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The Baleigong granites, located in the western part of the southwestern Tianshan Orogen (Kokshanyan region, China), records late Paleozoic magmatism during the late stages of convergence between the Tarim Block and the Central Tianshan Arc Terrane. We performed a detailed geochronological and geochemical study of the Baleigong granites to better constrain the nature of collisional processes in the Southwest Tianshan Orogen. The LA‐ICP‐MS U‐Pb zircon isotopic analyses indicate that magmatism commenced in the early Permian (∼282 Ma). The granite samples, which are characterized by high contents of SiO2 (67.68–69.77 wt%) and Al2O3 (13.93–14.76 wt%), are alkali‐rich and Mg‐poor, corresponding to the high‐K calc‐alkaline series. The aluminum saturation index (A/CNK) ranges from 0.93 to 1.02, indicating a metaluminous to slightly peraluminous composition. Trace element geochemistry shows depletions in Nb, Ta, and Ti, a moderately negative Eu anomaly (δEu=0.40–0.56), enrichment in LREE, and depletion in HREE ((La/Yb)N=7.46–11.78). These geochemical signatures are characteristic of an I‐type granite generated from partial melting of a magmatic arc. The I‐type nature of the Baleigong granites is also supported by the main mafic minerals being Fe‐rich calcic hornblende and biotite. We suggest that the high‐K, calc‐alkaline I‐type granitic magmatism was generated by partial melting of the continental crust, possibly triggered by underplating by basaltic magma. These conditions were likely achieved in a collisional tectonic setting, thus supporting the suggestion that closure of the South Tianshan Ocean was completed prior to the Permian and was followed (in the late Paleozoic) by collision between the Tarim Block and the Central Tianshan Arc Terrane. [ABSTRACT FROM AUTHOR]

In order to unravel the Mesozoic sedimentation in response to multistage deformation of the western Ordos fold-thrust belt, combined zircon U-Pb and fission track analyses of single zircon grain are conducted for seven sandstone samples in the Helanshan area. Zircon FT ages are calculated using absolute uranium concentration determined by LA-ICP-MS during the procedure of zircon U-Pb dating. The newly-obtained zircon FT data show age features that are comparable with the previous zircon FT ages obtained by conventional FT methods (by which uranium contents are determined through an external detector to map induced fission tracks). The newly-obtained zircon FT ages have four subordinate FT age peaks (i.e., 225 Ma, 165 Ma, 125 Ma and 80 Ma) which are well matched with the regional geodynamic events occurred in the Late Triassic, Late Jurassic, Late Cretaceous and Early Cenozoic, respectively; and the zircon U-Pb ages have two main peaks at the Paleoproterozoic and the Late Paleozoic. The zircon U-Pb ages, integrating with the FT ages and available paleocurrents, suggest that the Paleoproterozoic basement rocks and Late Paleozoic plutonic rocks of the Alxa Block are the source rocks for the Triassic sandstones, and the Jurassic sandstones are associated with a multi-cycling sedimentation. The Jurassic sandstones contain recycled zircons that firstly deposited in the Triassic strata and subsequently exhumed during the Late Triassic-Early Jurassic. [ABSTRACT FROM AUTHOR]

Volcanic rocks preserved in the Houay kham area, Loei Fold Belt are important components of the giant Paleo-Tethyan igneous belt. These magmatic rocks, previously mapped as Triassic-Jurassic in age, are composed of dacitic tuff, brecciated rhyolite tuff and a small number of dioritic dikes. In this study, LA-ICP-MS zircon U-Pb dating results show that brecciated rhyolite tuff, dacitic tuff, and dioritic dyke samples have ages of 419.8 ± 1.6 Ma, 449.6 ± 2.6 Ma and 417 ± 4.9 Ma. These are the first documented Late Ordovician to Late Silurian volcanic rocks in the Loei Volcanic Belt or in Southeast Asia. Geochemical analyses of these rocks show that all are calc-alkali to high K, formed in a subduction-related, back-arc basin and are intermediate-acid igneous rocks. Dacitic and brecciated rhyolite tuff samples originated from partial melting of mafic crust with medium to strong crustal contamination and weak to medium fractional crystallization. Dioritic dyke samples originated from simultaneous partial melting of gabbroic and metasedimentary rocks with weak to no crustal contamination or fractional crystallization. In the early Ordovician the eastern branch of the Rheic ocean opened and the Indochina terrane drifted away from NE Gondwana and subsequently an Ordovician–Silurian Palaeo-Tethyan Ocean opened. [ABSTRACT FROM AUTHOR]

Evidence for the Jurassic–Cretaceous Yanshan Movement (Orogeny) was first identified in the Jingxi Basin, a part of the Yanshan fold-and-thrust belt (YFTB) along the northern margin of the North China Craton. The disconformity or angular unconformity within the Jurassic volcano-sedimentary successions in the basin was interpreted to have resulted from a period of incipient shortening during the Yanshan Movement, commonly known as event A. However, the absolute ages of both event A and associated Jurassic units remain controversial. Here, we present the results of zircon U–Pb geochronology for volcanic and clastic rocks from the Jurassic units in the Jingxi Basin. The results provide better constraints on the depositional ages of formations in the basin: (1) Early-to-early Middle Jurassic (175–167 Ma) for the Nandaling Formation; (2) middle Middle Jurassic for the Yaopo Formation; (3) late Middle Jurassic for the Longmen Formation; (4) early Late Jurassic for the Jiulongshan Formation; and (5) late Late Jurassic (157–149 Ma) for the Tiaojishan Formation. Stratigraphic and geochronological correlations indicate that the Jiulongshan Formation and the Tiaojishan Formation are of different depositional ages in different regions. The Longmen Formation in the Jingxi Basin is equivalent to the Haifanggou Formation in the eastern YFTB. Two sedimentary cycles separated by a sedimentary hiatus, shown as disconformity and local angular unconformity, have been identified in the Jurassic sequences of the YFTB. Depositional ages of the rocks above and below the disconformity, which lies between the Yaopo and Longmen formations in the Jingxi Basin, constrain the timing of event A to 167 ± 2 Ma (late Middle Jurassic). This event is the first phase of shortening deformation in eastern China induced by the paleo-Pacific plate subduction. We propose that the shortening period was relatively transient, in contrast to previous suggestions of long-duration shortening. [ABSTRACT FROM AUTHOR]

Epithermal gold deposits are typical precious metal deposits related to volcanic and subvolcanic magmatism. Due to the lack of direct geological and petrographic evidences, the origin of the ore-forming fluid is deduced from the spatial diagenesis-mineralization relationship, chronological data, physicochemical characteristics of mineral fluid inclusions, mineral or rock elements and isotopic geochemical characteristics. By objectively examining this scientific problem via a geological field survey and petrographic analysis of the Gaosongshan epithermal gold deposit, we recently discovered and verified the following points: (1) Pyrite-bearing spherical quartz aggregates (PSQA) occur in the rhyolitic porphyry; (2) the mineralization is structurally dominated by WNW- and ENE-trending systems and occurs mostly in hydrothermal breccias and pyrite-quartz veins, and the ore types are mainly hematite-crusted quartz, hydrothermal breccia, massive pyrite-quartz, etc.; (3) the alteration types consist of prevalent silicification, sericitization, propylitization and carbonation, with local adularization and illitization. The ore minerals are mainly pyrite, primary hematite, native gold, and electrum, with lesser amounts of chalcopyrite, magnetite, sphalerite, and galena, indicating a characteristic epithermal low-sulfidation deposit. The ore-forming fluid may have been primarily derived from magmatic fluid exsolved from a crystallizing rhyolitic porphyry magma. Further zircon U-Pb geochronology, fluid inclusion, physicochemical and isotopic geochemical analyses revealed that (1) rhyolitic porphyry magmatism occurred at 104.6 ± 1.0 Ma, whereas the crystallization of the PSQA occurred at 100.8 ± 2.1 Ma; (2) the hydrothermal fluid of the pre-ore stage was an exsolved CO 2 -bearing H 2 O-NaCl magmatic fluid that produced inclusions mainly composed of pure vapor (PV), vapor-rich (WV) and liquid-rich (WL) inclusions with a small number of melt- (M) and solid-bearing (S) inclusions; mineralization-stage quartz contains WL and rare PV, WV and pure liquid (PL) inclusions characterized by the H 2 O-NaCl system with low formation temperatures and low salinities; (3) the characteristics of hydrogen, oxygen, sulfur, and lead isotopes and those of rare earth elements (REEs) provide insight into the affinity between PSQA and orebodies resulting from juvenile crust or enriched mantle. Combined with previous research on the mineralogenetic epoch (99.32 ± 0.01 Ma), we further confirm that the mineralization of the deposit occurred in the late Early Cretaceous, which coincides with the extension of the continental margin induced by subduction of the Pacific Plate beneath the Eurasian Plate. The formation of the ore deposit was proceeded by a series of magmatic and hydrothermal events, including melting of enriched juvenile crust, upwelling, the eruption and emplacement of the rhyolitic magma, the exsolution and accumulation of magmatic hydrothermal fluid, decompression, the cooling and immiscibility/boiling of the fluid, and mixing of the magmatic fluid with meteoric water, in association with water-rock interaction. Image 1 • The Gaosongshan gold deposit is a typical LS epithermal deposit, formed in the late Early-Cretaceous. • Initial ore-bearing fluid exsolved from emplacing of rhyolitic magma. • Immiscibility or boiling is dominant in the mineralization, followed by mixing of meteoric water. [ABSTRACT FROM AUTHOR]

The Jiuyishan complex massif, located in the northern section of the Nanling region, is a combination of five plutons, namely, the Xuehuading, Jinjiling, Pangxiemu, Shaziling and Xishan plutons. Whole‐rock geochemistry, mineral electron microprobe analysis, zircon U‐Pb dating and Hf isotope analysis were carried out for the Jinjiling and Pangxiemu plutons. The zircon U‐Pb dating yields weighted mean ages of 152.9±0.9 Ma for the Jinjiling pluton and 151.7±1.5 Ma for the Pangxiemu pluton, with a narrow gap between them. The Jinjiling and Pangxiemu plutons both have geochemical characteristics of high SiO2, Al2O3, Na2O, K2O and low TiO2, MgO, CaO, P2O5 contents, with intense depletionS in Sr, Ba, Ti, Eu and enrichments in Ga, FeOT and HFSE, and these characteristics reflect an A‐type affinity. From the Jinjiling to the Pangxiemu plutons, the mineral composition of mica changes from lepidomelane to zinnwaldite, with increases in F, Li2O and Rb2O contents. The mineral composition of zircon changes from low Zr/Hf to high Zr/Hf, with increasing HfO2, P2O5 and UO2+ThO2+Y2O3 contents. The mineral compositions of feldspar indicate that the Pangxiemu pluton contains more alkali feldspar than the Jinjiling pluton. The whole‐rock geochemistry and mineral compositions reveal a higher degree of differentiation for the Pangxiemu pluton. The nearly uniform εHf(t) indicates the same source region for the two plutons: both were derived from partial melting of the lower crust, with small contributions of mantle materials. In addition, higher F, lower Nb/Ta and Zr/Hf ratios in the Pangxiemu Pluton suggest a closer relationship with the rare metal mineralization than for the Jinjiling pluton. [ABSTRACT FROM AUTHOR]

We investigate the late Miocene‐Pleistocene offshore sedimentary record of the Yakutat microplate to evaluate the spatial and temporal variations in rock exhumation and sediment routing patterns at the heavily glaciated and actively converging plate boundary in southeast Alaska. We present 1,456 new fission track ages and 1,372 new U‐Pb ages from double‐dated detrital zircons derived from fourteen samples collected from offshore. We integrate our results with published geochronology and thermochronology data onland and offshore in order to constrain grain provenance. We find that offshore strata deposited east of the fold and thrust belt are sourced from the rapidly exhuming areas along the entire Fairweather Fault, the northeastern part of the syntaxial region, as well as the slowly exhuming Insular superterrane. In contrast, the western strata are sourced from the emerging fold and thrust belt and the Chugach Metamorphic Complex located north of the plate boundary. In these samples we identified a change in sediment provenance, which we suggest marks the capture of the Bagley Ice Valley by the proto‐Bering Glacier at the transition from the early to late Pliocene. This implies that the modern Bagley‐Bering Glacier System is much older than previously known. Strata deposited at ~8.6 Ma suggest that extreme rapid exhumation was already ongoing in the late Miocene, which supports previous findings in deep‐sea deposits. Overall, the data help discern several stages in the evolution of sediment routing patterns in response to dynamic tectonic and surficial processes along this active convergent margin. Plain Language Summary: Strong collisional tectonic processes and voracious glacial erosion shape the coastal region of southeast Alaska. This interplay between tectonics and climate‐driven surface processes resulted in the highest coastal mountain range—the St. Elias Mountains. In this study we investigate the sediment deposited in the adjacent Gulf of Alaska to reconstruct the changes in sediment source regions and erosion rates since the late Miocene through Pleistocene. We apply the U‐Pb and the fission track dating methods on hundreds of detrital grains to derive the time of crystallization and the time of cooling below 250°C on individual zircons. We find that the growing coastal mountains influenced the evolving glacial catchments. We identified a shift in sediment provenance between the early and late Pliocene time that we explain by the capture of the Bagley Ice field by the proto‐Bering Glacier. A change to more local sediment sources and limited lateral mixing occurred after the mid‐Pleistocene climate shift to longer glacial cycles and more intense glaciation. Key Points: We present new detrital zircon fission‐track and U‐Pb ages from late Miocene to Pleistocene strata of the Yakutat shelfShift in sediment source area at ~3.6±1 Ma suggests capture of the Bagley Ice Valley by the proto‐Bering GlacierStrata east of the fold and thrust belt was sourced by rapidly exhuming rocks along the Fairweather Fault [ABSTRACT FROM AUTHOR]

