Modern pollen morphology provides important information on plant taxonomy, systematics and evolution. Fossil pollen grains have been effectively used in palaeobotany and palaeoecological study. However, it's difficult to identify dispersed fossil pollen grains under traditional light microscope (LM) for those similar pollen types (e.g., species from Poaceae). In recent years, spectroscopic techniques have provided new approaches for detecting pollen chemical composition, thereby improving taxonomic resolution and palaecological implication. Among these techniques, fluorescence lifetime imaging microscopy (FLIM) has attracted increasing attention due to its high resolution, non-destructive, and sensitivity to pollen wall chemistry. In this study, we use FLIM to study Sonneratia pollen, including 6 species (Sonneratia ovata, S. apetala, S. & times; gulngai, S. alba, S. & times; hainanensis, and S. caseolaris). The results demonstrate that FLIM data can effectively classify Sonneratia pollen in four groups: 1) Sonneratia apetala, 2) S. & times; hainanensis, S. caseolaris and S. & times; gulngai, 3) S. ovata, and 4) S. alba. Moreover, the observed classification patterns allow a preliminary assessment of phylogenetic relationships between two hybrid taxa and their parental species. Notably, distinct fluorescence lifetime signatures were identified between the introduced species S. apetala and other native Sonneratia species in China, potentially reflecting differences in their biogeographic histories and ecological adaptations. FLIM provides valuable information on taxonomy, biogeography, and systematics according to our modern pollen examination for Sonneratia. Given FLIM data from fossil pollen can be comparable to extant species, this approach shows potential significance for improving species-level identification of fossil pollen of Sonneratia. Therefore, FLIM opens a new window to understand palaeoecology, evolution history and historical biogeography of tropical mangrove.

Debates persist over the tectonic evolution of the Bangong-Nujiang Meso-Tethys Ocean (BNTO), especially the hypothesis about its southward subduction. There is a lack of evidence for its southward subduction beneath the northern Lhasa terrane due to the presence of sedimentary cover and ambiguous geodynamic interpretations. To address this issue, this study investigated the Early Cretaceous granitoids (116-108 Ma) in the Xiongmei-Bange area located along the northern margin of the Lhasa terrane. The results indicate that the granitoids consist of two distinct suites: peraluminous and metaluminous granitoids. Among these, the peraluminous granitoids exhibit A/CNK ratios ranging from 1.03 to 1.47 and moderate enrichment in isotopic signatures, with epsilon Hf(t) and epsilon Nd(t) values varying from -5.1 to +2.4 and from -10.7 to -5.9, respectively. These granitoids were derived from the amphibolitic lower crust metasomatized by subducted sediments. In contrast, the metaluminous granitoids manifest A/CNK ratios ranging from 0.99 to 1.06, high enrichment in Nd-Hf isotopes, with epsilon Hf(t) and epsilon Nd(t) values ranging from -8.7 to -0.9 and from -11.2 to -8.0, respectively, and elevated Mg# values varying from 50 to 63. They originated from the partial melting of the ancient lower crust, with significant mantlederived contributions, a source composition indicated by their metaluminous character, enriched Nd-Hf isotopes, and elevated Mg#, which collectively reflect limited influence from subducted sediments compared to the peraluminous suite. The results suggest that the southward subduction of the BNTO may have commenced during the Middle Jurassic, with slab rollback at about 130 Ma and subsequent slab breakoff at around 115 Ma potentially triggering asthenospheric upwelling. This process could have induced lithospheric mantle melting and crustal anatexis, leading to the formation of the two granitoid suites. Slab rollback and breakoff are interpreted to have destabilized the overriding plate, causing the lithospheric subsidence in the northern Lhasa terrane during the Early Cretaceous. This subsidence likely induced a major marine transgression (Langshan Formation, 115-98 Ma). Consequently, the Jurassic - Early Cretaceous magmatic arc was covered by shallowmarine carbonates, effectively masking direct evidence of southward subduction. By integrating slab dynamics (i.e., possible rollback and subsequent breakoff) with the burial history, this study proposes a model that addressed the long-standing debate over the apparent absence of an arc-trench system.

