(1) Mineralization Mechanisms: Based on geological observations (such as fluid inclusion petrography, composition analysis, and recovery of entrapment conditions), we design and conduct specialized online high-temperature and high-pressure experiments to simulate the magmatic-hydrothermal processes. This helps identify the migration and concentration mechanisms of mineralizing elements during the magmatic-hydrothermal transition and hydrothermal stages. Currently, we focus on W-Sn rare metal deposits related to granites, carbonatite-type REE deposits, and pegmatite-type Li deposits in South China.

(2) Experimental Geochemistry: We innovate and develop visualization and online high-temperature high-pressure experimental methods (hydrothermal diamond anvil cells, cold-sealed high-pressure vessels) to simulate the T-P-x conditions of the crust and upper mantle (21 - 1000 °C, 0.1 - 3 GPa). This work reveals the thermodynamic properties of fluids and melts, providing fundamental experimental constraints for studies on diagenesis and mineralization. Using fused silica capillary tube techniques for synthesizing inclusions, we establish in-situ Raman spectroscopy methods for quantitative analysis of geological fluids (including salinity, S, B, and C-H-O-S-N volatiles) and analyze typical diagenetic and mineralizing systems to reconstruct the paleo-temperature and pressure fields influenced by fluid activities, thereby recovering geological processes.

(3) Petroleum Geology: Currently, we mainly focus on the evolution pathways and controlling factors of hydrocarbon phase states (studies on diagenesis, fluid inclusion analysis, and high-temperature high-pressure simulation experiments) to reveal the conditions and mechanisms for hydrocarbon preservation. We investigate the evolution of paleo-temperature and pressure fields in sedimentary basins, especially the origin, preservation mechanisms, and geological significance of strongly overpressured fluids, as well as the interactions between organic and inorganic materials in sedimentary basins.

[58] Liu W., Hu W.*, Zhang W., Wang X., Cao J., Luo X., An S., Li W., Zhi D., Li W. (2024) 13C-enriched carbonate precipitates reveal intense methanogenic oil degradation in the upper Wuerhe Formation, Northwest China. Geology, https://doi.org/10.1130/G52293.1

[57] Wan Q., Wang X.*, Hu W., Wan Y., Chou I-M. (2024) Reaction pathway, mechanism and kinetics of thermochemical sulfate reduction: insights from in situ Raman spectroscopic observations at elevated temperatures and pressures. Geochimica et Cosmochimica Acta, 381, 25-42.

[56]  Sun D., Wang X.*, Li F., Hu W., Cao J., You D., Xi B. (2024) Fluid inclusion records of oil-cracked wet gas in Permian carbonate reservoirs from the Eastern Sichuan Basin, China. Marine and Petroleum Geology, 164, 106831.

[55] Li F., Wan Y., Sun D., Wang X.*, Hu W. (2024) Determination of the pressure and composition of wet gas fluid inclusions: An in situ Raman spectroscopic approach. Spectrochimia Acta Part A: Molecular and Biomolecular Spectroscopy, 308: 123774

[54] Sun F., Hu W.*, Wang X., Hu Z., Wu H., Guo Y., Wei G. (2023) Methanogen-mediated dolomite precipitation in an early Permian lake in northwestern China. GSA Bulletin, https://doi.org/10.1130/B37156.1

[53] Wan Y., Chou I-M.*, Wang X*, Wang R., Li X. (2023) Hydrothermal sulfate surges promote rare earth element transport and mineralization. Geology, 51, 449-453, doi: 10.1130/G50848.1 

[52] Lu W., Wang X.*, Wan Q., Hu W., Chou I-M., Wan Y. (2023) In situ Raman spectroscopic measurement of the 13C/12C ratio in CO2: Experimental calibrations on the effects of fluid pressure, temperature and composition. Chemical Geology,  615, 121201, doi: https://doi.org/10.1016/j.chemgeo.2022.121201