The geochemical compositions and zircon U-Pb ages of the Muhuguan and Mangling plutons of the North Qinling Terrane (NQT), China, provide insights into the basement rocks involved in magma genesis and the Mesozoic tectonic evolution of the NQT. Monzogranites from the two plutons are characterized by high SiO 2 contents (69.3–77.0 wt%), low Mg numbers (0.21–0.38), enriched light rare-earth elements, Th, U, and Pb, depleted high-field-strength elements, and negative Eu anomalies. The source of the Mangling monzogranite is interpreted to have been deeper than that of the Muhuguan monzogranite, on the basis of its higher Sr/Y, (Dy/Yb) N , and (La/Yb) N ratios and lower SiO 2 content. Sr-Nd isotopic compositions indicate similar but heterogeneous magma sources for the two granites: 87Sr/86Sr i = 0.7070–0.7103 and ε Nd (t) = −7.0 to −15.0 for the Muhuguan granite, and 87Sr/86Sr i = 0.7054–0.7083 and ε Nd (t) = −7.9 to −16.0 for the Mangling granite. The zircon U-Pb age results fall into two groups: (1) syn -magmatic zircons (153 to 140 Ma); and (2) inherited zircons that define five age clusters, namely Neoarchean-Paleoproterozoic (2633–2103 Ma), Paleoproterozoic to Mesoproterozoic (1988–1377 Ma), Neoproterozoic (975–605 Ma), Paleozoic (535–382 Ma), and Late Paleozoic – Early Mesozoic (329–187 Ma). These data are consistent with a derivation of the granites by mixing between melted underplated juvenile crust within the NQT and melts from basement rocks similar to those of the Xiong'er Group within the southern margin of the North China Craton (S-NCC). The involvement of S-NCC material is also supported by the unradiogenic whole-rock Pb isotopic composition of the Muhuguan and Mangling granites, which is similar to that of the S-NCC basement rocks. These results suggest that the widespread Late Jurassic to Early Cretaceous granitoid intrusions within the NQT were generated in an extensional geological setting associated with mantle upwelling. Melts were derived from underthrust S-NCC basement material and juvenile Neoproterozoic basaltic rocks. • Inherited zircons of Mesozoic granites indicate heterogeneous magma sources. • Basement rocks of North China were involved in the granitic magmas. • Low-silica diorite originated from enriched mantle source. [ABSTRACT FROM AUTHOR]

The Caosiyao giant porphyry Mo deposit (1.76 Mt), which is the third largest such deposit in China, is located on the northern margin of the North China Craton and associated with the Caosiyao intrusive complex that was emplaced in Archaean metamorphic rocks. The intrusive complex consists of monzogranite and coarse‐, medium‐, and fine‐grained granite porphyries that yield U―Pb ages of 148.5 ± 1.2, 146.4 ± 1.0, 144.6 ± 1.0, and 142.8 ± 3.2 Ma, respectively. Four molybdenite Re―Os model ages range from 143.1 ± 2.4 to 145.3 ± 2.1 Ma, which are consistent with the U―Pb ages for the igneous complex. The geochronological data indicate that the multistage magmatic‐hydrothermal processes were important in the formation of the Caosiyao giant deposit. The rocks of the Caosiyao granitic complex have high contents of silica (SiO2 = 71.7–75.6 wt.%) and total alkalis (mostly K2O + Na2O > 8 wt.%), low contents of CaO and MgO, and exhibit peraluminous high‐K calc‐alkaline to shoshonitic affinities. They are enriched in large‐ion lithophile elements (e.g., K, Rb, U, and Th) and light REEs and depleted in Eu, Ba, Sr, Nb, P, and Ti. The geochemical characteristics indicate advanced fractional crystallization and that the rocks are strongly fractionated I‐type granites. The negative Hf isotopic compositions of the granitic rocks, combined with old two‐stage Hf model ages, indicate the magmas were derived from partial melting of the ancient lower crust of the North China Craton. All the intrusive rocks in the complex have relatively high Ce4+/Ce3+ ratios and oxygen fugacity, which would have facilitated Mo extraction into the melts owing to the much higher solubility of S as sulphate (SO42−) than sulphide (S2−). The magma crystallization temperatures decreased from 882°C to 770°C as the magma evolved. The multistage magmatic‐hydrothermal processes, and the prolonged fractional crystallization, combined with high magma oxygen fugacity are the key factors to form the Caosiyao giant Mo deposit. The tectonic setting of deposit formation was one of extension related to rollback of the subducting Palaeo‐Pacific Plate during the Late Jurassic to Early Cretaceous. [ABSTRACT FROM AUTHOR]

The Lunpola Basin plays a key role in determining the elevation history of the central Tibetan Plateau, which is closely related to uplift dynamics and paleoclimatic evolution. However, accurate age constraints on the basin stratigraphy reflecting tectonic, paleo-elevation and climate information have long been vigorously debated, mostly due to a lack of absolute age controls. Here, we found two altered tuff layers in the middle-upper Dingqinghu Formation (Fm.) in the basin stratigraphic sequence. Detailed lithological, mineralogical and geochemical analyses of the tuffs indicate that they came from trachyandesite and identify analcime as the typical alteration mineral, suggesting primary deposition. LA-ICP-MS zircon U-Pb dating of the tuffs yields concordant ages of 20.6 ± 0.1 Ma and 20.7 ± 0.1 Ma, indicating that the end of the Dingqinghu Fm., i.e., the Lunpola stratigraphic sequence, and the uplift of the plateau to its current high elevations occurred much later than previously estimated. The contemporaneous thick black oil shales in the Lunpola deep lake and biocoenosis together suggest that the climate was humid and warm during this period. • The trachyandesite tuffs of primary deposition altered into analcime. • Zircon U-Pb dating determines the ages of the tuff layers are 20.6 ± 0.1 Ma and 20.7 ± 0.1 Ma. • The suggested paleoclimate was humid and warm in central Tibet at least in the early-middle Miocene. [ABSTRACT FROM AUTHOR]

The North Lhasa terrane in Tibet is generally interpreted to be paleotectonically unrelated to the East African Orogen (EAO) and is instead thought to have derived from northeastern India or northwestern Australia. In this study, we present petrogenetic and geochronological results pertaining to the analysis of gabbros (ca. 652 Ma), diorites (ca. 658 and 646 Ma), and tonalites (ca. 652 Ma) from the North Lhasa terrane. The gabbros are calc-alkaline and exhibit arc-like geochemical features. Low positive zircon ε Hf (t) values (+1.0 to +3.8), high zircon δ18O (6.25‰ to 7.94‰), and low negative whole-rock ε Nd (t) values (−3.5 to −1.4) indicate that the gabbros were derived from the lithospheric mantle, with geochemical modification by a subduction component. The diorite suite is characterized by a wide range of whole-rock chemistries (e.g., SiO 2 = 51.33–61.98 wt%) and Hf–O–Sr isotopic compositions (ε Hf (t) = −10.8 to −0.1; δ18O = 5.17‰ to 7.11‰; I Sr = 0.706 to 0.710), and negative whole-rock ε Nd (t) values (−7.0 to −4.7). These diorites are geochemically similar to OIB and are interpreted to be products of the partial melting of a relatively deep mantle source (>85 km) prior to extensive modification by continental crustal material. The tonalites are adakitic and have moderate Mg# values (47–54), low compatible element abundances, positive zircon ε Hf (t) values (+3.4 to +6.2), high I Sr values (0.714 to 0.715), and small negative whole-rock ε Nd (t) values (−1.6 to −0.4). These tonalites most likely formed by the melting of thickened Mesoproterozoic continental crust. The generation of these ca. 650 Ma magmatic rocks was related to slab break-off in a collision zone. By integrating the findings of previous studies with the data of the present study, we suggest that the North Lhasa terrane was most likely located in the northern segment of the EAO in paleotectonic reconstructions of the Gondwana supercontinent. Unlabelled Image • Late Cryogenian magmatic rocks (ca. 658–646 Ma) occur in the North Lhasa terrane, Tibet. • They are related to slab break-off in a collision zone. • The North Lhasa terrane originated from the northern East African Orogen. [ABSTRACT FROM AUTHOR]

The Tashisayi nephrite deposit is located in South Altyn Tagh, in Qiemo County, Xinjiang Province, northwest China. It is a recent discovery in the vast, well-known Kunlun-Altyn nephrite belt distributed along the south of the Tarim Basin, producing more than half of the nephrite from the whole belt in 2017. Field investigations revealed that it is a dolomitic marble-related (D-type) nephrite deposit, but little is known about its age of formation and relationships between the granites and marble. Here we report field investigations, petrography of the nephrite, as well as petrography, geochemistry, geochronology of the zoisite-quartz altered intrusive rock and adjacent granites. An A-type granite is identified with a SHRIMP U–Pb zircon age of 926 ± 7 Ma, suggesting it was emplaced in an extensional tectonic environment at that time. The altered intrusive rock has a cluster of U–Pb zircon age of 433 ± 10 Ma, with similar trace element features to the A-type granite, suggesting it was formed in an extensional regime at this later time. Nephrite formed because of the metasomatism of dolomite marble by hydrothermal fluids. It is inferred that Ca2+ was released from the dolomitic marble by metasomatism forming Ca-rich fluids, which caused alteration of both the intrusive rocks (6.00–8.22 wt.% CaO) and granite (1.76–3.68 wt.% CaO) near the nephrite ore bodies. It is also inferred that Fe2+ from the granite migrated towards the dolomite marble. The fluids gave rise to the formation of Ca-minerals, such as zoisite, in the nephrite and altered intrusive rock, and epidote in the granite. Based on the contact relationships, similarity in hydrothermal processes, and consumption of Ca2+, the Tashisayi nephrite is considered to have formed at the same time as the alteration of the intrusive rocks, i.e. ∼433 Ma. The geochronological similarity (∼926 Ma, 433 Ma) of South Altyn and North Qaidam may suggest that tectonically they belong to one single complex in the past, which was offset by the Altyn Tagh fault (ATF). The similar formation ages of the nephrites from Altyn Tagh (433 Ma) and the previously studied areas of West Kunlun (378–441 Ma) and East Kunlun (416 Ma) indicate that these nephrites formed during the closure of Proto-Tethys and in the accompanying post-collisional, extensional environment. Image 1 • A-type granite identified with age of ∼926 Ma in the south Altyn Tagh. • Forming age for the Tashisayi nephrite deposit is ∼433 Ma. • Nephrite from the huge belt related to the Proto-Tethys closure with post-collisional extension. • Ca2+ from marble induce extensive metasomatism forming nephrite, zoisite/epidote nearby. [ABSTRACT FROM AUTHOR]