Identifying Accurate identification of coal mine water-inrush sources is fundamental to water-hazard prevention, yet existing methods face three challenges: gradual chemical transitions among aquifers, scarce labeled samples (often under 50), and test-information leakage from improper preprocessing that systematically overestimates performance. Traditional hydrochemical methods rely on univariate thresholds and low-dimensional projections inadequate for multiclass discrimination.This study constructs a leakage-free deep learning framework integrating hydrochemical and isotopic evidence at the Lvtang Coal Mine (Guizhou, China). Twenty-eight samples spanning four classes (MW, MW-G, SW, GW+RW) used 29 features (13 core, 16 derived). Under leave-one-out cross-validation, winsorization, feature selection, imputation, and standardization were independently fitted within each training fold. Fifteen models were benchmarked, including CNN-Attention, T-JEPA, contrastive learning, graph convolutional network, diffusion-augmented random forest, soft voting ensemble, XGBoost, random forest, SVM-RBF, MLP-ANN, PLS-DA, PCA-DA, HistGB, and LightGBM. Interpretability combined SHAP, attention weights, and hydrogeochemical visualizations.CNN-Attention and soft voting ensemble achieved 89.3% accuracy (25/28, kappa = 0.838); random forest reached 85.7% (24/28). The one-sample difference was not significant (McNemar p = 1.0). T-JEPA and contrastive learning reached 85.7%; XGBoost, PCA-DA, and MLP-ANN reached 82.1%; SVM-RBF and PLS-DA reached 78.6% and 75.0%; HistGB and LightGBM collapsed to 46.4%; the ion-ratio classifier reached 17.9%. SHAP identified Na+K%, Gibbs cation ratio, d-excess, Na/Cl, and HCO3- as dominant discriminants. Removing self-attention reduced accuracy by 3.6 percentage points; halving channels did not alter accuracy. All 86 unlabeled external samples mapped to MW-G, signaling domain shift.Under N = 28, random forest matched complex deep learning methods statistically at lower cost, making it the most cost-effective baseline. Deep learning gains were primarily in auxiliary interpretability. Class-balanced weighting proved essential for small-sample multiclass classification, and the fold-wise leakage-free workflow provides a reproducible methodological reference. The two-sample SW class and absence of an independent external validation set remain the primary limitations.

The induced radioactivity of cooling water is a critical component of accelerator radiation protection. The High-Intensity heavy-ion Accelerator Facility (HIAF), characterized by high particle energy and large beam current, generates strong induced radioactivity in its cooling water, which may pose radiation hazards to personnel and the environment. Therefore, it is necessary to investigate the induced radioactivity of HIAF's cooling water. In this work, a systematic simulation study was performed using the Monte Carlo package FLUKA, combined with the beam loss parameters and the cooling water system design. First, the results indicate that the main radioactive nuclides produced in the cooling water are 15O, 3H, 11C, 7Be and 13N. Second, after 30 years of continuous operation, the radionuclide activity concentration in the cooling water of HIAF's six water stations ranges from 3.29 Bq/g to 9.33× 102 Bq/g, and total activity spans from 5.76× 107 Bq to 1.73× 1010 Bq. In addition, considering the nuclides with γ and β+ radiation, the dose rates around the cooling water pipes of each water station were simulated. At a distance of 30 cm from the pipes, dose rates range from 0.17 μSv/h to 21.67 μSv/h. These rates can be significantly reduced by a 1 cm thick lead shield or 1 h of decay. Finally, the decay tanks were designed to ensure that the radioactive wastewater containing 3H and 7Be could be safely discharged in accordance with relevant standard. This research provides essential data for the radiation safety management of HIAF and serves as a reference for the related studies on similar accelerator facilities.