[51] Zuo Z., Cao J.*, Hu W., Shi C., Wang X., Yao S., Luo B. (2022) Characterizing the maturity of highly evolved organic matter based on aromatic hydrocarbons and optimization with pyrobitumen reflectance and Raman spectral parameters. Science China Earth Sciences, https://doi.org/10.1007/s11430-022-9955-7

[50] Qiu Y., Wang X.*, Lu J., Chou I-M., Wan Y., Zhang R., Zhang W., Sun R. (2022) In situ observations of tungsten speciation and partitioning behavior during fluid exsolution from granitic melt. Sci. Bull., 67: 2358-2368, doi: https://doi.org/10.1016/j.scib.2022.10.024

[49] Sun F., Hu W., Cao J., Wang X., Zhang Z., Ramezani J., Shen S. (2022) Sustained and intensified lacustrine methane cycling during Early Permian climate change. Nature Communications, 13(1): 4856

[48] Zuo Z., Cao J., Wang X., Luo B., Zhong Y., Li K., Hu K. (2022) Characterizing maturity of reservoir pyrobitumen with strong anisotropy: A calibration between reflectance and laser Raman spectral parameters. AAPG Bulletin, 106: 1373-1401.

[47] Wang X.*, Hu W., Qiu Y., Liu Y., Jia D., Cao J., Liu X., Li Y.* (2022) Fluid inclusion evidence for extreme overpressure induced by gas generation in sedimentary basins. Geology, 50: 765-770. Doi: 10.1130/G49848.1

[46] Wu H., Hu W., Wang Y., Tao K., Tang Y., Cao J., Wang X., Kang X. (2021) Depositional conditions and accumulation models of tight oils in the middle Permian Lucaogou Formation in Junggar Basin, northwestern China: New insights from geochemical analysis. AAPG Bulletin, 105(12): 2477-2518.

[45] Yang S., Hu W.*, Wang X., Fan J. (2021) Nitrogen isotope evidence for a redox-stratified ocean and eustasy-driven environmental evolution during the Ordovician-Silurian transition. Global and Planetary Change, 207, 103682. https://doi.org/10.1016/j.gloplacha.2021.103682

[44] Wan Y., Chou I-M.*, Wang X.*, Sun X. (2021) Explorations on footprints of salt-rich fluid and salt-depleted fluid immiscibility in hydrothermal systems: Insights from divergent partitioning of sulfate and perchlorate in the ZnSO4-Zn(ClO4)2-H2O system. Chemical Geology, 584: article no. 120520.

[43] Cui H., Zhong R.*, Xie Y., Wang X.*, Chen H. (2021) Melt–Fluid and Fluid–Fluid Immiscibility in Na2SO4–SiO2–H2O System and Its Implications for the Formation of Rare Earth Deposits. Acta Geologica Sinica (English Edition), 10.1111/1755-6724.14795.

[42] Wan Y., Wang X*, Chou I-M.*, Li X. (2021) Role of sulfate in the transport and enrichment of REE in hydrothermal systems. Earth and Planetary Science Letters, 569: article no. 117068.

[41] Yu Y., Hu W.*, Chou I-M., Jiang L., Wan Y., Li Y., Xin Y., Wang X.* (2021) Species of sulfur in sour gas reservoir: Insights from in situ Raman spectroscopy of S-H2O-CH4-H2O system and its subsystems from 20 to 250 C. Geofluids, 2021: 6658711

[40] Qiu Y., Zhang R., Chou I-M., Wang X.*, Hu W., Zhang W., Lu J., Li G., Li Z. (2021) Boron-rich ore-forming fluids in hydrothermal W-Sn deposits from South China: insights from in situ Raman spectroscopic characterization of fluid inclusions. Ore Geology Reviews, 132: 104048 https://doi.org/10.1016/j.oregeorev.2021.104048

[39] Xie D., Yao S.*, Cao J., Hu W., Wang X., Zhu N. (2021) Diagenetic alteration and geochemical evolution during sandstones bleaching of deep red-bed induced by methane migration in petroliferous basins. Marine and Petroleum Geology, 127: 104940

[38] Yang S., Hu W.*, Wang X. (2021) Mechanism and implications of upwelling from the late Ordovician to early Silurian in the Yangtze region, South China. Chemical Geology, 565: 120074. DOI:10.1016/j.chemgeo.2021.120074

[37] Kang X., Hu W., Tan J., Li Z., Xiang B., Wang J., Wang X. (2021) Hydrogen isotopic responses to thermochemical oxidation of light hydrocarbon gases in deep clastic reservoirs of the Junggar Basin, China. Chemical Geology, 563: 120052.