The Bayin River, the largest river in the northeastern Qaidam basin, plays an important role in the source‐to‐sink system and landscape evolution at the basin‐mountain boundary between the Qilian Mountains and the Qaidam basin in the northern Tibetan Plateau. In this study, we conduct field observation, topographic analysis, zircon U–Pb dating, and apatite (U–Th)/He dating to constrain the landscape and tectonic evolution of the Bayin River watershed. Bedrock zircon U–Pb dating indicates the age group of 420–450 Ma for far‐source sediments and the age group of >1,700 Ma for near‐source sediments in the Bayin River watershed. Detrital zircon U–Pb dating results from the Mesozoic and Cenozoic strata in the Bayin River watershed reveal that the most important source transition occurred during the Cretaceous. The Zongwulong Mountains gradually uplifted throughout the Cenozoic, along with decreasing far source and increasing near source based on detrital zircon U–Pb dating. Rapid uplift occurred across the Qilian Mountains during the late Cenozoic, leading to high normalized steepness indices, young apatite (U–Th)/He ages, and deep incised valleys at the basin‐mountain transition zone. The knickpoints caused by the latest headward erosion just reach an elevation of ~3,800 m on the river longitudinal profiles, indicating that the latest uplift magnitude is ~300–400 m relative to the basin surface of the Qaidam basin. Elevation distribution and apatite (U–Th)/He ages reveal that river incision leads to high relief in the Zongwulong Mountains and influences its tectonic evolution. Key Points: The tectonic setting of Bayin River watershed significantly changed from Jurassic to Cretaceous based on detrital zircon U‐Pb age spectrumSlight erosion in central Qilian Mountains and intense erosion at the basin‐mountain transition zone are revealed by apatite (U–Th)/HeRiver incision leads to high relief of the Zongwulong Mountains related to the central Qilian Mountains [ABSTRACT FROM AUTHOR]

The East Kunlun Orogenic Belt (EKOB) in northern Tibet provides an important record of the amalgamation of the Wanbaogou oceanic basalt plateau and the Qaidam Block. Here we report geochemical, geochronological, and Hf isotopic data for newly identified late Silurian–Early Devonian mafic–ultramafic igneous complexes from the EKOB at the northern margin of the Tibetan Plateau. These complexes are dominantly composed of gabbro and pyroxenite rocks. Three complexes yield zircon U–Pb ages of 398.8 ± 1.8, 420.2 ± 1.2, and 413.4 ± 0.78 Ma. The εHf(t) values of zircons range from +0.8 to +3.3 with TDM1 ages of 897 to 998 Ma. Modelling of the geochemical data indicates that these igneous complexes have a hybrid origin, involving depleted mantle fluids derived from a previous subduction event and crustal materials. The geochemical and geochronological data suggest that these complexes formed in a post-collisional setting linked to break-off of a subducted oceanic slab, which occurred after the Wanbaogou oceanic basalt plateau amalgamated with the Qaidam Block in the late Silurian–Early Devonian. [ABSTRACT FROM AUTHOR]

Provenance studies of the Central Canyon, Qiongdongnan Basin has provided significant insights into paleographic and sedimentology research of the South China Sea (SCS). A suite of geochemical approaches mainly including rare earth elemental (REE) analysis and detrital zircon U–Pb dating has been systematically applied to the "source-to-sink" system involving our upper Miocene–Pliocene Central Canyon sediments and surrounding potential source areas. Based on samples tracing the entire course of the Central Canyon, REE distribution patterns indicate that the western channel was generally characterized by positive Eu anomalies in larger proportion, in contrast to the dominance of negative values of its eastern side during late Miocene–Pliocene. Additionally, for the whole canyon and farther regions of Qiongdongnan Basin, the number of samples bearing negative Eu anomalies tended to increase within younger geological strata. On the other hand, U–Pb geochronology results suggest a wide Proterozoic to Mesozoic age range with peak complexity in Yanshanian, Indosinian, Caledonian and Jinningian periods. However in detail, age combination of most western samples displayed older-age signatures than the eastern. To make it more evidently, western boreholes of the Central Canyon are mainly characterized with confined Indosinian and Caledonian clusters which show great comparability with mafic-to-ultramafic source of Kontum Massif of Central Vietnam, while eastern samples largely bear with distinguishable Yanshanian and Indosinian peaks which more resemble with Hainan Island. Based on geochemistry and geochronology analyses, two significant suppliers and sedimentary infilling processes are generated: (1) the Indosinian collision orogenic belt in central-northern Vietnam, Indochina has ever played significant role in Central Canyon sedimentary evolution, (2) Hainan Island once as a typical provenance restricted within eastern Central Canyon, has been enlarging its influence into the whole channel, even into the farther western regions of Qiongdongnan Basin. [ABSTRACT FROM AUTHOR]

• The Wulong gold deposit was formed in the early Cretaceous. • The ore-forming fluids could be magmatic in origin. • The deposit was formed during lithospheric thinning of the eastern North China Craton. The Wulong deposit is the largest quartz vein-type gold deposit in the eastern Liaoning Province of China. The gold ore bodies are hosted by Mesozoic biotite-granites. The mineralization occurs as veins with lenticular shapes. Laser-ablation-ICP–MS zircon U–Pb dating was used to date the biotite-granite, granite porphyry, and fine-grained diorites at the Wulong deposit, yielding ages of 155.4 ± 0.9 Ma, 154.2 ± 1.2 Ma, and 123.1 ± 0.9 Ma, respectively. A sericite sample from the gold ore yields a 40Ar–39Ar plateau age of 122.8 ± 0.8 Ma (MSWD = 0.09). The calculated δ18O w values for the quartz range from 4.8% to 8.6% and the δD W values of fluid inclusion waters in quartz vary from −98% to −77%. The H–O isotope data indicates that ore-forming fluids could be of a magmatic origin. The δ34S values of metallic sulfides range from +1.1% to +2.4%, with an average of +1.8%, suggesting that the sulfur is derived from a magmatic source. The 3He/4He ratios of fluid inclusions in pyrite range from 0.36 to 0.65 Ra with an average of 0.50 Ra. The mantle helium involved in the ore-forming fluid ranges from 3.9% to 7.2%, indicating a crustal fluid source. The Wulong gold deposit was formed at ca. 120 Ma and it has a genetic association with contemporaneous fine-grained diorite. The Wulong deposit was formed during lithospheric thinning of the eastern North China Craton during the early Cretaceous. [ABSTRACT FROM AUTHOR]

The mafic to felsic intrusive rocks of Nay (IRN) are located in the northeast of the central Iranian block. In this study, we present new major and trace element geochemistry, U-Pb zircon ages, and Sr-Nd isotopic data to discuss the origin of the IRN postcollisional units. The oldest units in the Nay area belong to Paleocene-early Eocene volcanic and pyroclastic series including basalt-andesite, latite, dacite, and tuff. These series are crosscut by subvolcanic and granitoid rocks with lithological composition varying from quartz gabbro to K-feldspar granite. The youngest igneous activity is represented by quartz monzodiorite dikes. Hornblende-biotite quartz monzonite from Nay granitoids was dated at 40 Ma (zircon U-Pb). The IRN rocks are metaluminous to peraluminous with high-K calc-alkaline and shoshonitic affinities. They display enrichment in light REEs [(La/Yb)N = 3.79-8.71] and LILEs (such as Ba, Th, Rb, U, and K), with depletion in HFSEs (such as Nb, Zr, Y, and Ti). All rocks have negative Eu anomalies [(Eu/Eu*)N = 0.17-0.88] and relatively flat heavy REE patterns [(Gd/Yb)N = 1.12-1.69]. Granitoids have initial 87Sr/86Sr values from 0.7053 to 0.7061 and eNd values from -1.65 to -0.02 calculated at 40 Ma. The geochemical composition of IRN rocks along with the low ISr and positive eNd values and mantle model ages of 0.6-0.8 Ga indicate that two end-members, enriched mantle and a continental crust, were involved in the magma generation. We argue that the Eocene IRN magmatism occurred as a postcollisional product by asthenospheric upwelling owing to the convective removal of the lithosphere during an extensional collapse of the central Iranian block. [ABSTRACT FROM AUTHOR]

The Truong Son and Kon Tum terranes in northeastern Indochina are thought to, respectively, form part of the Indian and Australian margins of Gondwana and separated one another by the Tam Ky–Phuoc Son Ocean during the early Paleozoic. In this paper, we present results of a comprehensive geochronological and geochemical study on a trondhjemite–tonalite suite identified in the Tam Ky–Phuoc Son Suture Zone. LA–ICP–MS zircon U–Pb dating yielded weighted mean 206Pb/238U ages of 518.5 ± 7.1 Ma and 502.1 ± 6.0 Ma for the trondhjemite and tonalite, respectively. These are the oldest magmatic zircons recorded in this area so far. Both rocks consist primarily of plagioclase (oligoclase), quartz, with minor, variable amounts of hornblende and biotite. They have high SiO 2 , Na 2 O and Y, but low Al 2 O 3 , K 2 O, Sr and Rb contents, and are characterized by depletion in LREEs with flat HREE patterns. These features are similar to those of typical oceanic plagiogranites. Our new evidences from field geology, geochemistry, and zircon Hf isotopic data, along with previously published data from the Tam Ky–Phuoc Son Suture Zone, suggest that the plagiogranites were originated from extensive fractionation of hydrous basaltic magmas. Furthermore, they were generated in an intra-oceanic arc system above a northward subduction zone within the Tam Ky–Phuoc Son Ocean. The final closure of this ocean took place before the late Silurian, marked by collision of the Truong Son Terrane with the Kon Tum Terrane along the Tam Ky–Phuoc Son Suture Zone to form the Indochina Block. After elimination of the southeastward offset along the Red River shear zone and the clockwise rotation of Indochina relative to South China since the Tertiary, the eastern part of the Tam Ky–Phuoc Son Suture aligns well with the Kuungan Suture on Hainan Island, together they have likely recorded the final assembly of Gondwana in this region. Unlabelled Image • The fractionated–origin plagiogranites within the Tam Ky–Phuoc Son Suture Zone were emplaced in the Cambrian (520–500 Ma) • These rocks were generated in an intra–oceanic arc above a north–dipping subduction zone within the Tam Ky–Phuoc Son Ocean • Truong Son and Kon Tum were separated by the Tam Ky–Phuoc Son Ocean that closed before late Silurian to form the Indochina • The Tam Ky–Phuoc Son Suture likely joins the Kuungan Suture on Hainan Island, recording final assembly of Gondwana. [ABSTRACT FROM AUTHOR]

The Qibaoshan ore area is located in Wulian town, Shandong Province, which is an important polymetallic metallogenic zone containing gold, copper, lead, and zinc. The polymetallic mineralization is mostly related to the Qibaoshan complex. The Qibaoshan complex is composed mainly of pyroxene diorite, andesitic porphyrite, pyroxene andesite porphyrite, amphibole andesite porphyrite, diorite porphyrite, and granodiorite porphyry, among which granodiorite–porphyry is the main wall rock of gold and copper ore body, whereas lead and zinc mineralization is closely related to diorite porphyrite. A combined study of laser ablation–inductively coupled plasma–mass spectrometry zircon U–Pb dating and geochemical analyses (major and trace elements) for 5 Mesozoic plutons from the Qibaoshan complex was carried out to determine their ages, petrogenesis, and tectonic setting. The U–Pb zircon ages measured by laser ablation–inductively coupled plasma–mass spectrometry indicate that the Qibaoshan complex was emplaced in 3 stages, represented by the ~175 Ma pyroxene diorite, ~129 Ma andesitic porphyrite/ porphyrite, ~125 Ma granodiorite‐porphyry, and ~112 Ma diorite porphyrite. Systematic diagenetic chronology and rock geochemistry show that formation of ~175 Ma pyroxene diorite in Qibaoshan ore‐concentrated area is possibly related to the transformation environment from compression to extension of the Sulu orogenic belt and/or of the subduction of the Pacific Plate, whereas the formation of the Early Cretaceous subvolcanic rock has a volcanic arc affinity related to subduction of the Pacific Plate. Based on the previous studies, this paper argues that the metallogenic age of Qibaoshan polymetallic ore‐concentrated area is 125–105 Ma, which is formed in the volcanic arc dynamics environment of the Pacific Plate subduction in the Late Yanshanian. In addition, a small amount of 610–799 Ma and 1.8 Ga was developed in the samples of the pyroxene diorite and andesitic porphyrite, suggesting their source may have great affinities with South China. [ABSTRACT FROM AUTHOR]

