100. Yan, W., Lv, M., He, M., Liu, X. (2022). Effect of second Si-O vibrational overtones/combinations on quantifying water in silicate and silica minerals using infrared spectroscopy, and an experimental method for its removal. Physics and Chemistry of Minerals (In press; Corresponding Author).
99. Mi, Z., Bao, X., Tan, D., Shi, W., Zhang, L., Liu, X. (2022). Equation of state of a new calcium magnesium silicate compound with the composition Ca3MgSi2O8 at pressures up to 23 GPa and ambient T. Physics and Chemistry of Minerals (10.1007/s00269-021-01175-1; Corresponding Author).
98. Ma, Y., Bao, X., Sui, Z., Zhao, X., Liu, X. (2022). Quantifying Mg-Al cation distribution in MgAl2O4-spinel using Raman spectroscopy: an experimental calibration. Solid Earth Sciences (10.1016/j.sesci.2021.09.002; Corresponding Author).
97. Li, H., Zhang, L., Bao, X., Wykes, JL, Liu, X. (2021). High sulfur solubility in subducted sediment melt under both reduced and oxidized conditions: with implications for S recycling in subduction zone setting. Geochimica et Cosmochimica Acta 304, 305-326.
96. Ma, Y., Bao, X., Liu, X. (2021). Thermodynamics of Mg-Al order-disorder reaction in MgAl2O4-spinel: constrained by prolonged annealing experiments at 773-1123 K. Molecules 26, 872 (Corresponding Author).
95. Yan, W., Liu, X., Sun, S., Sun, W., Wu, D. (2021). Experimental constraints on trace element partitioning between coesite and hydrous silicate melt at 5 GPa and 1500-1750 oC. China Science Earth Sciences 64, 1171-1183 (Corresponding Author)
94. Ma, Y., Yan, W., Sun, Q., Liu, X. (2021). Raman and infrared spectroscopic quantification of the carbonate concentration in K2CO3 aqueous solutions with water as an internal standard. Geoscience Frontiers 12, 1018-1030 (Corresponding Author).
93. Bao, X., He, M., Zhang, Z., Liu, X. (2021). Crystal structure and some thermodynamic properties of Ca7MgSi4O16-bredigite. Crystals 11, 14 (Corresponding Author).
92. Yan, W., Zhang, Y., Ma, Y., He, M., Zhang, L., Sun, W., Wang, CY, Liu, X. (2021). On the water in coesite: its incorporation mechanism, quantification method, solubility and P-T dependence, and influence on coesite preservation. Geoscience Frontiers 12, 313-326 (Corresponding Author).
91. 嚴薇,劉曦 (2021). 名義上無水礦物中水的定量方法及其優缺點-FTIR方法及其存在問題. 礦物岩石地球化學通報 40, 425-447 (Corresponding Author).
90. Liu, X. (2020). Compositional characteristics of ringwoodite in the lower part of the mantle transition zone. Solid Earth Sciences 5, 223-225.
89. Tao, R., Zhang, L., Liu, X., Li, S. (2020). Experimental study of trace element mobility during dehydration of lawsonite blueschist along different P-T paths: Implications for geochemical heterogeneity of Earth’s mantle. Journal of Asian Earth Sciences 197, 104389.
88. Liu ,X., Sui, Z., Fei, H., Yan, W., Ma, Y., Ye, Y. (2020). IR features of hydrous Mg2SiO4-ringwoodite, unannealed and annealed at 200-600 oC and 1 atm, with implications to hydrogen defects and water-coupled cation disorder. Minerals 10, 499.
87. Wang, C-P, Shieh S.R, Withers,AC, Liu, X., Zhang, D., Tkache ,SN, Djirar A-E, Xie, T., Rumney, JD. (2020). Raman and X-ray diffraction study of pressure-induced phase transition in synthetic Mg2TiO4. Scientific Reports 10, 6278.
86. Wang, Y., He, M., Yan, W., Yang, M., Liu, X. (2020). Jianite: massive dunite solely made of virtually pure forsterite from Ji'an County, Jilin Province, Northeast China. Minerals, 10, 220 (Corresponding Author).