[36] Sun F., Hu W., Wu H., Fu B., Wang X., Tang Y., Cao J., Yang S., Hu Z. (2021) Two-stage mineral dissolution and precipitation related to organic matter degradation: Insights from in situ C–O isotopes of zoned carbonate cements. Marine and Petroleum Geology, 124: article no. 104812

[35] Wang X.*, Wan Y., Chou I-M. (2021) Fate of sulfate in seafloor hydrothermal systems: Insights from in situ observation of the liquid-liquid phase separation in hydrothermal fluids. Solid Earth Sciences,  https://doi.org/10.1016/j.sesci.2020.12.001

[34] Wan Y., Bourdet J., Hu W., Kang X., Heath C., Qiu Y., Gao W., Wang X*. (2021) Experimental investigation on the thermochemical oxidation of n-alkane and alcohol compounds by MnO2 and Fe2O3 at temperatures up to 325 C. Chemical Geology, 559: article no. 119982. 

[33] Sun F., Hu W.*, Wang X., Cao J., Fu B., Wu H., Yang S. (2021) Methanogen microfossils and methanogenesis in Permian lake deposits. Geology, 49: 13-18.

[32] Wang X.*, Qiu Y., Chou I-M., Zhang R., Li G., Zhong R. (2020) Effects of pH and salinity on the hydrothermal transport of tungsten: Insights from in situ Raman spectroscopic characterization of K2WO4-NaCl-HCl-CO2 solutions at temperatures up to 400 C. Geofluids, article ID 2978984, p1-12

[31] Qiu Y., Yang Y., Wang X.*, Wan Y., Hu W., Lu J., Tao G., Li Z., Meng F. (2020) In situ Raman spectroscopic quantification of aqueous sulfate: Experimetal calibration and application to natural fluid inclusions. Chemical Geology, 533: article no. 119447.

[30] Wang X.*, Qiu Y., Lu J., Chou I-M., Zhang W., Li G., Hu W., Li Z., Zhong R.* (2020) In situ Raman spectroscopic investigation of the hydrothermal speciation of tungsten: Implications for the ore-forming process. Chemical Geology, 532: article no. 119299.

[29] Wang L., Hu W.*, Wang X.*, Cao J., Yao S. (2020)  Halogens (Cl, Br, I) geochemistry in Middle Triassic carbonates: Implications for salinity and diagenetic alteration of I/(Ca + Mg) ratios. Chemical Geology, 533: article no. 119444.

[28] Qiu Y., Wang X.-L.*, Liu X., Cao J., Liu Y.-F., Xi B.-B., Gao W.-L. (2020) In situ Raman spectroscopic quantification of CH4-CO2 mixture: application to fluid inclusions hosted in quartz veins from the Longmaxi shales in Sichuan Basin, southwestern China. Petroleum Science, 17: 23 - 25 (Cover article).

[27] Chang C.*, Hu W., Wang X., Huang K.-J., Yang A., Zhang X. (2019) Nitrogen isotope evidence for an oligotrophic shallow ocean during the Cambrian Stage 4. Geochim. Cosmochim. Acta, 257: 49 - 67.

[26] Yang S., Hu W.*, Wang X., Jiang B., Yao S., Sun F., Huang Z., Zhu F. (2019) Duration, evolution, and implications of volcanic activity across the Ordovician-Silurian transition in the Lower Yangtze region, South China.Earth Planet. Sci. Lett., 518: 13 - 25.