The widely exposed Tanjianshan volcanic rocks in the North Qaidam Orogen (NW China) encode abundant information about early Palaeozoic magma origin and tectonic evolution. This research utilizes petrological, geochemical, and geochronological methods to investigate the last volcanic cycle (Formation d) of the Tangjianshan Group, aiming to reveal the tectonic evolutionary processes of the North Qaidam Orogen. Formation d can be further divided into two major volcanic sequences, that is, Formation d‐1/d‐4 and Formation d‐3. Formation d‐1/d‐4 is a set of intermediate–basic volcaniclastic rocks intercalated with volcanic lava and contemporary hypabyssal diabase–gabbro intrusive rocks. The rocks are characterized by high average concentrations of Al2O3, K2O, Na2O, and P2O5, pronounced differentiation of light (LREE) and heavy rare earth elements (HREE) and enrichment of LREEs and light‐ion lithophile elements (LILE), showing continental arc affiliation and enriched mid‐ocean‐ridge basalt (E‐MORB) characteristics. They have positive zircon εHf (t) values (7.5 to 16.1) and variable whole‐rock εNd (t) values (−2.7 to 7.0), with crustal Hf model ages (TDMC) and two‐stage Nd model ages (T2DM) ranging from 428 to 970 Ma and from 618 to 1,410 Ma, respectively. The magma may have originated from an enriched mantle source and experienced crustal contamination in a continental back‐arc basin. In contrast, Formation d‐3 is composed of volcaniclastic rocks intercalated with layered basaltic andesite and basalts. It has higher average concentrations of CaO, FeOT, and MgO, lower ΣREE and flatter REE patterns, lower average 87Sr/86Sr ratios (0.70557), higher average 143Nd/144Nd ratios (0.51285), and exclusively positive εNd (t) values (1.3 to 5.0), consistent with normal mid‐ocean‐ridge basalt (N‐MORB) influence. The magma may have been derived from a normal mantle source without significant modification, which probably formed in a rift‐related tectonic setting or even a mid‐ocean ridge that developed within a back‐arc basin. Magmatic zircons from Formation d‐1/d‐4 yield U–Pb ages mostly at 460–440 Ma, whereas zircons modified by continental exhumation‐related orogenic fluids are mainly dated at 430–420 Ma. Magmatic zircons from Formation d‐3 mainly have U–Pb ages of 440–430 Ma. Integrating the magma genesis and rock affiliation interpretations of this study with geological information for the study area and adjacent regions, a four‐stage tectonic evolutionary model is proposed for the early Palaeozoic North Qaidam Orogen: (a) oceanic subduction with arc magmatism (520–460 Ma), (b) continental collision with back‐arc magmatism (Formation d‐1/d‐4) (460–440 Ma), (c) mid‐ocean ridge extension with rift‐related magmatism (Formation d‐3) (440–430 Ma), and (d) continental exhumation with orogenic fluid modification (430–420 Ma). [ABSTRACT FROM AUTHOR]

The South Altyn orogen in West China contains ultra high pressure (UHP) terranes formed by ultra‐deep (>150–300 km) subduction of continental crust. Mafic granulites which together with ultramafic interlayers occur as blocks in massive felsic granulites in the Bashiwake UHP terrane, are mainly composed of garnet, clinopyroxene, plagioclase, amphibole, rutile/ilmenite, and quartz with or without kyanite and sapphirine. The kyanite/sapphirine‐bearing granulites are interpreted to have experienced decompression‐dominated evolution from eclogite facies conditions with peak pressures of 4–7 GPa to high pressure (HP)–ultra high temperature (UHT) granulite facies conditions and further to low pressure (LP)–UHT facies conditions based on petrographic observations, phase equilibria modelling, and thermobarometry. The HP–UHT granulite facies conditions are constrained to be 2.3–1.6 GPa/1,000–1,070°C based on the observed mineral assemblages of garnet+clinopyroxene+rutile+plagioclase+amphibole±quartz and measured mineral compositions including the core–rim increasing anorthite in plagioclase (XAn = 0.52–0.58), core–rim decreasing jadeite in clinopyroxene (XJd = 0.20–0.15), and TiO2 in amphibole (TiM2/2 = 0.14–0.18). The LP–UHT granulite facies conditions are identified from the symplectites of sapphirine+plagioclase+spinel, formed by the metastable reaction between garnet and kyanite at <0.6–0.7 GPa/940–1,030°C based on the calculated stability of the symplectite assemblages and sapphirine–spinel thermometer results. The common granulites without kyanite/sapphirine are identified to record a similar decompression evolution, including eclogite, HP–UHT granulite, and LP–UHT granulite facies conditions, and a subsequent isobaric cooling stage. The decompression under HP–UHT granulite facies is estimated to be from 2.3 to 1.3 GPa at ~1,040°C on the basis of textural records, anorthite content in plagioclase (XAn = 0.25–0.32), and grossular content in garnet (XGrs = 0.22–0.19). The further decompression to LP–UHT facies is defined to be >0.2–0.3 GPa based on the calculated stability for hematite‐bearing ilmenite. The isobaric cooling evolution is inferred mainly from the amphibole (TiM2/2 = 0.14–0.08) growth due to the crystallization of residual melts, consistent with a temperature decrease from >1,000°C to ~800°C at ~0.4 GPa. Zircon U–Pb dating for the two types of mafic granulite yields similar protolith and metamorphic ages of c. 900 Ma and c. 500 Ma respectively. However, the metamorphic age is interpreted to represent the HP–UHT granulite stage for the kyanite/sapphirine‐bearing granulites, but the isobaric cooling stage for the common granulites on the basis of phase equilibria modelling results. The two types of mafic granulite should share the same metamorphic evolution, but show contrasting features in petrography, details of metamorphic reactions in each stage, thermobarometric results, and also the meaning of zircon ages as a result of their different bulk‐rock compositions. Moreover, the UHT metamorphism in UHP terranes is revealed to represent the lower pressure overprinting over early UHP assemblages during the rapid exhumation of ultra‐deep subducted continental slabs, in contrast to the cause of traditional UHT metamorphism by voluminous heat addition from the mantle. [ABSTRACT FROM AUTHOR]

The Late Triassic igneous rocks in the Yidun terrane can provide vital insights into the evolution of Plaeo‐Tethys in western China. We present new zircon U–Pb, whole‐rock geochemistry, and Sr–Nd–Pb–Hf isotopic data for the Litang biotite monzogranites, Yidun terrane. The biotite monzogranites have a zircon U‐Pb age of 206.1±1.0 Ma (MSWD=1.9, n=30), which indicates Late Triassic magmatism. The biotite monzogranites display I‐type affinity, high Na2O (3.38–3.60wt%) contents, medium SiO2(67.12–69.13wt%), and low P2O5 contents (0.10–0.12wt%). They are enriched in Rb, Th, and Ba and depleted in Nb and Ta, with negative Eu anomalies (Eu/Eu∗=0.74–0.81). They have evolved Sr‐Nd‐Pb‐Hf isotopic composition, i.e., (87Sr/86Sr)i=0.714225 to 0.714763, negative εNd(t) values of –2.0 to –2.6 with two‐stage Nd model ages ranging from 1.01 to 1.05 Ga, negative εHf(t) values of –3.4 to –4.1 with two‐stage Hf model ages of 1.85 to 1.88 Ga, suggesting a matured crustal sources. Their low Al2O3/TiO2 ratios and medium Cao/Na2O ratios, medium Mg# and SiO2 contents, low [molar Al2O3/(MgO+FeOT)] values, and high [molar Cao/(MgO+FeOT)] values indicate that the Litang biotite monzogranite was formed by partial melting of metabasaltic rocks. Based on the previous studies, we propose that the Litang biotite monzogranite derived from the westward subduction and closure of the Ganzi–Litang ocean during the Late Triassic. The mantle wedge‐derived mafic melts provided sufficient heat for partial melting of ancient metabasalt protolith within the middle‐lower crust. [ABSTRACT FROM AUTHOR]

The West Junggar of the western Central Asian Orogenic Belt is one of the typical regions in the term of ocean subduction, contraction and continental growth in the Late Paleozoic. However, it is still controversial on the exact time of ocean‐continent transition so far. This study investigates rhyolites with columnar joint in the West Junggar for the first time. Based on zircon U‐Pb dating, we determined that the ages of the newly‐discovered rhyolites are between 303.6 and 294.5 Ma, belonging to Late Carboniferous–Early Permian, which is the oldest rhyolite with columnar joint preserved in the world at present. Geochemical results show that the characteristics of the major element compositions include a high content of SiO2 (75.78–79.20 wt%) and a moderate content of Al2O3 (12.21–13.19 wt%). The total alkali content (K2O + Na2O) is 6.14–8.05 wt%, among which K2O is 2.09–4.72 wt% and the rate of K2O/Na2O is 0.38–3.05. Over‐based minerals such as Ne, Lc, and Ac do not appear. The contents of TiO2 (0.09–0.24 wt%), CaO (0.15–0.99 wt%) and MgO (0.06–0.18 wt%) are low. A/CNK=0.91–1.68, A/NK=1.06–1.76, and as such, these are associated with the quasi‐aluminum‐weak peraluminous high potassium calc‐alkaline and some calc‐alkaline magma series. These rhyolites show a significant negative Eu anomaly with relative enrichment of LREE and LILE (Rb, Ba, Th, U, K) and depletion of Sr, HREE and HFSE (Nb, Ta, Ti, P). These rhyolites also have the characteristics of an A2‐type granite, similar to the Miaoergou batholith, which indicates they both were affected by post‐orogenic extension. Combining petrological, zircon U‐Pb dating and geochemical characteristics of the rhyolites, we conclude that the specific time of ocean‐continent transition of the West Junggar is the Late Carboniferous–Early Permian. [ABSTRACT FROM AUTHOR]

The early Precambrian basement of the North China Craton, China, records a complex history during the Neoarchean and Paleoproterozoic. Southern Jilin Province is one of the best regions to evaluate the early Precambrian crustal growth of the Eastern Block of the North China Craton. We herein present new zircon cathodoluminescence images, U-Pb dates, trace element and Lu-Hf isotope data for three late Neoarchean tonalitic-trondhjemitic-granodioritic (TTG) gneisses and one Paleoproterozoic mafic dyke from Tonghua region, southern Jilin Province. These results lent convincing support to the occurrence of multiple tectono-thermal events in southern Jilin Province during the Archean and Paleoproterozoic, and shed light on the formation and evolution of continental crust in the northeastern Eastern Block. Zircon LA-ICP-MS U-Pb isotopic analyses indicated three episodes of magmatism. Inherited (or captured) zircons with ages of ca. 2.6 Ga provided strong evidence for a pre-2.5 Ga magmatic event in this region. The second magmatic episode occurred at 2556-2522 Ma, as evidenced by extensive exposures of TTG gneisses. The third episode occurred at ca. 2200 Ma and is recorded by several mafic dykes that intruded the Archean TTG gneisses. Metamorphic zircons yielded consistent ages of 2493-2465 Ma, indicating a regional metamorphic event immediately after the late Neoarchean magmatism in southern Jilin Province. Zircon Hf isotope data of the TTG gneisses indicated that the main phase of crustal growth occurred in the late Neoarchean, with a minor input of Mesoarchean continental crustal materials. The combined geochronological, geochemical, and geological data suggested that the three episodes of crustal growth in the northeastern Eastern Block occurred at 2.8-2.7, 2.6-2.5, and 2.2 Ga. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Eastern Liaoyuan Accretionary Belt extends eastwards over the Dunhua-Mishan Fault. • Dunhua-Mishan Fault shows a 170 km sinistral displacement taking place in the late Mesozoic. • Tan-Lu Fault Zone has a total sinistral displacement of 205 km in NE China. • Dunhua-Mishan Fault records more strike-slip movement than the Yilan-Yitong Fault. Abstract The NE- to NNE-striking, continental-scale Tan–Lu Fault Zone (TLFZ) in NE China is subdivided into the ∼900 km long Yilan–Yitong Fault (YYF) in the west and the ∼1000 km long Dunhua–Mishan Fault (DMF) in the east. Both faults record sinistral displacement during the earliest Cretaceous, leading to an obvious offset of the boundary between the Liaoyuan Accretionary Belt (LAB) and the North China Craton (NCC). Previous studies have demonstrated that the LAB in the south of the eastern Central Asian Orogenic Belt (CAOB) extends eastwards into an area between the YYF and the DMF. The boundaries between the LAB and NCC indicate a 35 km sinistral displacement upon the YYF. However, it remains unclear whether the LAB extends to the east of the DMF, and the amount of sinistral displacement on the DMF is poorly constrained. Here we present lithological observations and U–Pb and Hf isotopic data from zircon to constrain the age and position of the LAB to the east of the DMF. The data indicate an eastward extension of the LAB across the DMF, suggesting the continuous presence of the LAB east of the TLFZ in NE China. The U–Pb ages, ε Hf (t) values, and two-stage model ages of zircons from the study area constrain the boundary between the LAB and NCC to an extension of the NE-dipping Chifeng–Kaiyuan Fault to the east of the DMF. The geological boundaries on both sides of the DMF indicate a 170 km sinistral displacement along the fault. Thus, the TLFZ has a total sinistral displacement of 205 km in NE China. The eastern branch of the TLFZ records significantly more movement due to its proximity to the Pacific Ocean, where subduction of oceanic crust might have caused sinistral faulting along the TLFZ. [ABSTRACT FROM AUTHOR]