85. Wang, M., Deng, J., Hou, T., Derrey, I.T., Botcharnikov, R.E., Liu, X., Zhang, C., Qi, D., Zhang, Z., Holtz, F. (2020). Experimental evidence for a protracted enrichment of tungsten in evolving granitic melts: implications for scheelite mineralization. Mineralium Deposita (10.1007/s00126-019-00932-1).
84. Wang, Y., Sun, Q., Duan, F., Bao, X., Liu, X. (2019). The study of crystal structure on grossular-andradite solid solution. Minerals, 9, 691 (Corresponding Author).
83. Liu, L., Ma, Y., Yan, W., Liu, X. (2019). Trace element partitioning between MgAl2O4-spinel and carbonatitic silicate melt from 3 to 6 GPa, with emphasis on the role of cation order-disorder. Solid Earth Sciences, 4, 43-65 (Corresponding Author).
82. Ma, Y., Liu, X. (2019). Kinetics and thermodynamics of Mg-Al disorder in MgAl2O4-Spinel: A Review. Molecules, 24, 1704 (doi:10.3390/molecules24091704; Corresponding Author).
81. Zhang, Y., Zhang, Y., Liu,Y., Liu, X. (2019). A metastable Fo-III wedge in cold slabs subducted to the lower part of the mantle transition zone: A hypothesis based on first-principles simulations. Minerals, 9, 186 (doi:10.3390/min9030186; Corresponding Author).
80. He, M., Yan, W., Chang, Y., Liu, K., Liu, X. (2019). Fundamental infrared absorption features of α-quartz: An unpolarized single-crystal absorption infrared spectroscopic study. Vibrational Spectroscopy, 101, 52-63.
79. Zhang, Y., Liu, X., Shieh, S.R., Zhang, Z., Bao, X., Xie, T., Wang, F., Prescher, C., Prakapenda, V.B. (2019). Equations of state of Co2TiO4-Sp, Co2TiO4-CM, and Co2TiO4-CT, and their phase transitions: an experimental and theoretical study. Physics and Chemistry of Minerals, doi.org/10.1007/s00269-019-01023-3.
78. Mi, Z., Shi, W., Zhang, L., Shieh, S.R., Liu, X. (2018). Equation of state of a natural chromian spinel at ambient temperature. Minerals, 8, 591 (doi:10.3390/min8120591;).
77. Tao, R., Zhang, L., Tian, M., Zhu, J., Liu, X., Liu, J., Hofer, H., Stagno ,V., Fei, Y. (2018). Formation of abiotic hydrocarbon from reduction of carbonate in subduction zones: Constraints from petrological observation and experimental simulation. Geochimica et Cosmochimica Acta, 239, 390–408.
76. Zhang,Z., Mao, Z., Liu, X., Zhang, Y., Brodholt, J. (2018). Stability and reactions of CaCO3 polymorphs in the Earth’s deep mantle. Journal of Geophysical Research, 10.1029/2018JB015654.
75. Liu, L., Hu, X., Liu, X. (2018). MgO partition between olivine and K2O-rich silicate melt: Geothermometers applicable to high potassium magmas. Journal of Asian Earth Sciences, 166,181–194.
74. 陳濤,王一川,暴新建,馬雲璐,劉麗萍,劉曦(2018)。大壓機高壓實驗中的加熱方法、溫度測量與實驗組裝中的溫度分布。地球科學與環境學報40,428-448。
73. Liu, L., Liu, X., Bao, X., He, Q., Yan, W., Ma, Y., He, M., Tao, R., Zou, R. (2018). Si-Disordering in MgAl2O4-Spinel under High P-T Conditions, with Implications for Si-Mg Disorder in Mg2SiO4-Ringwoodite. Minerals, 8, 210.(doi:10.3390/min8050210).
72. Sun, W., Hawkesworth, C.J., Yao, C., Zhang, C., Huang, R., Liu, X., Sun, X., Ireland, T., Song, M., Ling, M., Ding, X., Zhang, Z., Fan, W., Wu, Z. (2018). Carbonated mantle domains at the base of the Earth’s transition zone. Chemical Geology ,478, 69-75.
71. Du, W., Han, B., Clark, S.M., Wang, Y., Liu, X. (2018). Raman spectroscopic study of synthetic pyrope-grossular garnets: structural implications. Physics and Chemistry of Minerals, 45, 197-209.