[25] Hu W.-X., Kang X., Cao J., Wang X.-L., Fu B., Wu H.-G. (2018) Thermochemical oxidation of methane induced by high-valence metal oxides in a sedimentary basin. Nature Commumications, 2018(9): 5131.  

[24] Hu W.*, Wang X., Zhu D., You D., Wu H. (2018) An overview of types and characterization of hot fluids associated with reservoir formation in petroliferous basins. Energy Exploration & Exploitation, 36: 1359 – 1375.

[23] Chang C., Hu W., Fu Q., Cao J., Wang X., Wan Y., Yao S. (2018) Characteristics and formation processes of (Ba, K, NH₄)-feldspar and cymrite from a lower Cambrian black shale sequence in Anhui Province, South China. Mineralogical Magazine, DOI: https://doi.org/10.1180/minmag.2017.081.017.

[22] Wang X.*, Song Y., Chou I-M.*, Qiu Y. (2018) Raman spectroscopic characterization of cracking and hydrolysis of n-pentane and n-octadecane at 300 - 375 C with geological implications.Energy Exploration & Exploitation, doi: 10.1177/0144598717748762.

[21] Chang C., Hu W., Wang X., Yu H., Yang A., Cao J., Yao S. (2017) Carbon isotope stratigraphy of the lower to middle Cambrian on the eastern Yangtze Platform, South China. Palaeogeography, Palaeoclimatology, Palaeoecology 479, 90-101

[20] Wu H., Hu W., Tang Y., Cao J.,Wang X., Wang Y., Kang X. (2017) The impact of organic fluids on the carbon isotopic compositions of carbonate-rich reservoirs: case study of the Lucaogou Formation in the Jimusaer Sag, Junggar Basin, NW China. Marine and Petroleum Geology85, 136-150.

[19] Wan Y.,Wang X.*, Chou I-M., Hu W., Zhang Y., and Wang X. (2017) An Experimental Study of the Formation of Talc through CaMg(CO3)2–SiO2–H2O Interaction at 100–200°C and Vapor-Saturation Pressures. Geofluids, 3942826, 1-14. doi:10.1155/2017/3942826.

[18] Wan Y., Wang X.*, Hu W., Chou I-M., Wang X., Chen Y., Xu Z. (2017) In situ optical and Raman spectroscopic observations of the effects of pressure and fluid composition on liquid–liquid phase separation in aqueous cadmium sulfate solutions (
400
C, 50 MPa) with geological and geochemical implications. Geochimica et Cosmochimica Acta 211, 133-152.

[17] Wang X.*, Wang X., Chou I-M., Hu W., Wan Y., and Li Z. (2017) Properties of lithium under hydrothermal conditions revealed by in situ Raman spectroscopic characerization of Li2O-SO3-H2O(D2O) systmes at temperatures up to 420 C. Chemical Geology 451, 104-115.

 [16] Wang X., Wang X.*, Hu W., Wan Y., Cao J., Lv C., Wang R., Cui M. (2017) Supercritical CO2-involved water-rock interactions at 85 C and partial pressures of 10-20 MPa: Sequestration and enhanced oil recovery. Energy Exploration & Exploitation, 35(2): 237-258.

[15] WangX.*, Wan Y., Hu W., Chou I-M., Cao J., Wang X., Wang M. and Li Z. (2016) In situ observations of liquid–liquid phase separation in aqueous ZnSO₄ solutions at temperatures up to 400° C: Implications for Zn²⁺–SO₄²⁻ association and evolution of submarine hydrothermal fluids. Geochimica et Cosmochimica Acta 181, 126-143.

[14] WangX.*, Chou I.M., Hu W., Yuan S., Liu H., Wan Y. and Wang X. (2016) Kinetic inhibition of dolomite precipitation: Insights from Raman spectroscopy of Mg²⁺–SO₄²⁻ ion pairing in MgSO₄/MgCl₂/NaCl solutions at temperatures of 25 to 200° C. Chemical Geology 435, 10-21.