The gold mineralization in the Longtoushan hydrothermal gold deposit is concentrated within the contact zone of the granitic complex. Whole rock geochemistry and in-situ U-Pb and Hf isotopic data were used to constrain the genesis and age of the granites and related Cu-Au mineralization in the Longtoushan Deposit. The granites mainly consist of the granite porphyry, rhyolite porphyry, porphyritic granite and quartz porphyry. LA-ICP-MS U-Pb dating of zircons from the granite porphyry, rhyolite porphyry and quartz porphyry indicates that they intruded from ca. 94 to 97 Ma. These intrusions exhibit similar trace element characteristics, i.e., right-dipping REE patterns, depletion of Ba, Sr, P and Ti, and enrichment of Th, U, Nd, Zr and Hf. The εHf (t) values of zircons from the granite porphyry, rhyolite porphyry and quartz porphyry range from −26.81 to −8.19, −8.12 to −5.33, and −8.99 to −5.83, respectively, suggesting that they were mainly derived from the partial melting of the Proterozoic crust. The Cu-Au mineralization is mainly related to the rhyolite porphyry and porphyritic granite, respectively. The Longtoushan granites were most likely formed in a post-collisional extensional environment, and the deposit is a part of the Late Yanshanian magmatism related mineralization in the Dayaoshan area and its adjacent areas. [ABSTRACT FROM AUTHOR]

• A Late Jurassic porphyry Cu-Mo deposit in the Erguna Block is reported. • Ore-bearing rocks were derived from the partial melting of the oceanic slab. • Petrogenesis of ore-related rocks related to a flat-slab subduction. The genesis of igneous rocks associated with the newly discovered Xiaokele porphyry Cu-Mo deposit, located in the eastern Erguna Block, NE China, can give insights into the regional geodynamic evolution during the Late Mesozoic. Several ore-bodies have been identified in a granodiorite porphyry stock, which intruded the rhyolite and was subsequently intruded by diorite porphyry and granite porphyry. The U–Pb ages of zircons from rhyolite, mineralized granodiorite porphyry, diorite porphyry and granite porphyry associated with the Xiaokele deposit are 152.5 ± 1.7, 150.0 ± 1.6, 147.9 ± 1.3, and 123.2 ± 1.7 Ma, respectively. The rhyolite and granite porphyry have high SiO 2 and low MgO, Cr, Co, and Ni contents. Their isotopic data show negative ε Nd (t) values of −4.76 to −0.87, initial 87Sr/86Sr ratios of 0.7066 to 0.7134 and positive zircon ε Hf (t) values of 0.33–5.56, indicating that they were derived from a basaltic lower continental crust. The mineralized granodiorite porphyry is characterized by high Sr/Y values and low Y (3.7–8.0) contents, showing adakite affinity. The low K 2 O/Na 2 O (0.51–0.7) ratios, high CaO contents, weakly negative ε Nd (t) (−1.17 to −0.27), and low zircon ε Hf (t) (1.49–5.4) values from the adakitic samples indicate that they were derived from the partial melting of an altered oceanic slab together with assimilation of mantle peridotite and crustal materials. The 148 Ma diorite porphyry has high Mg# (51–58), weakly negative and positive ε Nd (t) (−0.09 to 0.01) values, and lower (87Sr/86Sr) i (0.7055–0.7057) ratios, suggesting an enriched mantle wedge source. Considering the late Mesozoic regional tectonic evolution of the Erguna Block and adjacent area, we propose that the formation of the Xiaokele deposit is linked to the southward flat-slab subduction of the Mongol–Okhotsk oceanic plate during the Later Jurassic-Early Cretaceous. [ABSTRACT FROM AUTHOR]

• The Jinchang gold-rich porphyry deposit has experienced two mineralization phases. • It includes early Au–Cu (∼114 Ma) and late Au-only mineralization (103–101 Ma). • Jinchang deposit was formed by the subduction roll-back of the Paleo-Pacific Plate. Whether multiple mineralization styles in porphyry deposits are the result of one or multiple pulses of magmatism is unknown. In this paper, we present new age and geochemical data on the Jinchang porphyry gold-copper (Au-Cu) deposit, an important deposit in NE China and in the eastern Central Asian Orogenic Belt (CAOB). Field geological study suggests that both the mineralization and ore-causative magmatism at Jinchang are multiphase. LA-ICP-MS zircon U-Pb dating of the monzogranite ore host yielded 197 ± 1 Ma, which is considerably older than the ore-causative monzonite (115 ± 3 Ma) and granodiorite (107 ± 2 Ma). Molybdenite Re–Os dating on the breccia pipe-hosted Au-Cu ores yielded a well-defined isochron age of 114 ± 3 Ma, coeval to the monzonite emplacement. The Au-Cu mineralization was followed by another phase of crypto-explosive breccia pipe-hosted, disseminated/vein-type Au mineralization. This Au-only mineralization phase was auriferous pyrite Re–Os dated to be 103–101 Ma, coeval to the granodiorite emplacement. Geochemically, the monzonite and granodiorite are enriched in LILEs and LREEs, but depleted in HFSEs and HREEs. The ore-causative rocks are I-type and display continental arc geochemical affinities. We suggest that the monzonite and granodiorite were generated in an intracontinental extensional setting, probably caused by the Early Cretaceous subduction roll-back of the Paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]

• Batholithic biotite monzogranite (BMG) emplaced at ∼94 Ma. • Satellitic muscovite alkali-feldspar granite (MAG) emplaced at ~72 Ma. • The two-stage of granites indicates the existing of a long-lived magma chamber. • The MAG was from highly-fractionated magma in the magma chamber. • Hydrothermal zircons from the tin ore have a weighted mean age of 72.6±1.6 Ma. • The MAG is the source carrier for the Gejiu tin deposit. • The BMG, MAG and Gejiu tin district formed during the Youjiang orogenic movement. The Gejiu tin district of southern China is the largest tin–polymetallic ore district in the world. Even though the mining operation has lasted more than 2000 years in this area, the metallogenic mechanism of this gigantic tin mineralization is still controversial. Based on petrographic, geochemical, and zirconological information from this study, we present a particular model of the magma evolution and tin mineralization for the Gejiu tin district. The ore-forming processes involved both a batholithic biotite monzogranite (BMG) emplaced at ∼94 Ma and a satellitic muscovite alkali-feldspar granite (MAG) emplaced at ∼72 Ma. The BMG and the MAG were produced from a long-lived magma chamber by two stages of magmatic activity during intracontinental orogeny in the Youjiang block. The hiatus between the two magmatic stages indicates that the deep-seated magma chamber persisted during the dominant phase of the orogeny. Progressive fractional crystallization of the magma caused the extreme enrichment of incompatible elements, which include ore-forming components such as tin, aqueous fluids, and other volatiles, in the residual magma. When the regional tectonic environment evolved into the extensional regime at ∼72 Ma, the highly-fractionated residual magma ascended and once emplaced it formed the highly-evolved MAG with a mean zircon crystallization age of 71.8 ± 1.2 Ma. The MAG is temporally and spatially associated with cassiterite-bearing quartz vein (CQV) with a mean zircon crystallization age of 72.6 ± 1.6 Ma. This metallogenic model of the BMG–MAG–CQV association is generally applicable to other granite-related metallic deposits in South China, Southeast Asia and elsewhere (Australia, Bolivia, Brazil, USA, etc.). The recognition of this BMG–MAG–CQV association in regional geological survey may facilitate the future exploration for this type of deposit. [ABSTRACT FROM AUTHOR]

The Kenbale Cu mineralization occurrence related to the diorite is a newly discovered Cu mineralization event in the Bangong-Nujiang metallogenic belt, Tibet, China. The Cu mineralization is hosted in the contact between the monzogranite or biotite quartz diorite and the fine-grained diorite, which is the mineralization related intrusion. In order to constrain the Kenbale mineralization age, petrogenesis and tectonic setting, we conducted LA-ICP-MS zircon U-Pb dating and Hf isotopic analyses of the biotite quartz diorite and fine-grained diorite and also the whole-rock geochemical study of the biotite quartz diorite. Zircon UPb dating show that weighted mean 206Pb/238U ages of the biotite quartz diorite and fine-grained diorite are 123.5 ± 1.9 Ma (MSWD = 2.3, n = 16) and 118.9 ± 1.3 Ma (MSWD = 2.5, n = 18), respectively. The biotite quartz diorite is a high-K calc-alkaline I-type magma rock and was controlled mainly by partial melting process during the magma formation and evolution. This intrusion is characterized by positive εHf(t) values (2.6 to 5.8) and old Hf crustal model ages (813 to 1016 Ma), indicating that the magma was sourced from partial melting of the Mesoproterozoic to Neoproterozoic juvenile crust of the northern Lhasa Terrane. Compared with the biotite quartz diorite, the mineralization associated fine-grained diorite has much higher zircon εHf(t) values (8.2 to 11.4) and younger Hf crustal model ages (450 to 650 Ma). These characteristics are similar with those of the coeval magmatic rocks induced by slab break-off of the southward subducted Bangong-Nujiang Ocean. The geochronology and geochemical results show that the Kenbale Cu mineralization was controlled by the slab break-off of the southward subducted Bangong-Nujiang Ocean. [ABSTRACT FROM AUTHOR]

Abstract The Yizuomao area, located in the south segment of Lesser Xing'an Range–Zhangguangcai Range, is an important part of ore-concentrated area in the east of Ha'erbin. The Yizuomao Complex comprises medium- to coarse-grained, medium- to fine-grained and fine-grained biotite-bearing alkali feldspar granite, and the results show 206Pb/238U ages of 195.3 ± 1.8 Ma, 200.6 ± 3.2 Ma and 205.2 ± 4.1 Ma, respectively. The geological characteristics for these deposits indicate that a genetic link between the emplacement of granite porphyries and skarn-type mineralization. The ages of regional mineralization and crystallization of the granite porphyrie suggest that skarn mineralization in the Yizuomao area occurred during the late Early–early Middle Jurassic. The Yizuomao Complex and associated granite porphyries have similar characteristics, as both comprise high–K calc–alkaline rocks containing high concentrations of SiO 2 and K 2 O + Na 2 O, and low concentrations of Ti, Fe, Mn and Ca. The magmatic rocks are depleted in Ba, Nb, Sr, and Ti, and enriched in Rb, Th, U, K and Pb, and have high Rb/Sr ratios, characteristic of highly fractionated I-type granites. Moreover, all display positive ε Hf (t) values from +5.6 to +14.3, and young zircon Hf single-stage and two-stage model ages, suggesting a significant contribution of juvenile material. Based on the geochronology, geochemistry and Hf isotopic data, we suggest that the Yizuomao Complex and associated granite porphyries were derived from partial melting of juvenile crust. The Yizuomao Complex was emplaced in the transformation period from the post-collision extension of the NCC and the Jiamusi-Khanka Massif to the subduction of Paleo-Pacific Plate. The granite porphyries that are intimately associated with the mineralization were the result of magmatic activity along an active continental margin related to subduction of the Paleo-Pacific Plate. Graphical abstract Unlabelled Image Highlights • There is a genetic link between the emplacement of granite porphyry and skarn-type mineralization. • The skarn mineralization in the Yizuomao area occurred in the Early to Middle Jurassic. • The Yizuomao Complex and associated granite porphyry were derived from partial melting of juvenile crust. [ABSTRACT FROM AUTHOR]