70. Bao, X., Liu, X., Liu, X. (2017). High-pressure synthesis, crystal structure and photoluminescence properties of a new terbium silicate: Na2Tb1.08Ca2.92Si6O18H0.8. RSC Advances, 7, 50195-50199. (Corresponding Author).
69. 劉曦,代立東,鄧力維,範大偉,劉瓊,倪懷玮,孫樯,巫翔,楊曉志,翟雙猛,張寶華,張莉,李和平(2017)。近十年我國在地球内部物質高壓物性實驗研究方面的主要進展。高壓物理學報,31, 657-681。
68. Bao, X., Zhang, Y., Zhang, Z., Zhang, L., Liu, X., Dong, J., Liu, X. (2017). A new Ca3MgSi2O8 compound and some of its thermodynamic properties. Journal of Solid State Chemistry, 255, 145-149 (Corresponding Author).
67. Tao, R., Zhang, L., Liu, X., Bader, T., Fei, Y. (2017). Phase relations and formation of K-bearing Al-10 A phase in the MORB + H2O system: implications for the H2O- and K-cycle in subduction zone. American Mineralogist, 102, 1922-1933.
66. Tao, R., Zhang, L., Stagno, V., Chu, X., Liu, X. (2017). High-pressure experimental verification of rutile-ilmenite oxybarometer: implications for the redox state of the subduction zone. Science China-Earth Sciences, 60, 1817-1825.
65. Liu, X., Ma, Y., He, Q., He, M. (2017). Some IR features of SiO4 and OH in coesite, and its amorphization and dehydration at ambient pressure. Journal of Asian Earth Sciences,148, 315-323 (Corresponding Author).
64. Xu, C., Kynicky, J., Tao, R., Liu, X., Zhang, L., Pohanka, M., Song, W., Fei, Y. (2017). Recovery of an oxidized majorite inclusion from Earth's deep asthenosphere. Science Advances, 3, e1601589.
63. Zhang, Y., Liu, X., Shieh, S.R., Bao, X., Xie, T., Wang, F., Zhang, Z., Prescher, C., Prakapenka, V.B. (2017). Spinel and post-spinel phase assemblages in Zn2TiO4, an experimental and theoretical study. Physics and Chemistry of Minerals, 44, 109-123 (Corresponding Author).
62. Liu, X., Xiong, Z., Shieh, S.R., He, Q., Deng, L., Zhang, Y., Chang, L., Wang, F., Hong, X., Chen, Z. (2016). Non-monotonic compositional dependence of isothermal bulk modulus of the (Mg1-xMnx)Cr2O4 spinel solid solutions, and its origin and implication. Solid Earth Sciences, 1, 89-100 (Corresponding Author).
61. He, Q., Liu, X., Li, B., Deng, L., Liu, W., Wang, L. (2016). Thermal equation of state of a natural kyanite up to 8.55 GPa and 1273 K. Matter and Radiation at Extremes, 1, 269-276 (Corresponding Author).
60. Zhang, Y., Liu, X., Xiong, Z., Zhang, Z. (2016). Compressional behavior of MgCr2O4 spinel from first-principles simulation. Science China D: Earth Sciences ,59, 989-996 (Corresponding Author).
59. Lv, M., Liu, X., Shieh, S.R., Xie, T., Wang, F., Prescher, C., Prakapenka, V.B. (2016) Equation of state of synthetic qandilite Mg2TiO4 at ambient temperature. Physics and Chemistry of Minerals, 43,301-306(Corresponding Author).
58. Xiong Z, Liu X, Shieh SR, Wang S, Chang L, Tang J, Hong X, Zhang Z and Wang H. Some thermodynamic properties of larnite (β-Ca2SiO4) constrained by high T/P experiment and/or theoretical simulation. American Mineralogist (In reviewing; Corresponding Author).
57. 王霏,劉曦,呂明達,張彥垚,張立飛,鄭海飛。一種簡單而有效的防止高溫光譜實驗中顯微物鏡溫度過高的裝置:氣體吹掃裝置。光譜學與光譜分析(評議中;通訊作者)。
56. Liu X, Xiong Z, Chang L, He Q, Wang F, Shieh SR, Wu C, Li B and Zhang L (2015) Anhydrous ringwoodites in the mantle transition zone: their bulk modulus, solid solution behavior, compositional variation, and sound velocity feature. Solid Earth Sciences (In press).