The Cenozoic potassic-ultrapotassic volcanic rocks are closely related to the formation of the north-south rifts in Tibetan Plateau, which are important objects to study the uplift process of the plateau. We identified a suite of potassic trachyte in the Zuozuoqu of the Shiquanhe in the middle Lhasa subterrane. In order to explore the petrogenesis and tectonic indications of the potassic volcanic rocks, we present detailed chronological, petrographic geochemical and Lu-Hf isotopic geochemistry studies on them. The zircon U-Pb ages of the volcanic rocks are 24.2Ma and 22.3Ma,indicating that the volcanic rocks originally thought to be the Langjiu Formation, Zenong Group should be reclassified as Oligocene. The geochemical characteristics show they have high silicon (64.6% SiO2 <67. 0%)and potassium (6.22% < K2O < 6.53%, 1. 8 < K2O/Na2O < 2.2)contents. They have characteristics of a similar tectonic environment with the potassic rocks exposed in the north-south rifts in the western part of Lhasa terrane, together with adakitic geochemical characteristics such as enrichment of LREEs and LILEs, depletion of HFSEs, high Sr and low Y, high La and low Yb. The low epsilon(Hf)(t) values (-11. 3 similar to-9. 48)suggest that it may have originated from the partial melting of the potassium-rich material the thickened lower crust of the Lhasa terrane in the post-collisional environment. The identification of the potassic rocks in the Zuozuoqu of Shiquanhe (24 similar to 22Ma)provides a basis for the existence of a 'Shiquanhe north-south rift' in the Shiquanhe area in the western Yare Rift, which needs to be further investigated.

The Xinlong gold deposit is a newly discovered epithermal gold deposit of high sulfidation in the continental volcanic rocks of Zenong Group. The study on the genesis and source area of the volcanic rocks in the Zenong Group is of great significance to the search for porphyry-epithermal type deposits in the Central Lhasa subterrane. In this manuscript, the whole-rock geochemistry, chronology and Sr-Nd-Pb-Hf isotope geochemistry of the volcanic rocks of the Zenong Group in the western Dangreyongcuo area have been studied in order to reveal their genetic mechanism and influence on mineralization. The volcanic rocks of the Zenong Group belong to a set of medium-acid volcanic rocks, with andesite, dacite and rhyolite, mainly dacite and rhyolite. Zircon U-Pb age indicates that the volcanic rocks of Zhaliena Formation were formed in 126.3 +/- 1.4Ma, belonging to the Early Cretaceous. The overall characteristics of calc-alkaline to high-K calc-alkaline series (Na2O + K2O = 3.04% similar to 7.24%); Andesite shows quasi-aluminous to weakly peraluminous (A/CNK=0.96 similar to 1.06), dacite and rhyolite show strong peraluminous (A/CNK=1.14 similar to 1.30). The rocks have the characteristics of medium light rare earth total content, light rare earth enrichment and negative Eu anomaly (Sigma REE=94.4x10(-6)similar to 243.2x10(-6), (La/Yb)(N)=5.54 similar to 14.1, delta Eu=0.32 similar to 0.91). The enrichment of LILEs (such as Rb, Th, Pb, etc.) and loss of HFSEs (such as Nb, Ta, Ti, P, etc.), and the depletion of neutral to acidic Eu and HFSEs gradually increased, indicating the fractional crystallization degree of homologous magmas. The volcanic rocks have rich Sr-Nd-Pb isotopic composition ((Sr-87/Sr-86)(i) = 0.71259 similar to 0.72043, epsilon(Nd)(t) = -12.3 similar to-7.89; (Pb-206/Pb-204)(i) = 18.652 similar to 18.718, (Pb-207/Pb-204)(i) = 15.728 similar to 15.770, (Pb-208/Pb-204)(i) = 39.066 similar to 39.336). The Hf isotopic composition is different from that of crustal magma (epsilon(Hf)(t) = -8.55 similar to-0.27). The volcanic rocks of Zhaliena Formation in Zenong Group were formed in arc magmas under the background of oceanic subduction, but different from classical arc magmas, they are generally characterized by strong peraluminous and rich Sr-Nd-Pb isotopes. Based on the geochemical and isotopic characteristics of the whole rock, it is suggested that oceanic floor sediments are the main cause of these geochemical characteristics, indicating that oceanic floor sediments may play an important role in arc magmatism. Meantime, oceanic floor sediments can provide a large amount of fluid, which promotes mantle wedge melting, forming water-rich, high-oxygen fugacity magma conducive to carrying Cu and Au ore-forming elements.