Abstract The Ordovician–Silurian (O–S) transition was a period of dramatic climatic, environmental, and biological change. Numerous studies have documented the Late Ordovician glacial or mass extinction interval, but the Early Silurian has received significantly less attention. This study presents a U-Pb zircon age data and organic carbon isotope (δ13C org) records from the Upper Ordovician to Lower Silurian succession of South China to better constrain carbon isotope perturbations and to evaluate their possible causes and relationships to paleoenvironmental change during Early Silurian time. A volcanic ash bed located at the top of the organic-rich Lower Silurian Longmaxi Formation yields a 206Pb/238U zircon age of 440 ± 3 Ma (MSWD = 1.4), which is consistent with the Rhuddanian–Aeronian (R–A) boundary age. The newly acquired age is similar to that documented an ash bed in Scotland (439.57 ± 1.13 Ma) perhaps indicating synchronous volcanism. The δ13C org values show a negative excursion in the organic-rich lower Longmaxi Formation that is interrupted by a positive excursion in the organic-lean upper part of the unit. The positive excursion begins immediately above the dated ash bed thus assigning it to the R–A boundary. The documented δ13C org trend is comparable to those of other sections throughout the world, and is suggestive of a global perturbation of carbon cycle. The negative δ13C org excursion of the Rhuddanian stage was coeval with deposition of organic-rich shale under anoxic/euxinic conditions, whereas the subsequent positive δ13C org excursion coincided with a change to suboxic conditions that could have diminished organic matter preservation. We propose that the negative δ13C org excursion could be considered as the defining isotopic characteristic of the Rhuddanian oceanic anoxic event (Rhuddanian OAE). Results of the present study in tandem with published age data from the Guanyinqiao Bed immediately below the base of the Longmaxi Formation suggest that the negative δ13C org excursion and associated Rhuddanian OAE persisted for approximately 3 Myr. This relatively long-lived event reflects a sustained addition of isotopically light carbon into the atmosphere-ocean system, possibly related to the release of volcanic CO 2. The enhanced burial of organic carbon in association with the Rhuddanian OAE could have removed the substantial 12C from the carbon reservoir and lowered atmospheric p CO 2 thus resulting in a subsequent positive δ13C excursion and global cooling at the R-A boundary. [ABSTRACT FROM AUTHOR]

Multistage magmatic thermal events occurred in the Yardoi Dome and contain important information on the tectonomagmatic processes. The dome has played a crucial role in understanding the collisional evolution of the Tethyan Himalayan. We present new geochronological and geochemical data for muscovite-granite exposed in the Liemai area, Eastern Tethyan Himalayan Belt. Liemai muscovite-granite is strongly peraluminous, with A/CNK values characterized by evolved geochemical composition with high contents of SiO2-enriched large-ion lithophile elements, and is depleted of high-field-strength elements. These geochemical features indicate that granites possibly derived from partial melting of metasedimentary rocks and plagioclase fractional crystallization probably played a critical role in production of peraluminous granitic melts. Zircon U–Pb dating from muscovite-granite yielded ages of approximately 48.5 ± 1.1 Ma, representing its crystallization ages. This age is the oldest age of Tethyan Himalayan leucogranite from the Yardoi Dome and adjacent areas. However, the inherited zircon cores have ages of 135.7–3339.2 Ma. The εHf(t) values of all zircons vary from –6.4 to –2.3 and have varying Hf-isotope crustal model ages of 731–839 Ma. The geochemical and isotopic compositions indicate that magma of the Liemai granite can most likely be interpreted as products of the break-off related to thermal perturbation along the break-off window associated with the subduction of Neo-Tethyan slab. These magmas were derived mainly from the anatexis of ancient crustal materials under contraction and thickening conditions due to subduction of the Indian continent beneath southeastern Tibet. [ABSTRACT FROM AUTHOR]

The Hongshigang mafic-ultramafic intrusion, a newly discovered Permian Cu-Ni sulfide-bearing intrusion, is located in the eastern margin of East Tianshan Cu-Ni metallogenic belt, the northern Xinjiang, China. The intrusion is consist of peridotite phase, gabbro phase and diorite phase. The Cu-Ni sulfide is mainly hosted in gabbro phase and peridotite phase. Zircons separated from gabbro yield a concordia age of(280±1)Ma, similar to the ages of other magmatic Cu-Ni sulfide-bearing mafic-ultramafic intrusions in East Tianshan Cu-Ni metallogenic belt. The Fo and Ni contents of olivine crystals from the sulfide-barren samples vary from 82.2 to 87.3 and from 1 240×10-6 to 3 470×10-6 respectively, exhibiting a positive Fo-Ni correlation that is consistent with the fractional crystallization of olivine plus removal of small amounts of immiscible sulfide liquid. The Hongshigang intrusive rocks are characterized by light REE enrichment and negative Nb-Ta anomalies. The Nb/Yb-Th/Yb diagram indicates that the parental magmas for Hongshigang intrusion experiences 10%-20% crustal contamination, which should play a major role in triggering sulfide saturation in Hongshigang magma. In addition, the similarities in formation age, parental magma characteristic and sulfide saturation mechanism between Hongshishan intrusion and other known magmatic Cu-Ni sulfide ore deposits in East Tianshan Cu-Ni metallogenic belt, indicate that Hongshigang intrusion has potential to host a sulfide deposit [ABSTRACT FROM AUTHOR]

The Jiulianshan anticlinorium is located at the southern part of the Mount Maoshan–Jiulianshan in the Lower Yangtze region, where a number of new‐found thrust faults were identified. Movement of these thrust faults had resulted in Palaeozoic strata lying unconformably above Cretaceous strata. However, the Lower Yangtze region was mostly under an extensional tectonic regime during the Late Mesozoic, which is inconsistent with existence of the nappe in the Mount Maoshan–Jiulianshan. Therefore, what the structural characteristics are and when these thrust faults developed are important for understanding the evolution of the South China Block. Based on detailed field observations, these new‐found thrust faults outcropped in the Liqiao, Yangxian, and Miaopu areas. These faults, SE‐dipping deeply, developed a meters‐wide fault‐and‐fracture zone of width in meters. The footwall was composed of the Early Cretaceous pyroclastic rock or tuff, which indicates that these faults developed since the Early Cretaceous. Two undeformed dykes formed in the fault‐and‐fracture zone of Miaopu area and a footless intrusion in the hanging wall, which give emplacement ages of ca. 132 Ma by using zircon U–Pb LA‐ICP‐MS dating and thus implies that thrust fault motion occurred prior to or around this time. The volcanic tuff and pyroclastic rocks, located in the footwall of the Yangxian and Miaopu thrust fault, are dated at ca. 137 and 134 Ma, respectively, indicating that fault motion must have occurred after this time. The Qiaotouyang pluton emplaced in the core of one of the folds in the fold‐and‐thrust belt at ca. 141 Ma, which indicates that the fold‐and‐thrust belt of Tongling Uplift formed prior to 141 Ma. Integrating other evidences, such as magmatic quiescence, large‐scale and short‐duration volcanic eruptions, and beginning time of metamorphic core complex and rift basin, it is inferred that Early Yanshanian thrust faults were reactivated during the Late Mesozoic, resulting in thrusting within the Jiulianshan anticlinorium. [ABSTRACT FROM AUTHOR]

A large Late Palaeozoic A‐type granite belt lies along the Hegenshan‐Nenjiang‐Heihe belt in the Central Asian Orogenic Belt (CAOB). The Kuleqi, Naimanhe, and Gejiadian plutons at Yili are developed within this A‐type granite belt. The genesis and formation environment of these A‐type granites are controversial. The results of zircon SHRIMP UPb dating analyses indicate that the A‐type granites at Yili formed during the Late Carboniferous (302–307 Ma), and their geochemical data indicate that they principally represent a weakly peraluminous (A/CNK 1.01–1.21), high‐K calc‐alkaline series. These granites are enriched in HFSEs, Th, Rb, and K and depleted in LILEs, Ba, Nb, Sr, P, and Ti, which suggests that they record signatures of evolution of continental magma arc. The Nb/Ta ratios of these granites range from 6.84 to17.51, with an average value of 11.65, indicating that they represent crustal‐sourced magma. Their Zr/Hf ratios range from 37.05 to 88.70, with an average value of 59.72 (all values >39), suggesting that these rocks are dominated by mantle‐sourced components. The zircon Hf isotopic compositions of these rocks show εHf(t) values ranging from 6.8 to 12.5 (all positive), with an average value of 9.9, and depleted mantle two‐stage model ages ranging from 518 to 887 Ma, implying that these zircons may contain Early Palaeozoic–Neoproterozoic depleted mantle material. Based on these data, combined with their trace element characteristics, we conclude that the A‐type granitoids at Yili were mainly produced by the mixing of crust and mantle materials; together with their regional tectonic characteristics, these data indicate that these granitoids are related to the collision of the Xing'an and Songliao blocks, which was triggered by the subduction of the Palaeo‐Asian Ocean. [ABSTRACT FROM AUTHOR]

Abstract The vast expanse of Mesozoic igneous rocks in Hong Kong contain important geological records of late Mesozoic magmatic events and tectonic processes from the coastal region of Southeast China. Of these, the Ping Chau Formation in the northwestern New Territories is the youngest known stratum. We perform a detailed study of the volcanic rocks of the Ping Chau Formation utilizing zircon U–Pb dating, with major and trace elements geochemistry. LA-ICP-MS zircon U–Pb data reveal Early Cretaceous age from two volcanic rock samples, with zircon crystallization from magmas at 140.3 ± 0.8 Ma and 139.3 ± 0.9 Ma, respectively. These rocks have high contents of total alkalis (Na 2 O + K 2 O = 5.58–9.45 wt.%), high-field-strength elements and light rare earth elements, conspicuous negative Eu anomalies, and depletions in Nb, Ta, Ti, Sr, Ba and P. Using this data, in combination with previous studies on the late Mesozoic volcanic belt in Southeast China, we propose that the volcanic rocks of the Ping Chau Formation probably originated from deep melting of the crust in a back-arc extensional setting induced by the subduction of the paleo-Pacific Plate. This formation represents the final stages of Early Cretaceous volcanic activity in Hong Kong, as associated with large-scale lithospheric extension, thinning and magmatism. Our results provide new information that can be used in evaluating the significance of Early Cretaceous volcanism and tectonics in Southeast China. Graphical abstract Highlights • We report the occurrence of rhyolitic vitric tuff from the Ping Chau Formation, Hong Kong. • LA-ICP-MS zircon U-Pb dating suggests an Early Cretaceous age for these rocks. • They originate from the deep melting of crust in a back-arc extensional tectonic setting. • The back-arc extension was most likely induced by the paleo-Pacific Plate subduction. • Results suggest that volcanic activity in Hong Kong persisted between 140 Ma and 139 Ma. [ABSTRACT FROM AUTHOR]

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[Display omitted] • The granodiorite porphyry in the Xiayi Sn deposit formed at 138 Ma, determined by zircon U-Pb dating. • Cassiterite U-Pb dating indicates a Sn mineralization age of 136 Ma in the Xiayi Sn deposit, which is contemporaneous with the granodiorite porphyry. • Hf isotope analysis of zircon suggests the involvement of mantle materials during the formation of the granodiorite porphyry. • Trace element compositions of cassiterite reveal distinct roles of Ti, W, Fe, V, and Sc in the cathodoluminescence (CL) response. • Our research provides valuable insights into the extension of the southeastern coastal metallogenic Sn belt into western Fujian Province. The Xiayi Sn deposit, located in the Sanming city, southeast China, is the largest Sn deposit in Fujian province. The mineralization mainly consists of cassiterite-bearing veinlets and stockworks, and it is spatially associated with the granodiorite porphyry. Despite its economic significance, few studies have been carried out, and the mineralization age remains unknown. In this paper, we present the first geochronological data on the cassiterite and the associated granodiorite porphyry, Hf isotope of the zircon, and trace element compositions of cassiterite from the Xiayi Sn deposit. These data give precise age of the Sn mineralization and constrain its relationship with the granitic intrusion. Zircon U-Pb dating of the ore-related granodiorite porphyry yielded the age of 138.3 ± 1.8 Ma, which agreed well with the cassiterite U-Pb age of 136.5 ± 1.4 Ma, documenting the genetic link between the Sn mineralization and granitic magmatism. Zircon εHf(t) ranged from −4.5 to −1.8 with a weighted mean of −3.4 and the Hf model ages (TDM2) vary from 1.31 to 1.47 Ga with a mean value of 1.40 Ga. These data indicate that the granodiorite porphyry originates from the partial melting of the crustal materials of Mesoproterozoic basement and show the addition of mantle-derived materials, similar to typical Sn mineralized granite in the southeastern coastal tin belt and Nanling tungsten-tin belt. Besides, cassiterite from Xiayi deposit show clear CL-bright and CL-dark sector zonation in the cathodoluminescence images. LA-ICP-MS trace element analyses of cassiterites indicate a high Ti and Fe but low Nb and Ta contents in both CL-bright and CL-dark sector zones, while the W content is significantly high in the CL-dark zone and low in the CL-bright zone. Cassiterite trace element compositions together with the mineralization pattern and alteration assemblages indicate that Xiayi is a porphyry tin deposit. These results provide proof of the extension of the southeastern coastal Sn metallogenic belt and offer potential breakthroughs in tin deposit exploration in southwestern Fujian Province. [ABSTRACT FROM AUTHOR]