55. 李靜超,趙中寶,鄭藝龍,袁國禮,梁曉,王根厚,劉曦(2015)。古特提斯洋俯沖碰撞在南羌塘的岩漿岩證據:西藏榮瑪鄉岡塘錯花崗岩。岩石學報(出版中)。
54. 陶仁彪,張立飛,劉曦(2015)。地幔氧逸度與俯沖帶深部碳循環。岩石學報(出版中)。
53. 王霏,劉曦,鄭海飛,張立飛(2015)。俯沖帶溫度條件下橄榄石中矽氧四面體的非諧振動:透射紅外光譜研究。岩石學報(出版中;通訊作者)。
52. 呂明達,劉曦,熊志華,王霏(2015)。 高溫高壓實驗中金屬添加物對實驗反應速率的影響:以柯石英-剛玉-藍晶石體系中添加鉑金粉末為例。高壓物理學報29,99-108(通訊作者)。
51. Chang L, Liu X, Wu C, Liu X and Li G (2015). Full and ideal mixing behavior between Zr-Wd (K2ZrSi3O9) and Ti-Wd (K2TiSi3O9): evidences from mineral chemistry, X-ray diffraction pattern and Raman spectrum. Physics and Chemistry of Minerals 42, 223-234 (Corresponding Author).
50. Xiong Z, Liu X, Shieh SR, Wang F, Wu X, Hong X and Shi Y (2015). Equation of state of a synthetic ulvöspinel, (Fe1.94Ti0.03)Ti1.00O4.00, at ambient temperature. Physics and Chemistry of Minerals 42, 171-177 (Corresponding Author).
49. 唐俊傑,劉曦,熊志華,何強,SHIEH R. Sean, 王河錦(2014)。藍柱石的高溫X射線衍射、差熱-熱重分析、偏振紅外光譜和高壓拉曼光譜研究。礦物岩石地球化學通報 33,289-298(通訊作者)。
48. 何強, 唐俊傑, 王霏, 劉曦(2014)。一種适用于極端高溫條件的六面頂壓機實驗組裝。高壓物理學報 28,145-151。
47. Chen Y, Liu X and Zhou Y (2014). 3D-FEM modeling of the microscopic stress field of forsterite aggregate under hydrostatic pressure: significance of the crystal orientation. Science China-Earth Sciences 57, 1192-1198 (Corresponding Author).
46. 劉曦, 常琳琳, 何強(2013)。岩石高溫高壓實驗技術與方法。固體地球科學研究方法 (丁仲禮編),682-698。
45. Chang L, Liu X, Liu H, Kojitani H and Wang S (2013). Vibrational mode analysis and heat capacity calculation of K2SiSi3O9-wadeite. Physics and Chemistry of Minerals 40, 563-574 (Corresponding Author).
44. Deng L, Fei Y, Liu X, Gong Z and Shahar A (2013). Effect of carbon, sulfur and silicon on iron melting at high pressure: implications for composition and evolution of the planetary terrestrial cores. Geochimica et Cosmochimica Acta 114: 220-233.
43. He Q, Liu X, Li B, Deng L, Chen Z, Liu X, and Wang H (2013). Expansivity and compressibility of strontium and barium fluorapatite: Significance of the M-site cations. Physics and Chemistry of Minerals, doi:10.1007/s00269-013-0576-6 (Corresponding Author).
42. Chang L, Chen Z, Liu X and Wang H (2013). Expansivity and compressibility of wadeite-type K2Si4O9 determined by in situ high T/P experiments, and their implication. Physics and Chemistry of Minerals 40, 29-40 (Corresponding Author).
41. Liu X, Ohfuji H, Nishiyama N, He Q, Sanehira T and Irifune T (2012). High-P behavior of anorthite composition and some phase relations of the CaO-Al2O3-SiO2 system to the lower mantle of the Earth, and their geophysical implications. Journal of Geophysical Research-Solid Earth 117, B09205.
40. Liu X, Chen J, Tang J, He Q, Li S, Peng F, He D, Zhang L and Fei Y (2012). A large volume cubic press with a pressure-generating capability up to about 10 GPa. High Pressure Research 40, 239-254.
39. He Q, Liu X, Hu X, Deng L, Chen Z, Li B and Fei Y (2012). Solid solutions between lead fluorapatite and lead fluorvanadate apatite: compressibility determined by using a diamond-anvil cell coupled with synchrotron X-ray diffraction. Physics and Chemistry of Minerals 39, 219-226 (Corresponding Author).