Coal remains a cornerstone of China's energy landscape, significantly contributing to primary energy production and consumption. This study investigates the combustion characteristics of coal particles using a discrete modeling approach to simulate the combustion behavior of single particles. The research reveals that larger particle sizes increase heat and mass transfer resistance, prolonging combustion duration, while higher ambient temperatures enhance convective heat transfer, accelerating combustion reactions. Additionally, the spatial distribution of inert cohesive beads significantly affects gas diffusion, with certain arrangements hindering gas release. The model is validated against current literature, demonstrating its capability to predict carbon conversion rates and combustion dynamics. These findings provide valuable insights into coal combustion mechanisms, offering a foundation for optimizing combustion processes and improving energy efficiency while addressing environmental concerns.

The Zhongshangou deposit, located in the Zhang-Xuan ore concentration area, Hebei Province, China, is a representative Te-rich gold deposit related to alkaline intrusion. For the purpose of revealing the ore-forming characteristics, a comprehensive study was conducted on the ore deposit geology, fluid inclusions, laser Raman spectroscopy, and isotopes of H, O, C, S, and Pb. Fluid inclusion data and laser Raman spectroscopy indicate that the fluids responsible for Au-Te mineralization belong to a H2O-CO2-NaCl system, characterized by medium temperatures and low salinities. The hydrogen (SD =-98.1 %o to-78.7 %o) and oxygen (S18OSMOW =-7.5 %o to 12.5 %o) data suggest that the ore fluids of Zhongshangou were originally magmatic sourced. The S13CV-PDB values of calcite samples (0.7 %o to 1.9 %o) overlap with those of igneous carbon, and the S13CV-PDB values of CO2 extracted from fluid inclusions also show similar characteristics to mantle-derived fluids (-16.9 %o to-13.2 %o). The S34S values of mineralization-associated sulfides have a large range of variations (-19.1 %o to-5.3 %o), implying that the physical and chemical conditions for mineralization have undergone drastic changes. These abrupt fluctuations in ore-forming geochemistry are conducive to anomalous gold enrichment and its coexistence with tellurium. The 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios of mineralization-associated sulfides are 17.24 to 18.08, 15.42 to 15.64, and 37.17 to 38.55, respectively, overlapping with those of deeply sourced alkaline rocks. Similar ore-hosting rocks, mineral assemblages, fluid inclusion types, and comparable stable isotope compositions suggest that the Dongping and Zhongshangou deposits have a common origin and formed in a simultaneous magmatic hydrothermal system.

The Late Triassic arc magmatism in the central Lhasa Terrane holds significant geological importance for understanding the tectonic evolution of the Neo-Tethys Ocean. This study investigates the petrogenesis of the Late Triassic Songmuguo granodiorite and monzogranite in the central Lhasa Terrane through whole-rock geochemical, zircon U-Pb geochronology, and zircon Lu-Hf isotopic analysis. The results show that the zircon U-Pb ages of the Songmuguo granodiorite and monzogranite are 209.7 +/- 1.4Ma and 209.1 +/- 1.5Ma, respectively, indicating their formation during the Late Triassic. The granodiorite exhibits relatively low SiO2 content (63.46%similar to 64.13%) and a Rittmann index (sigma) ranging from 1.97 to 2.84, characteristic of calc-alkaline rocks. In contrast, the monzogranite has higher SiO2 content (72.56%similar to 74.64%) and a Rittmann index (sigma) ranging from 2.19 to 2.39, also displaying calc-alkaline features. The A/CNK values of the granodiorite and monzogranite range from 1.12 to 1.30, indicating strongly peraluminous characteristics. Both rock types are enriched in Rb, U, K, and Th, while being relatively depleted in Nb, P, and Ti. Their (La/Yb)(N) values range from 6.63 to 35.4, reflecting significant fractionation between light and heavy rare earth elements. The study suggests that the monzogranite and granodiorite are strongly peraluminous, calc-alkaline S-type granites. Specifically, the monzogranite originated from the melting of graywacke and felsic pelite, while the granodiorite was derived from the partial melting of the lower crust that had been metasomatized and modified by peraluminous subduction components (e.g., oceanic sediments). Integrating previous research, we propose that the Late Triassic Songmuguo granites in the central Lhasa Terrane formed in a tectonic setting associated with the northward subduction of the Neo-Tethyan Ocean.

