Prof. Dr. Huaiwei Ni
(As of Jun 1, 2014)
Born at Suzhou, Anhui in Nov 1981
1997-2002: SESS, USTC, Bachelor in Geochemistry
2003-2008: The University of Michigan, Ph.D. in Geology (conferred in May 2009)
2009-2012: Bayerisches Geoinstitut, Universität Bayreuth, Postdoctoral scholar
Feb 2012: Enrolled in National “Recruitment Program of Global Experts (Junior)”
May 2012: SESS, USTC, Professor
2013: Sponsored by NSFC Excellent Young Investigator Grant
Experimental petrology, Computational geochemistry, Geochemical kinetics
Chinese Society for Mineralogy Petrology and Geochemistry, American Geophysical Union, Geochemical Society, Mineralogical Society of America
Research interests and performance
High-temperature high-pressure experiments
First-principles molecular dynamics
Physicochemical properties of silicate melts and hydrothermal fluids
Partial melting in the Earth and other terrestrial planet
The formation and evolution of Earth’s mantle and crust
1. Develop the methodology of in situ measuring electrical conductivity of volatile-bearing silicate melts under high temperature and high pressure (corresponding to the upper mantle conditions) in piston-cylinder and multianvil presses. Approximately 1 vol% hydrous basaltic melt segregated in tube-like structures along the direction of plate spreading is able to account for the conductivity anomaly and anisotropy observed in the asthenospheric low-velocity zone.
2. Construct universal models for water diffusivity in silicate melts by quantifying the effects of temperature, pressure and melt H2O in rhyolitic, dacitic and andesitic melts, which provides one of the most important parameters in modeling and understanding bubble growth and general dynamics of gas-driven volcanic eruptions. Create the concept of “pseudoalkali” to elucidate the complex effects of ion size on diffusion and the relation between alkali diffusivity and melt composition.
3. From first-time in situ microscopic observation of the crystallization processes of olivine, clinopyroxene, and plagioclase from basaltic melt in a moissanite cell, find that nucleation usually occurs within a short time and temperature interval, and crystal growth rate is roughly proportional to crystal size. The practice of inferring crystal growth rate and nucleation rate based on the classical Crystal Size Distribution theory may be in error.
4. Derive the structure and properties of alkali-bearing silicate melts under mantle conditions using first-principles molecular dynamics, and find that several characteristics of Na+ as network-modifiers are consistently diminishing with the increase of pressure. The limited Na+ mobility suggests that electrical conductivity of plausible melts at the core-mantle boundary may be lower than previously expected and such melts if present are difficult to identify using magnetotelluric survey.
Guo, Xuan (Postdoctoral Scholar) and Wei, Longmeng (Master student): Electrical conductivity of silicate melts; Element partitioning between minerals and silicate melts
Zhang, Li (Master student): Diffusivity in silicate melts
Chen, Qi (Master student) and Pan, Yun (Undergraduate student): Electrical conductivity of aqueous fluids
Yang, Kai (Master student) and Li, Zhenjiang (Undergraduate student): Sulfur speciation and partitioning in silicate melts and fluids
*Ni H.W., Keppler H., Walte N., Schiavi F., Chen Y., Masotta M., Li Z. (2014) In situ observation of crystal growth in a basalt melt and the development of crystal size distribution in igneous rocks. Contributions to Mineralogy and Petrology, 167, 1003, doi:10.1007/s00410-014-1003-9
*Ni H.W. (2014) The relationship between apparent equilibrium temperature and closure temperature with application to oxygen isotope geospeedometry. Chinese Journal of Geochemistry, 33, 125-130.
Masotta M., Ni H. W., Keppler H. (2014) In situ observations of bubble growth in basaltic, andesitic and rhyodacitic melts. Contributions to Mineralogy and Petrology, 167, 976, doi:10.1007/s00410-014-0976-8
*Ni H.W., de Koker N. (2014) Diffusion in oxide glass-forming systems. In Encyclopedia of Glasses, Richet P. (ed), Wiley, in press.
*Ni H.W., Xu Z., Zhang Y. (2013) Hydroxyl and molecular H2O diffusivity in a haploandesitic melt. Geochimica et Cosmochimica Acta, 103, 36-48.
Ni H.W., *Keppler H. (2013) Carbon in silicate melts. Review in Mineralogy and Geochemistry, 75, 251-287.
倪怀玮 (2013) 硅酸盐熔体的物理化学性质研究进展及其应用. 科学通报, 58, 865-890.
Ni H.W., Keppler H. (2012) In situ Raman spectroscopy on sulfur speciation in oxidized magmatic-hydrothermal fluids. American Mineralogist, 97, doi:10.2138/am.2012.4003
Ni H.W. (2012) Compositional dependence of alkali diffusivity in silicate melts: mixed alkali effect and pseudo alkali effect. American Mineralogist, 97, 70-79.
Yang X.-Z., Keppler H., McCammon C., Ni H.W. (2012) Electrical conductivity of orthopyroxene and plagioclase in the lower crust. Contributions to Mineralogy and Petrology, 163, 33-48.
Ni H.W., de Koker N. (2011) Thermodynamics, diffusion and structure of NaAlSi2O6 liquid at mantle conditions: a first-principles molecular dynamics investigation. Journal of Geophysical Research, 116, B09202, doi:10.1029/2010JB008072
Ni H.W., Keppler H., Manthilake M.A.G.M., Katsura T. (2011a) Electrical conductivity of dry and hydrous NaAlSi3O8 glasses and liquids at high pressures. Contributions to Mineralogy and Petrology, 162, 501-513.
Ni H.W., Keppler H., Behrens H. (2011b) Electrical conductivity of hydrous basaltic melts: implications for partial melting in the upper mantle. Contributions to Mineralogy and Petrology, 162, 637-650.
Xiong X.L., Keppler H., Audétat A., Ni H.W., Sun W., Li Y. (2011) Partitioning of Nb and Ta between rutile and felsic melt and the fractionation of Nb/Ta during partial melting of hydrous metabasalt. Geochimica et Cosmochimica Acta, 75, 1673-1692.
Yang X.-Z., Keppler H., McCammon C., Ni H.W., Xia Q.-K., Fan Q.-C. (2011) The effect of water on the electrical conductivity of lower crustal clinopyroxene. Journal of Geophysical Research, 116, B04208, doi:10.1029/2010JB008010
Zhang Y., Ni H.W. (2010) Diffusion of H, C, and O components in silicate melts. Review in Mineralogy and Geochemistry, 72, 171-225.
Zhang Y., Ni H.W., Chen Y. (2010) Diffusion data in silicate melts. Review in Mineralogy and Geochemistry, 72, 311-408.
Ni H.W., Liu Y., Wang L.J., Zhang Y. (2009a) Water speciation and diffusion in haploandesitic melts at 743-873 K and 100 MPa. Geochimica et Cosmochimica Acta, 73, 3630-3641.
Ni H.W., Behrens H., Zhang Y. (2009b) Water diffusion in dacitic melt. Geochimica et Cosmochimica Acta, 73, 3642-3655.
Ni H.W., Zhang Y. (2008) H2O diffusion models in rhyolitic melt with new high pressure data. Chemical Geology, 250, 68-78.