38. Wang S, Liu X, Fei Y, He Q and Wang H (2012). In situ high-temperature powder X-ray diffraction study on the spinel solid solution (Mg1-xMnx)Cr2O4. Physics and Chemistry of Minerals 39, 189-198 (Corresponding Author).
37. Liu X, Wang S, He Q, Chen J, Wang H, Li S, Peng F, Zhang L and Fei Y (2012). Thermal elastic behavior of CaSiO3-walstromite: a powder X-ray diffraction study up to 900oC. American Mineralogist 97, 262-267.
36. He Q, Liu X, Hu X, Li S and Wang H (2011). Solid solution between lead fluorapatite and lead fluorvanadate apatite: mixing behavior, Raman feature and thermal expansivity. Physics and Chemistry of Minerals 38, 741-752 (Corresponding Author).
35. Liu X, He Q, Deng L, Zhai S, Hu X, Li B, Zhang L, Chen Z and Liu Q (2011). Equation of state of CAS phase to pressure of the uppermost lower mantle at ambient temperature. Science China D: Earth Sciences 54, 1394-1399.
34. Deng L, Liu X, Liu H and Zhang Y (2011). A first-principles study of the phase transition from Holl-I to Holl-II in the composition KAlSi3O8. American Mineralogist 96, 974-982 (Corresponding Author).
33. Fleet ME, Liu X and Liu X (2011). Orientation of channel carbonate ions in apatite: effect of pressure and composition. American Mineralogist 96, 1148-1157.
32. Hu X, Liu X, He Q, Wang H, Qin S, Ren L, Wu C and Chang L (2011). Thermal expansion of andalusite and sillimanite at ambient pressure: a powder X-ray diffraction study up to 1000oC. Mineralogical Magazine 75, 363-374 (Corresponding Author).
31. Liu X, Fleet ME, Shieh SR and He Q (2011). Synthetic lead bromapatite: X-ray structure at ambient pressure and compressibility up to about 20 GPa. Physics and Chemistry of Minerals 38, 397-406.
30. Liu X, Liu W, He Q, Deng L, Wang H, He D, Li B (2011). Isotropic thermal expansivity and anisotropic compressibility of ReB2. Chinese Physics Letters 28, 036401.
29. Liu X, Shieh S R, Fleet ME, Zhang L and He Q (2011). Equation of state of carbonated hydroxylapatite at ambient temperature: Significance of carbonate. American Mineralogist 96, 74-80.
28. 劉曦,胡張翼,鄧力維(2010)。長石在高溫高壓條件下的物理化學行為。岩石學報 26,3641-3650。
27. Wang H, He D, Tan N, Wang W, Wang J, Dong H, Ma H, Kou Z, Peng F, Liu X and Li S (2010). Note: an anvil-preformed gasket system to extend pressure range for large volume cubic press. Review of Scientific Instruments 81, 116101.
26. Liu X, He Q, Wang H, Fleet ME and Hu X (2010). Thermal expansion of kyanite at ambient pressure: an X-ray powder diffraction study up to 1000oC. Geoscience Frontiers 1, 91-97.
25. Deng L, Liu X, Liu H and Dong J (2010). High-pressure phase relations in the composition of albite NaAlSi3O8 constrained by an ab initio and quasi-harmonic Debye model, and their implications. Earth and Planetary Science Letters 298, 427-433 (Corresponding Author).
24. Huang T, Shieh SR, Akhmetov A, Liu X, Lin CM, Lee JS (2010). Pressure-induced phase transition in BaCrO4. Physical Review B 81, 214117.
23. Fleet ME and Liu X (2010). X-ray absorption spectroscopy of ultramarine pigments: A new analytical method for the polysulfide radical anion S3- chromophore. Spectrochimica Acta Part B: Atomic Spectroscopy 65, 75-79.
22. Fleet ME, Liu X and Shieh SR (2010). Structural change in lead fluorapatite at high pressure. Physics and Chemistry of Minerals 37, 1-9.