The western Dangreyongcuo area, located in the central-northern part of the Central Lhasa terrane, has witnessed a significant breakthrough in lode gold exploration through the recent discovery of the Xinlong gold deposit within continental volcanic sequences. As a key sector for investigating the tectono-thermal evolution of the Central Lhasa terrane, its post-Mesozoic cooling-exhumation processes provide critical constraints on deciphering the Tibetan Plateau uplift dynamics and associated resource-environmental feedbacks. However, this region has received limited systematic investigation to date. This study conducts zircon and apatite (U-Th)/He dating, along with apatite fission track dating, on granites from the Wenbu batholith in western Dangreyongcuo. Integrating these results with the tectonic-thermal evolution of the Lhasa terrane, we reveal the uplift and exhumation history of western Dangreyongcuo since the Mesozoic. Thermochronological data from five samples collected across the eastern and western sectors of the Wenbu batholith yield weighted mean zircon (U-Th)/He ages between 92.7 +/- 3.6 Ma and 62.7 +/- 2.5 Ma, weighted mean apatite (U-Th)/He ages between 53.9 +/- 3.1 Ma and 32.8 +/- 1.1 Ma, and central apatite fission track ages between 63 +/- 3 Ma and 56 f 3 Ma. HeFTy modeling reveals three cooling-exhumation phases in the western Dangreyongcuo region since the Late Cretaceous: I) Rapid cooling stage (95-60 Ma): Cooling and exhumation rates were similar to 2.9 degrees C/Myr and similar to 95.2 m/Myr, respectively, associated with Lhasa-Qiangtang terrane collision and Neo-Tethyan Ocean northward subduction. II) Slow cooling stage (60-35 Ma): Cooling and exhumation rates decreased to similar to 0.8 degrees C/Myr and similar to 26.7 m/Myr, linked to prolonged low-elevation, slow-uplift conditions in the Central Valley. III) Renewed rapid cooling stage (35 Ma-present): Cooling and exhumation rates increased to similar to 1.4 degrees C/Myr and similar to 47.6 m/Myr, related to Lhasa litho-spheric delamination and post-similar to 15 Ma Miocene activity of the Dangreyongcuo Rift, both driven by ongoing India-Eurasia collision. The integration of findings from this study with low-temperature thermochronological data from the Lhasa terrane collectively demonstrates differential evolution between the eastern and central sectors within the Central Lhasa terrane, while the entire Tibetan Plateau interior has undergone significant differential uplift since the Mesozoic. The preservation of the Xinlong high-sulfidation epithermal gold deposit despite intense uplift-denudation primarily resulted from protective burial by post-mineralization Zenong Group volcanic cover and fault-induced thickening of overlying strata caused by normal fault displacement. Prolonged low-elevation conditions and slow uplift rates within the Central Valley during the Eocene enhanced the preservation potential of the orebody.