Middle–Late Triassic volcanism and contemporary granitoids in East Malaya provide significant insights into the magmatic evolution and geodynamic processes of the Paleotethyan Ocean in SE Asia. This paper presents new zircon ages and whole-rock geochemical data including Sr-Nd-Pb-Hf isotopic analyses for newly identified felsic volcanic rocks and granites in SE Peninsular Malaysia. Zircon geochronological data constrain their formation time at 238–235 Ma. All samples have relatively high SiO 2 contents with enrichment in light rare earth elements but have negative anomalies at Nb, Ta, Ti, and Eu on spidergrams. Calculated zircon saturation temperatures are between 840 °C and 957 °C. Samples have (87Sr/86Sr) i ratios between 0.70501 and 0.71014 and ε Nd (t) values ranging from −6.6 to −5.9, with (206Pb/204Pb) i = 18.45–18.77, (207Pb/204Pb) i = 15.68–15.71, and (208Pb/204Pb) i = 38.88–38.97. The zircon in-situ ε Hf (t) values and T DM2 ages range from −5.6 to +4.5 and 1.62 Ga to 0.98 Ga, respectively. The primary melting source which produced these felsic volcanic rocks and granites was Proterozoic crustal rocks with a juvenile middle-lower crustal component. Triassic volcanism in SE Peninsular Malaysia northerly correlates with synchronous volcanic rocks in the Lancangjiang and Chiang Khong-Lampang-Tak volcanic zones. Our data, along with regional observations, indicate that these volcanic rocks and granites formed in a localized extensional setting in response to the Paleotethyan slab breakoff. While the initial collision of Sibumasu with East Malaya may have occurred at ∼237 Ma. [Display omitted] • Felsic volcanic rocks and granites in SE Peninsular Malaysia formed at 238–235 Ma. • Triassic felsic magmatism formed in response to the Paleotethyan slab breakoff. • The initial collision between Sibumasu and East Malaya might occur at ∼237 Ma. • Felsic volcanic rocks in East Malaya can correlate with the LCJ and CLT zones. [ABSTRACT FROM AUTHOR]

[Display omitted] • A paleo-megalake was reconstructed by tectonics, geomorphology, and sedimentation. • The late Pleistocene megalake deposits were eroded rather than fault-induced sinking. • Tectonic and climatic effects jointly controlled the evolution of megalake. • The megalake was a short-lived episode in the fluvial sedimentary cycle. Exploration of paleo-lake evolution is crucial for the understanding of climatic and tectonic roles in earth surface. Previous studies mainly focused on the climatic effect on river-lake transitions and lake evolutions through lacustrine deposits, but with limited consideration of tectonic drivers, especially for the tectonic rift lakes in the Hetao area. Based on the analyses of lacustrine and fluvial piedmont terraces and a 400-m core from the northern Hetao Basin, along with the optically stimulated luminescence and detrital zircon U-Pb dating, we adopted an integrated "tectonics-climate-surface processes" approach to explore the climatic and tectonic effects on the lake evolution of the Hetao rift basin. Results show that lacustrine deposition on the piedmont terrace T1 (60–47 ka), underlying the T3 fluvial (80–60 ka), has an erosion contact with pluvial deposits at 55 ka, implying the paleo-lake formation at ∼ 80–60 ka and shrinkage at ∼ 55–47 ka. Lake formation was forced by basin depression under the tensile stress of tectonic movement, and was recharged by the Yellow River due to obstruction of the outlet at Tuoketuo caused by uplift. Lake shrinkage was due to the combined effect of basin lifting and warm-wet climate conditions that promoted outflow. A substantial decrease in the erosion base level and rapid water drainage induced by river cutting caused erosion of lacustrine deposits in the basin. The limited sedimentary space of the lake basin in early MIS 2 should be considered a factor in lake disappearance in addition to the dry climate. This study highlights that tectonic effects may be more important than climatic effects in the evolution of rift lakes near the young fold mountain belts. [ABSTRACT FROM AUTHOR]

[Display omitted] • An epithermal gold deposit with fluid boiling as the primary precipitation mechanism. • Formed around 97.5 Ma in the early Late Cretaceous. • Formed in an arc-extensive environment associated with the slab rollback of the subducted Palaeo-Pacific Plate. The origin and evolution of the newly discovered Yidonglinchang gold deposit in the Lesser Xing'an Range, Northeast China, remain poorly understood. This article focuses on the investigations of the geological characteristics, fluid inclusions, H-O-S-Pb stable isotopes and geochronology of the deposit. The Yidonglinchang gold deposit is mainly controlled by NEE-trending faults, and the ore bodies are present in volcanic rocks of the Early Cretaceous Ningyuancun Formation (K 1 n). Silicification, pyritisation, and argillization zones develop sequentially from near the ore center outwards. The ore minerals mainly include electrum and argentite. The gangue minerals are mainly quartz, calcite, and a small amount of sericite, plagioclase and adularia. The main gold-bearing minerals are quartz and calcite. The primary fluid inclusion types in quartz are pure-liquid-phase, gas-rich-phase, and liquid-rich-phase inclusions. Most of the inclusions are classified as a H 2 O-NaCl system which were formed under low-temperature, low-salinity conditions, indicating that Yidonglinchang is an epithermal gold deposit. The occurrence of boiling fluid inclusion assemblage indicates that the fluids underwent decompression boiling. Sm-Nd dating of calcite from the main ore-forming stage yields an age of 97.5 ± 2.3 Ma, which is interpreted as the timing of mineralisation. Zircon U-Pb dating of dioritic porphyrite yields ages of 98.8 ± 1.1 and 98.0 ± 1.3 Ma, which are consistent with the mineralisation age, suggesting a potential genetic link between the intrusive rocks and the ore formation. H-O-S-Pb isotopic compositions indicate that the ore-forming fluids were magmatic water during the early mineralisation stage, with the addition of meteoric water during the late stage. These isotopic compositions are also indicative of an origin of the ore-forming materials from the mixed crustal and mantle components. The mineralisation of the Yidonglinchang gold deposit was related to the slab rollback of the subducted Palaeo-Pacific Plate in the early Late Cretaceous. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Ahadawa deposit is a newly discovered porphyry Cu–Mo system in the North Qaidam. • The Ahadawa formed by more than 25 Ma prolonged magmatic-hydrothermal activity. • The Late Triassic fertile magmas initially had high water and high oxygen fugacity. • Plagioclase-dominated fractionation occurred with magma evolution. Ongoing exploration in the North Qaidam, Northern Qinghai-Tibet Plateau, NW China, has led to the identification of a porphyry Cu-Mo system centered on Ahadawa. In this study, we conducted a detailed geochronological and geochemical study on porphyritic monzogranite from the Ahadawa deposit, which hosts the Cu-Mo mineralization. The weighted mean zircon U-Pb ages for three mineralized porphyritic monzogranite samples from different sites range from 218.8 ± 1.2 Ma (MSWD = 1.5) to 224.7 ± 1.6 Ma (MSWD = 1.8), and finally to 233.1 ± 0.9 Ma (MSWD = 1.4, n = 23). These results, combined with antecrystic grains as old as ∼ 245.7 Ma, collectively indicate more than 25 Ma multi-stage magmatic emplacement activity in the Ahadawa deposit. Corresponding to complex magma episodes, six studied molybdenite samples yielded variable Re-Os model ages ranging from 436.7 ± 6.6 to 232.6 ± 1.2 Ma, with the three youngest dates constraining a weighted mean Re-Os age of 234.0 ± 6.8 Ma. The 234 Ma mineralization age is consistent with the observed Late Triassic magmatism, whereas the Re-Os model ages of 436.7 to 245.7 Ma, if they remain robust through future investigation, may highlight a long-lived hydrothermal activity in the Ahadawa deposit. Whole-rock and zircon compositions indicate that the Late Triassic porphyries occurring at the surface display distinct geochemical features, with the early porphyritic monzogranite of 233.1 Ma characterized by much higher whole-rock Sr/Y, and zircon Eu/Eu* and Ce/Ce* than the younger (218.8 Ma and 224.7 Ma, respectively) porphyritic monzogranite. This suggests that the Late Triassic magmas were initially characterized by high water content and high oxidation state and the differences between the old and two younger groups might be related to plagioclase-dominated fractionation. The finding of the Ahadawa porphyry system highlights the need for ongoing exploration (especially in poorly studied remote areas) and systematically geochronological and geochemical studies to constrain the temporal and spatial evolution of mineralized episodes within a complex, protracted magmatic history. [ABSTRACT FROM AUTHOR]

Mineralogical, geochemical and geochronological results of the Huayangchuan uranium (U)-polymetallic deposit. (a)-(d) Backscattered electron (BSE) images of titanite grains collected from Huayangchuan REE-U-Nb-Pb deposit; (e)-(h) backscattered electron (BSE) images of the betafite (main U-Nb-bearing mineral phase in Huayangchuan deposit) and its alteration; (i) and (j) LA-ICP-MS U-Th-Pb ages of the titanite from the Huayangchuan deposit; (k) primitive-mantle-normalized trace element spider diagram of Taihua Group gneiss (gray lines), pegmatite (orange lines) and carbonatite dykes (red lines); (l) chondrite-normalized rare earth element (REE) pattern of Triassic titanite (red lines) and Cretaceous titanite (green lines). [Display omitted] • C and O isotopic compositions and zircon U-Pb ages identified the Triassic carbonatite magmatism in the Huayangchuan deposit. • Titanite U-Pb isotopic dating revealed two sets of ages for mineralization: during the Late Triassic and the Early Cretaceous. • Late Triassic carbonatite magmatism (∼220 Ma) was responsible for the U-Nb-REE mineralization. • Early Cretaceous hydrothermal fluid (∼140 Ma) contributed to the Nb, Ti and U remobilization. The supergiant Huayangchuan uranium (U)-polymetallic deposit is situated in the west part of Lesser Qinling Orogen, Central China, which is renowned for its unique metallogenic type and complex mineralization processes. This newly-discovered deposit contains economic endowments of U, Nb, Pb, Se, Sr, Ba and REEs. The genesis of this deposit remains hugely controversial and the related magmatic and metallogenic framework have not been well established. In our study, we present newly obtained zircon U-Pb age data, whole-rock trace elements, detailed SEM observation, carbon and oxygen isotope determination and titanite U-Pb age result to provide geochemical and geochronological constraints on the magmatic and hydrothermal metallogenic processes in Huayangchuan ore district and give insight into the REE, Nb and U mineralization and remobilization mechanism. Carbonatite in Huayangchuan deposit is rich in Ba, Sr, Nb, U and REE and the δ18O SMOW and δ13C PDB (‰) values of carbonatite vary between + 7.30 ‰ to + 9.80 ‰ and − 6.00 ‰ to − 7.20 ‰, respectively, which is the unique characteristic of igneous carbonatite. The total REE contents of carbonatite range from 1319.5 to 2535.8 ppm, significantly higher than that of the granite pegmatite dykes and Taihua Group granitic gneiss. Two zircon grains from the Huayangchuan carbonatite yield the 206 Pb / 238 U age of 223 ± 5.6 Ma and 217 ± 8.6 Ma. Uranium and niobium are mainly hosted in the primary mineral of betafite, minorly in uraninite and fergusonite. REE are remained in various REE carbonates, phosphates and silicates, e.g. allanite, parite, monazite, apatite, yttrialite and xenotime. Betafite contains numerous mineral inclusions of calcite, allanite and apatite, which displays as vermicular relicts with metasomatic corrosion texture. The intimate relationship between betafite, calcite, apatite, allanite and REE carbonates implies that U and Nb mineralization occurred during carbonatite-related magmatic stage. Late Triassic carbonatite magmatism (∼220 Ma) was responsible for the world-class U-Nb-Mo-REE mineralization in the Qinling Orogen. Whereas, LA-ICP-MS U-Pb data of titanite collected from Huayangchuan carbonatite reveal two sets of ages in the Huayangchuan deposit: during the Late Triassic and the Early Cretaceous. LA-ICP-MS data of the Triassic titanite and Cretaceous titanite in Huayangchuan deposit yield the lower intercept age of 223.1 ± 9.4 Ma and 141.9 ± 4.7 Ma respectively in the Tera-Wasserburg (238U/206Pb - 207Pb/206Pb) diagram. Cretaceous hydrothermal titanites show enrichment in Y, HREEs and depletion in TiO 2 and LREEs relative to the Triassic magmatic titanites. Primary betafite and titanite were subjected to later hydrothermal alteration. The close genetic relation between altered titanite and Ti-Fe-Nb-Pb-U mineral inclusions demonstrates that Early Cretaceous hydrothermal fluids contributed to the Nb, U and Ti remobilization. Early Cretaceous regional granitic magmatic activity brought hydrothermal fluids to alter the early carbonatite magmatic pyrochlore and titanite. U, Nb, Ti, Y, Pb and HREEs were transferred and subsequently re-precipitated into uraninite, and hydrothermal titanite. [ABSTRACT FROM AUTHOR]

The Bagaladong Pb-Zn deposit is located in the eastern segment of the Gangdese back-arc uplift belt and lacks enough study with no available ages for ores and rocks. Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) zircon U-Pb dating and in situ trace elements were carried out for mineralization-related biotite granite in the Bagaladong Pb-Zn deposit and are reported in this paper. The crystallization temperatures of zircons in the biotite granite are obtained by using the zircon Ti thermometer. Trace element composition of zircons in the biotite granite indicates a magmatic origin. Fourteen zircons yield a weighted average 206Pb/238U ages of 129.1±2.3 Ma (MSWD=1.5), suggesting that the biotite granite was established in the middle of the Early Cretaceous, which is consistent with the age of magmatic intrusions obtained by previous studies. Zircon has ΣLREEs values of 13.21-530.28 μg/g with an average of 61.90 μg/g and ΣHREEs values of 849.16-3981.54 μg/g with an average of 1826.91 μg/g. Zircon has left-inclined REEs patterns with relative LREEs depletion and HREEs enrichment. These zircons have δCe and δEu values of 1.20-701.77 and 0.01-0.12, respectively, indicating obviously positive Ce anomalies and negative Eu anomalies. Zircons have Ti contents varying from 0.60 to 7.40 and crystallization temperatures of 593.9-795.3℃ with an average of 724.3℃, which partially reflect the diagenetic temperature. It can be concluded that the Bagaladong biotite granite was probably formed during the extrusion stage of collision after the closure of the Bangong Co-Nujiang ocean basin. The age of the biotite granite in the Bagaladong deposit represents the upper limit of the metallogenic epoch and provides important evidence for prospecting the Early Cretaceous Pb-Zn mineralization in the east section of the Gangdese back-arc fault uplift area.