21. 劉曦,張立飛,HACK AC,鄭海飛,胡曉敏,常琳琳,何強(2009)。水對矽酸鹽岩體系部分熔融行為的影響:第二臨界端點的重要意義。岩石學報 25,3407-3421。
20. Zhai S, Liu X, Shieh SR, Zhang L and Ito E (2009). Equation of state of tricalcium phosphate, γ-Ca3(PO4)2, to lower mantle pressures. American Mineralogist 94, 1388-1391 (Corresponding Author).
19. Liu X, Shieh SR, Fleet ME and Zhang L (2009). The compressibility of a natural kyanite at 300 K. Progress in Natural Science 19, 1281-1286.
18. 楊玉萍,鄭海飛,張立飛,劉曦,鄧松濤(2009)。高溫高壓下NaCl-H2O體系的Raman光譜分析:一種新的流體包裹體鹽度測定方法。岩石學報 25,2023-2028。
17. Fleet ME and Liu X (2009). Sodium hydrogen carbonate (NaHCO3): coincidence site lattice twinning and structure refinement. Zeitschrift fur Kristallographie 224, 144-150.
16. Liu X and Fleet ME (2009). Phase relations of nahcolite and trona at moderate P-T conditions. Journal of Mineralogical and Petrological Sciences 104, 25-36.
15. Liu X, Shieh SR, Fleet ME and Akhmetov A (2008). High-pressure study on lead fluorapatite. American Mineralogist 93, 1581-1584.
14. Fleet ME and Liu X (2008). Location of carbonate ions in structure of biological apatite. In: Advances in Bioceramics and Porous Ceramics, Ceramic Engineering and Science Proceedings 29/7 (R Narayan, P Colombo, edits.), Wiley, New York. 63-76.
13. Fleet ME and Liu X (2008). Carbonate in synthetic and biological apatites. Proceedings of Ninth International Congress for Applied Mineralogy (ICAM 2008), 303-311.
12. Fleet ME and Liu X (2008). Type A-B carbonate chlorapatite synthesized at high pressure. Journal of Solid State Chemistry 181, 2494-2500.
11. Fleet ME and Liu X (2008). Accommodation of the carbonate ion in fluoapatite synthesized at high pressure. American Mineralogist 93, 1460-1469.
10. Fleet ME and Liu X (2007). Hydrogen-carbonate ion in synthetic high-pressure apatite. American Mineralogist 92, 1764-1767.
9. Liu X and O’Neill HStC (2007). Effects of P2O5 and TiO2 on the partial melting of spinel lherzolite in the system CaO-MgO-Al2O3-SiO2 at 1.1 GPa. Canadian Mineralogist 45, 649-655.
8. Fleet ME and Liu X (2007). Coupled substitution of type A and B carbonate in sodium-bearing apatite. Biomaterials 28, 916-926.
7. Liu X, Nishiyama N, Sanehira T, Inoue T, Higo Y and Sakamoto S (2006). Decomposition of kyanite and solubility of Al2O3 in stishovite at high pressure and high temperature conditions. Physics and Chemistry of Minerals 33, 711-721.
6. Sueda Y, Irifune T, Yamada A, Inoue T, Liu X and Funakoshi K (2006). The phase boundary between CaSiO3 perovskite and Ca2SiO4 + CaSi2O5 determined by in situ X-ray observations. Geophysical Research Letters 33, L10307.
5. Liu X (2006). Phase relations in the system KAlSi3O8-NaAlSi3O8 at high pressure-high temperature conditions and their implication for the petrogenesis of lingunite. Earth and Planetary Science Letters 246, 317-325.
4. Liu X, O’Neill HStC and Berry AJ (2006). Partial melting of spinel lherzolite in the system CaO-MgO-Al2O3-SiO2-H2O-CO2-Na2O at 1.1 GPa. Journal of Petrology 47, 409-434.
3. Liu X and O’Neill HStC (2004). The effect of Cr2O3 on the partial melting of spinel lherzolite in the system CaO-MgO-Al2O3-SiO2-Cr2O3 at 1.1 GPa. Journal of Petrology 45, 2261-2286.
2. Liu X and O’Neill HStC (2004). Partial melting of spinel lherzolite in the system CaO-MgO-Al2O3-SiO2±K2O at 1.1 GPa. Journal of Petrology 45, 1339-1368.
1. Liu X and Wang QC (1998). Quartz-ecolgite in Shuanghe Area of the Dabie Mountains: hot or cold? Scientia Geologica Sinica 7, 569-575.