The accuracy of fossil pollen identification is crucial for understanding past plant diversity, vegetation landscape and associated climate change, while dispersed/fossil pollen assignments heavily rely on how robust modern pollen reference is. There is high species richness in southeastern Tibet, China, however, pollen morphological studies in this area are still poorly documented. Here, we present pollen atlas of 57 species (40 genera, 22 families) collected from the Ranwu Lake Basin. Pollen grains were imaged with light microscope (LM, 100X oil-immersion objective lens) and scanning electron microscope (SEM). All pollen types are ordered and presented according to different aperture types and sculpture patterns, facilitating comparison with fossil pollen. Moreover, we selected some representative species mainly based on potential palaeoecological importance, including Sibiraea (Rosaceae), Koenigia cathayana (Polygonaceae), Stellera chamaejasme (Thymelaeaceae), Hordeum vulgare subsp. vulgare and Poa annua (Poaceae), to discuss their pollen identification characteristics for the first time and assess potential applications in Quaternary palaeoecological interpretation. This study enriches modern pollen atlas for Quaternary pollen analysis in the study area and the adjacent regions. Our results provide robust modern reference in pollen-based reconstruction of vegetation history, palaeoclimate and palaeoenvironment, and tracing pollen signal of local human activities as well.

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Layered materials have attracted extensive attention due to their exceptional physical and chemical properties. Understanding the structural evolution of such materials under high pressure is crucial for the development of new functional materials. In this study, the structure evolution of the synthesized layered rare-earth hydroxyhalide YCl(OH)2 under high pressures up to approximately 9.4 GPa was explored by using a diamond anvil cell combined with synchrotron single-crystal X-ray diffraction. Simultaneously, high-pressure Raman spectroscopy experiment was conducted to 10.3 GPa. Our findings indicate that YCl(OH)2 maintains its symmetry within the experimental pressure range. The pressure-volume data of YCl(OH)2 were fitted to the third-order Birch-Murnaghan equation of state (EoS) to derive its EoS parameters including zero-pressure unit-cell volume (VT0), isothermal bulk modulus (KT0), and its pressure derivative (K'T0): VT0 = 142.47 (1) Å3, KT0 = 38.2 (18) GPa, and K'T0 = 9.8 (1). However, the unit-cell parameters a, b, and c exhibit a distinct compressional behavior, with the a-axis being the most compressible and the b-axis being the least. Particularly noteworthy is the observation that YCl(OH)2 displays a negative linear compressibility along the b-axis within the pressure range of 0.4-5.3 GPa. Further detailed structure refinement and Raman spectroscopy analyses indicate that the anomalous behavior of the b-axis could be attributed to the formation of the O-H···O hydrogen bonding chains along the b direction. Moreover, the coordination number of Y3+ increased from 8 to 9 as the pressure reached 5.3 GPa due to the reduction of the interlayer spacing upon compression, ultimately leading to the closure of the interlayer gap.

The Advanced Space- based Solar Observatory (ASO-S) was successfully sent to space from Jiuquan Launch center on Oct. 9, 2022. The ASO- S is dedicated to study solar flares, corneal mass eruptions and their connections with solar magnetic field and configured three instruments: a Full-disk solar vector MagnetoGraph (FMG), a Lyman- alpha Solar Telescope (LST), and a solar Hard X-ray Imager (HXI). Until Dec. 2023, the ASO-S has smoothly operated at 720 kilometers above Earth's surface in a Sun-synchronous orbit for one more year. The HXI is one of the three key parts in this mission and adopts a spatial modulation technique to indirectly achieve image of solar hard X-rays. It is made up of a collimator, a spectrometer and an electrical control box. As the critical component, the collimator is responsible for incident X-ray modulation. This paper presents detailed design of HXI, especially the core part -- collimator. Secondly, ground tests, including characterization and spatial environmental tests of HXI collimator will be reported accounted for its indirect imaging principle. We will put forward some newly on-orbit results in the past one year. All design and test result as well as on orbit performance verifies that this equipment fully completed its expected goal and even presents a more wonderful status over expectations.

