • A deep CNN-LSTM model infers interface depth. • The model predicts depths based on altitude variation and gravity data. • The deep CNN-LSTM model is robust up to 20% correlated noise. • The deep learning with ordinary kriging is capable of filling missing depth. • The approach is useful for subsurface characterization of thrust and fold belts. Geological interface depth modeling from the gravity field data is crucial for the exploration of oil and gas, mapping of sediment-basement interfaces and many other geological modeling studies. Two-dimensional radially averaged power spectrum analyses yield ensemble mean depth from the gravity anomaly which lacks information away from the focus of the depth point modeled. This paper aims to introduce a deep learning technique combining a convolutional neural network and long short-term memory network (CNN-LSTM) with variogram modeling to model interface depths using geospatial coordinates, Bouguer gravity anomaly and altitude variations data over the thrust and fold belts of North-East India. Prior to actual data analysis, the method is tested on a synthetic model. After the optimal network selection with the 'Relu' transfer function and 'Adam' optimization, the robustness of the CNN-LSTM model is examined and the test results show that the model is robust up to the data assorted with moderate level (∼20%) of correlated noise. The CNN-LSTM model detects important geological structures, subsurface faults, and thrust zones namely, Kohima Synclinorium, Naga and Disang thrust, and Eastern boundary thrust. Comparative results suggest that the CNN-LSTM is skillful based on the mean-squared error (MSE) between the observation and the prediction (MSE CNN-LSTM ∼ 0.014) relative to the other machine learning models (Adaptive-Neuro-Fuzzy-Inference System (MSE ANFIS ∼ 0.020), Random Forest with Extra Tree(MSE RF ∼ 0.075), Support Vector Regression (MSE SVR ∼ 0.025), Bayesian Neural Network(MSE BNN ∼ 0.116), Convolutional Neural Network(MSE CNN ∼ 0.022), Long Short-Term Memory Network(MSE LSTM ∼ 0.023), and Gaussian Process(MSE GP ∼ 0.095)) used in the study. We, therefore, conclude that the proposed approach is robust enough to model the various geological interface depths precisely with appropriate input data of geospatial coordinates, Bouguer gravity anomaly and altitude variation. The approach used here has potential and could be explored further in other complex geological provinces around the world. [ABSTRACT FROM AUTHOR]

[Display omitted] • Slip rates along the North Darhad Fault are 0.3–0.5 mm/yr over the last ∼ 8.4 ka. • Average recurrence interval of Mw7 earthquakes is ∼ 3.5 ka. • Mw7-7.5 earthquakes occur during temporal seismic clusters within the SW Baikal Rift. • Estimated age of the Darhad Basin is between 6.5 and 3.3 Ma. • Opening of the Darhad Basin fits well into the pull-apart model of deformation. The North Darhad Fault, a major N-S fault at the SW Baikal Rift, demonstrates weak present-day activity, but several morphotectonic features indicate the occurrence of strong surface-rupturing earthquakes in the past. The seismic potential of the North Darhad Fault has not been accurately assessed, leaving a gap in the assessment of the seismic hazard. In this paper we present remote and field morphotectonic and paleoseismological studies carried out along this fault system. A detailed topographic mapping of the fault scarp in alluvial surface and trenching across the fault revealed two paleoseismic events responsible for the scarp formation. Dating of organic remnants found in the cross-section allow estimating a Holocene age for the paleoearthquakes and bracket the vertical slip rates along the North Darhad Fault between 0.3 ± 0.06 mm/yr (min) and 0.6 ± 0.12 mm/yr (max) over the last ∼ 8.4 ka. The obtained morphotectonic and paleoseismological data suggest that the North Darhad Fault has produced two magnitude Mw7 earthquakes separated by mean recurrence period of ∼ 3.5 ka. We have demonstrated that within the SW Baikal Rift the ∼ M7-7.5 earthquakes likely occur during temporal clusters along the faults separated in space by up to 250 km. The slip rates along the North Darhad Fault allowed us to compute the age of the Darhad Basin at 6.5–3.3 Ma, suggesting a synchronous formation of fault-controlled horst-graben systems throughout the SW Baikal Rift. The opening of the Darhad Basin fits well into the pull-apart model of deformation between the two largest strike-slip fault systems - Bulnay in the south and Mondy-Tunka-Sayan in the north. [ABSTRACT FROM AUTHOR]

[Display omitted] • Neoproterozoic adakitic granodiorites, gabbro-diorites and high-K granites in South China. • The western Yangtze Block was an arc belt related to the oceanic slab subduction during the Neoproterozic. • The Neoproterozoic magmatism was triggered in an oceanic slab window in the western Yangtze Block. Neoproterozoic igneous rocks are widespread along the margins of the Yangtze Block and record key information on the tectonic evolution of the South China Craton. In this paper, we present a comprehensive study of zircon U-Pb ages, whole-rock geochemistry and Sr-Nd-Hf isotopes on the Neoproterozoic granodiorites, gabbro-diorites, and high-K granites in the western Yangtze Block. The granodiorites, gabbro-diorites and high-K granites were dated at 848 ± 5.3 Ma, 824 ± 5.1 Ma and 819 ± 1.5 Ma, respectively. The granodiorites have high Sr (567 ∼ 607 ppm) contents and Sr/Y (84.4 ∼ 88.0) ratios and low alkalis (Na 2 O + K 2 O = 4.3 ∼ 4.9 wt%) and Y (6.6 ∼ 7.1 ppm) and Yb (0.7 ∼ 0.9 ppm) contents, similar to typical adakitic rocks. They show low MgO (0.9 ∼ 1.3 wt%), Cr (15.2 ∼ 26.7 ppm) and Ni (3.6 ∼ 4.4 ppm) contents and positive ε Nd(t) (+1.7 to + 4.2) and ε Hf(t) (+3.0 to + 8.2) values. The parental magmas for granodiorites were generated by partial melting of thickened juvenile mafic lower crust. The gabbro-diorites are characterized by the enrichment in LREEs, significantly negative Nb, Ta and Ti anomalies, and positive ε Nd(t) (+2.2 to + 4.2) and ε Hf(t) (+5.8 to + 10.4) values. They are inferred to be derived from partial melting of lithospheric mantle modified by subduction-related fluids. The high-K granites display high Zr + Nb + Ce + Y (208 ∼ 366 ppm) and alkali (Na 2 O + K 2 O = 7.6 ∼ 8.4 wt%) contents, high 10000*Ga/Al (2.31 ∼ 2.64) ratios and zircon saturation temperatures, similar to A-type granites. We suggest that these granites were formed by the partial melting of felsic crustal materials under low pressure and high temperature conditions. The association of granodiorites, gabbro-diorites and high-K granites indicates Neoproterozoic oceanic slab subduction in the western Yangtze Block. We suggest that a subducting oceanic slab window can account for Neoproterozoic magmatism in the western Yangtze Block. [ABSTRACT FROM AUTHOR]