The Tianshan Orogen (TO) is one of the largest typical accretionary orogenic belts in the world. Of which, the late Paleozoic was a critical era to understand the tectonic and geodynamic transition from accretion to collision. However, the late Paleozoic tectonic evolutionary history, especially for the time of the ocean‐continent transition, is still debated although the origin and tectonic settings for the Paleozoic volcanic, felsic igneous magmatism in TO and reginal geology have been done in the last decades. In contrast, the researches on the mafic dykes in TO was not systematically carried out till now. Reginal‐scale mafic dykes are commonly regarded as the products created in a extensional setting, and used to identify the major tectonic events such as rifting and continental break‐up and further trace the mantle natures and geodynamic mechanism (Halls, 1982; Bleeker and Ernst, 2006; Li et al., 2008; Ernst et al., 2010; Srivastava, 2011; Hou, 2012; Peng, 2015; Peng et al., 2019). There are widespread late Paleozoic mafic dykes beside the huge of intermediate‐acid igneous rocks in the TO, being an idea object to reveal the extensional events, tectonic evolution and the mantle nature and geodynamic processes. We present the ICP‐MS in situ zircon U–Pb dating, Lu‐Hf and whole‐rock Sr‐Nd isotopes as well as the geochemistry data for these mafic dykes to better constraint their petrogenesis and mantle nature. New zircon U‐Pb dating for 12 samples from the representative basic dykes and basalts yield three distinct stages of ∼332 Ma, 316–302 Ma and 288–282 Ma, respectively. In which, the first stage of mafic dykes is mainly occurred in both East Tianshan Orogen (ETO) and West Tianshan Orogen (WTO), and composed of dolerite with minor basalts. The second stage of mafic dyke also can be found in both ETO and WTO. However, in contrast to the first stage of mafic dykes, they have relatively variable rock types from the dolerite/or gabbros to gabbroic diorite. The third stage of mafic dykes are slightly intermediate in composition, and chiefly consist of andesitic‐basaltic dolerite with some diorites. They are widely developed not only in both ETO and WTO, but also in the Beishan area to the east of the ETO, indicating a large‐scale mafic magmatism in Tianshan and adjacent areas. Geochemically, first stage of mafic dykes is characterized by low SiO2 content of 47.23–47.09 wt% in ETO and 48.69–51.31 wt% in WTO with the variable Mg# values varying from 48.24 to 60.8 in ETO and from 54.26 to 59.14 in WTO. They evolved towards Fe‐depletion along the calc‐alkaline trend. Some of dykes display a slightly negative Sr anomalies and minor negative Eu anomalies (δEu=0.84–0.96), indicating a calc‐alkaline series with a the clinopyroxene‐ and plagioclase‐dominated fractionation. While, those sharing the positive Eu and Sr anomalies are most likely indicative of some degree of plagioclase accumulation. All mafic dykes have relative higher and variable LREE {(La/Yb)N=1.61–9.39} as well as LILEs (Rb, Ba and K) and depletion in HFSE with evident peak of Pb and valley of Nb. They show coherent zircon Hf and whole rock Sr‐Nd‐Pb isotopic composition, with a low (206Pb/204Pb)i (18.79) and variable (87Sr/86Sr)i (0.7033–0.7060) and positive variable ∊Nd(t) from 3.69 to 10.14 and ∊Hf(t) from 3.24 to 13.09. In addition, these mafic dykes have high Zr/Nb (13.6–48.6, average 30.9), and low La/Nb (2.1–5.1, average 3.2) ratios, showing a similarity to those of MORB mantle melts (Zr/Nb=30, La/Nb=1.07) (Sun and McDonough, 1989) rather than OIB asthenospheric mantle melts (Zr/Nb=5.3, La/Nd=0.77, Sun and McDonough, 1989). Their higher Zr/Y (2.5–6.8, average 4.0) and Nb/Y (0.1–0.5, average 0.2) ratios further suggest that they were derived from partial melting of a depleted lithospheric mantle (Bradshaw and Eugene, 1993; Condie, 2005). However, their Nb/La (0.20–0.49, average 0.35), Nb/U (3.3–17.8, average 8.6) and Ce/Pb (1.1–11.8, average 6.84) ratios are very low, much close to those of the continental crust (Nb/La=0.4, Nb/U=6.15, Ce/Pb=3.9, Rudnick and Gao, 2003), indicating crustal contamination (Xia and Li, 2014). All geochemistry and isotope composition favor that they were derived from a heterogeneous mantle source mixed by both depleted lithosphere mantle and EMI, and then experienced crustal contamination during the magma ascending. Second stage of mafic dykes have variable SiO2 content of 46.71–54.92 wt% in ETO and 48.53–52.59 wt% in WTO and variable Mg# values from 45.94 to 55.74 in ETO and from 27.04 to 53.64 in WTO and FeOT/MgO values higher than 1 (1.75–2.33 in ETO, 1.71–5.35 in WTO), showing a calc‐alkaline series in ETO and tholeiitic series in WTO associated with a certain extent magmatic evolution. However, many of the chemical and Sr‐Nd‐Hf isotopic features are in accord with those of first stage of mafic dykes. They are characterized by the right deviation REE pattern with slightly high LREE, moderate fraction between LREE and HREE {(La/Yb)N =2.55–7.52} and Eu (δEu =0.85–1.10) anomalies as well as the enrichment in LILEs (Rb, Ba and K) and poor HFSEs with obvious depletion of Nb and peak of Pb. Furthermore, they, just like first stage mafic dyke, have relatively depleted zircon Hf and whole rock Nd isotopic composition with a higher ∊Nd(t) (2.68–9.73) and ∊Hf(t) (2.55–15.46) but variable (87Sr/86Sr)i of 0.7036–0.7157 and high (206Pb/204Pb)i of 19.26‐19.78. They also display a higher Zr/Nb (10.3‐50.7, average 22.3), La/Nb (1.1‐3.7, average 2.51), Zr/Y (2.4–10.3, average 5.3) and Nb/Y (0.05–0.5, average 0.3) as well as low Nb/La (0.27–0.91, average 0.46), slightly high Nb/U (4.59–26.80, average 13.28) and Ce/Pb (2.21–16.94, average 7.71) ratios. All geochemistry and isotopic composition suggest they have a mantle source similar to those of first stage of mafic dykes, and originated from partial melting of a heterogeneous mixing source composed of the depleted lithosphere mantle and EMII. The third stage of mafic dykes, like the second stage of mafic dyke, have variable SiO2 ranging from 46.39 to 52.69 wt% in ETO and 49.62 to 54.68 wt% in Beishan area, and belong to a calc‐alkaline series. They have moderate Mg# values from 41.86 to 55.24 in ETO and from 41.7 to 55.28 in Beishan area, and exhibit negative Sr anomalies and medium negative or slight positive Eu anomalies (Eu/Eu=0.56–1.08), indicating plagioclase‐dominated fractionation during magma evolution. They are enriched in LILEs and LREE {(La/Yb)N = 3.16–6.38} and depleted in HFSEs with the valleys of Nb and Ti and a peak of Pb. They have narrow (87Sr/86Sr)i (0.7040 to 0.7050) and low (206Pb/204Pb)i (18.41). Their eNd(t) values are positive and variable, ranging from 5.36 to 10.36. While, their eHf(t) range from −7.13 to 18.33. Furthermore, like early mafic dykes, they are also characterized by the higher Zr/Nb (13.0‐29.8, average 20.57), La/Nb (1.0‐3.4, average 2.35), Zr/Y (3.2–6.8, average 4.8) and Nb/Y (0.1–0.4, average 0.3) as well as low Nb/La (0.29–1.00, average 0.50), Nb/U (3.21–17.53, average 7.92) and Ce/Pb (1.73–10.79, average 6.75) ratios. All suggest they were derived from a source inherited from early heterogeneous depleted lithosphere mantle involved in EMI and subjected crustal contamination during magma ascending. In summary, the late Paleozoic mafic dykes widely developed in the TO can be subdivided three distinct stages of mafic magmatism, and shear the consistent rock associations, petrogeochemistry and isotopic compositions. Three stages of mafic dykes are relatively enriched in LREE, LILEs and depleted in HFSEs with the valleys of Nb and Ti and a peak of Pb and slightly fractionation between LREE and HREE. They are coherently characterized by positive and variable ∊Nd(t) and ∊Hf(t) values, low (206Pb/204Pb)i and variable (87Sr/86Sr)i isotope ratios. Furthermore, they have higher Zr/Nb, La/Nb, Zr/Y and Nb/Y and low Nb/La, Nb/U and Ce/Pb ratios. All suggest that these late Paleozoic mafic dykes were mainly originated from a long‐lived unitary heterogeneous lithospheric mantle mixed by EMI and possible minor MEII and experienced varying degrees crustal contamination during the magma ascending. Consequently, based our new geochemical and Sr‐Nd‐Pb‐Hf isotopic data and combined with the previous studies on the reginal geology and widespread late Paleozoic post‐collisional magmatism (Xu et al., 2013; Xia et al., 2004, 2013), it can be proposed that the arc‐microcontinents collision in the TO started at least before the early late Carboniferous (Serpukhovian), and the mafic dykes with three distinct stages of ∼332 Ma, 316–302 Ma and 288–282 Ma were generated in a lithosphere extensional settings after arc‐microcontinents collision from late Carboniferous to early Permian. [ABSTRACT FROM AUTHOR]

The Zhuxi ultra-large type copper-tungsten deposit in the Northeast Jiangxi province located in Taqian -Fuchun metallogenic belt which belongs to Jiangnan ancient island-arc, the discovery of the deposit has verified Southern Tungsten North Expansion perspective and challenge the viewpoint that Tungsten located in the south but the copper located in the north of Jiangxi provience, but the previous lack of accurate chronology study related to Zhuxi copper-tungsten mineralization of granite not enough, resulting in the geodynamic background of understanding. In this study, on the basis of detailed field investigation, core logging and petrology studies on the granodioritic porphyries which had intruded into the Middle Proterozoic Shuangqiaoshan group and with copper mineralization alteration, using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating, we obtained the granodioritic porphyries zircon 206Pb/238U weighted mean age of 847.2±9.4Ma (MSWD=0.111), which can represent the granodiorite porphyry magma emplacement and crystallization age, belonging to the neoproterozoic. The results reveal that the granodioritic porphyries of Zhuxi copper-tungsten mine is a product of the early Neoproterozoic Southern China ancient oceanic crust subduction and Yangtze and Cathaysian continental blocks collisional magmatism, the magmatic activity provides the basis for the metallogenic Qinzhou-Hangzhou metallogenic belt, and the magma event is close related to the Taqian-Fuchun ore belt mineralization, it also provides new evidence for the study of Zhuxi ultra-large type copper-tungsten deposit.