[13] WangX.*, Wan Y., Hu W., Chou I-M., Cai S., Lin N., Zhu Q. and Li Z., (2016) Visual and in situ Raman spectroscopic observations of the liquid–liquid immiscibility in aqueous uranyl sulfate solutions at temperatures up to 420° C. The Journal of Supercritical Fluids 112, 95-102.

[12] Wu H., Hu W., Cao J., Wang X., Wang X., Liao Z. (2016) A unique lacustrine mixed dolomitic-clastic sequence for tight oil reservoir within the middle Permian Lucaogou Formation of the Junggar Basin, NW China: Reservoir characteristics and origin. Marine and Petroleum Geology 76, 115-132.

[11] Chang C., Hu W., Fu Q., Cao J., Wang X. and Yao S. (2016) Characterization of trace elements and carbon isotopes across the Ediacaran-Cambrian boundary in Anhui Province, South China: Implications for stratigraphy and paleoenvironment reconstruction. Journal of Asian Earth Sciences 125, 58-70.

[10] Liao Z., Hu W., Cao J., Wang X., Yao S. and Wan Y. (2016) Permian–Triassic boundary (PTB) in the Lower Yangtze Region, southeastern China: A new discovery of deep-water archive based on organic carbon isotopic and U–Pb geochronological studies.Palaeogeography, Palaeoclimatology, Palaeoecology 451, 124-139.

[9] Liao Z., Hu W., Cao J., Wang X., Yao S., Wu H. and Wan Y. (2016) Heterogeneous volcanism across the Permian–Triassic Boundary in South China and implications for the Latest Permian Mass Extinction: New evidence from volcanic ash layers in the Lower Yangtze Region. Journal of Asian Earth Sciences 127, 197-210

[8] Wan Y., WangX.*, Hu W. and Chou I-M. (2015) Raman Spectroscopic Observations of the Ion Association between Mg²⁺ and SO₄^2– in MgSO₄-Saturated Droplets at Temperatures of ≤ 380° C. The Journal of Physical Chemistry A 119, 9027-9036.

[7] Wang L., Hu W.*, Wang X., Cao J., Chen Q., Seawater normalized REE patterns of dolomite in Geshan and Panlongdong sections, China: Implications for tracing dolomitization and diagenetic fluids, Marine and Petroleum Geology, 2014, 56: 63-73

[6] Yuan S., Chou I.-M., Burruss R.C.,Wang X., and Li J. (2013) Disproportionation and thermochemical sulfate reduction reactions in S-H2O-CH4 and S-D2O-CH4 systems from 200 to 300 C. Geochimica et Cosmochimica Acta118, 263-275. 

[5] Wang X.*, Hu W., and Chou I.-M. (2013) Raman spectroscopic characterization on the OH stretching bands in NaCl-Na2CO3-Na2SO4-CO2-H2O systems: Implications for the measurement of chloride concentrations in fluid inclusions. Journal of Geochemical Exploration132, 111-119.

[4] Wang X.*,  Chou I.-M., Hu W., and Burruss R.C. (2013) In-situ observations of liquid-liquid phase separation in aqueous MgSO4 solutions. Geochimica et Cosmochimica Acta103, 1-10.

[3] Wang X.*,  Chou I.-M., Hu W., Burruss R.C., Sun Q. and Song Y. (2011) Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations. Geochimica et Cosmochimica Acta75, 4080-4093.

[2] Wang X.,  Hu W., Yao S., Chen Q. and Xie X. (2011) Carbon and strontium isotopes and global correlation of Cambrian Series 2-Series 3 carbonate rocks in the Keping area of the northwestern Tarim Basin, NW China. Marine and Petroleum Geology28, 992-1002.

[1] Wang X.,Jin Z., Hu W., Zhang J., Qian Y., Zhu J. and Li Q. (2009) Using in situ REE analysis to study the origin and diagenesis of dolomite of Lower Paleozoic, Tarim Basin. Science in China Series D-Earth Sciences 52, 681-693.