Genetic classification of sediment-hosted Au deposits is often disputed in many orogenic belts around the world. The marine sediment-hosted Qukuleke Au deposit (>5 t Au) is an example of this, which has been attributed to orogenic or intrusion-related type. This paper addresses its metallogeny through detailed geologic and petrographic studies, together with apatite U-Pb dating and C-O-S-Pb isotopes. The hydrothermal paragenesis at Qukuleke is divided into three stages (I to III): Stage I (pre-ore) sheeted quartz veins; Stage II (main ore) pervasive sericite +/- carbonate +/- apatite +/- pyrite +/- arsenopyrite alteration associated with quartz-calcite +/- stibnite veins; Stage III (post-ore) barren calcite veins. LA-ICP-MS hydrothermal apatite U-Pb dating on Stage II disseminated Au ore yielded 208.1 +/- 6.5 Ma, coeval with the Late Triassic post-collisional intrusions from the periphery of Qukuleke deposit. Carbon-oxygen isotopes of Au-Sb ore-related hydrothermal calcite show that the hydrothermal fluids were derived from the marine carbonate ore host with considerable magmatic input. Lead-sulfur isotopes of the Au-Sb ore-related are consistent with those of coeval intrusions around the deposit, but different from those of the local sedimentary strata. Our age and geochemical data suggest the presence of a magma source that supplied the hydrothermal fluids, sulfur and metals for the mineralization. Combining the low sulfide content and the Au-As-W-Sb-Mo assemblage characteristics, the Qukuleke is best classified as a sediment-hosted intrusion-related Au deposit. Considering also the discovery of the large coeval Qukukekedong Au deposit nearby, we propose that Late Triassic intrusion-related Au system is a high-potential exploration target in the western EKOB.

The Middle Miocene Zhangpu biota (similar to 14.7 Ma)-from the Fotan Formation in the Zhangpu area, southeastern China-indicates that the rainforest had reached at least 24.2 degrees N at that time. In this study, pollen analysis was carried out in six outcrop sections of this formation in the Zhangpu area. Based on the succession of palynoflora, three developmental stages of vegetation were recognized. From the late Early Miocene to the Middle Miocene Climatic Optimum (MMCO) (the first stage), the vegetation underwent frequent disturbances associated with the volcanic activities, in which two sub-stages are recognizable. During the earlier sub-stage (late Early Miocene), the vegetation was similar to the modern subtropical evergreen broad-leaved forest and exhibited a warming trend; then during the later sub-stage (MMCO), the tropical forest developed with the appearance of diverse tropical and subtropical taxa. The second stage, which was also within the MMCO, should be an intermission of volcanic eruptions, during which the tropical forest, especially the tropical montane rain forest, steadily developed without disruptions. And during the third stage (Middle to Late Miocene), the altitudinal vegetation belts of tropical montane rain forest significantly lowered which was accompanied by the occurrence of drought-tolerant taxa, implying the significant climatic cooling and moisture reduction. The above evolutionary phases of the vegetation in the Zhangpu area show a close relationship with the Miocene global climatic variations, which might be the main driving force of the vegetation changes in the southeast coast area of China during that period.

The Xinlong gold deposit is located in Niyma County, Naqu area of Tibet and was discovered by the Institute of Mineral Resources, Chinese Academy of Geological Sciences through the 1∶50000 mineral geological survey. The ore bodies occur in the Zenong Group volcanic rocks in the middle section of the central Lhasa subterrane and are structurally controlled by the NNW-striking faults. Four ore bodies have been found, exhibiting cloddy, dense-sparse, disseminated, and breccia structures. The ore minerals are mainly tetrahedrite group minerals, and other ore minerals include pyrite, chalcopyrite, nevskite, bornite, anglesite, native gold, and silver-gold bearing selenide, etc. The types of alteration are dominated by silicification, as well as middle- and high-graded argillization. The alteration mineral assemblages contain quzrtz, pyrophyllite, and kaolinite. The Zaliela Formation volcanic rocks of Zenong Group are silicified by later hydrothermal fluid with vuggy quartz in some fractured zones. The middle- and high-graded argillization are characterized by pyrophyllitization and kaolinization. The Xinlong gold deposit shows great metallogenetic potentiality and has been revealed by 1∶10000 geological mapping, IP sounding, and trial trenching in the mining area. Combined with the regional metallogenic geological setting, we suppose that a potential epithermal gold belt probably exists in the middle of the Lhasa terrane. The discovery of the Xinlong gold deposit opens a new chapter for the gold prospecting in Northern Tibet.