Webster, James main content.

James Webster

A man, James Webster, on small boat wearing a windbreaker and life preserver jacket. Water and hills in background.

Curator Emeritus, Department of Earth and Planetary Sciences, Division of Physical Sciences
Professor Emeritus, Richard Gilder Graduate School

In Memoriam


  • Arizona State University, Ph.D, 1987
  • Colorado School of Mines, M.S., 1980
  • North Carolina State University, B.S., 1978

Research Interests

Dr. Webster investigates how the volatiles water, fluorine, chlorine, sulfur, and carbon dioxide influence how magmas evolve chemically; how they control the formation of metallic ore deposits; and how they impact volcanic eruptions. He investigates how ore deposits are generated through late-stage hydrothermal and mineralizing processes in magmas.  Dr. Webster also studies the influence of volatiles on the melting behavior and stability of minerals, and how and when magmatic-hydrothermal fluids are released from magma. This research involves study of silicate melt inclusions, which are microscopic inclusions of silicate melt trapped in minerals from mineralizing and/or erupting magmas. To assist in this research, he has recently constructed a Vernadsky-style heating stage for observing silicate melt inclusions, with a microscope, while they are melted at high temperatures.  He is presently working on hydrothermal experiments involving apatite, silicate melts, and volatile-rich fluids to better understand magmatic processes. With scientists from the University of Hannover, Germany, he is developing a model to compute Cl solubilities in silicate melts.  Other research – with museum colleagues – on sulfur, chlorine, carbon dioxide, and water provides information on the nature of gases released during explosive volcanism at Augustine volcano, Alaska, and Dr. Webster has recently begun a new study on sapphire- and spinel-bearing metamorphic rocks of the Mogok region of Myanmar. 


  • Goldoff, B., Webster, J.D., Harlov, D. (2012) Characterization of fluor-chlorapatites by electron probe microanalysis with a focus on time-dependent intensity variation of halogens.  American Mineralogist 97, 1103-1115.
  • Webster, J.D., Botcharnikov, R.E. (2011) Distribution of sulfur between melt and fluid in S-O-H-C-Cl-bearing magmatic systems at shallow crustal pressures and temperatures. In: H. Behrens and J.D. Webster, eds., Sulfur in Magmas and Melts and its Importance for Natural and Technical Processes, Reviews in Mineralogy and Geochemistry 74, 247-283.
  • Di Martino, C., Forni, F., Frezzotti, M.L., Palmeri, R., Webster, J.D., Ayuso, R., Lucchi, F., Tranne, C.A. (2010) Formation of cordierite-bearing lavas during anatexis in the lower crust of Lipari (Aeolian Islands, Italy). Contributions to Mineralogy and Petrology, DOI:http://www.springerlink.com/content/0010- 7999/?k=beryllium&Article+Category=Original+Paper&o=10.
  • Thomas, R., Webster, J.D., and Davidson, P. (2010) Be daughter minerals in fluid and melt inclusions – Implications for the enrichment of Be in granite-pegmatite systems. Contributions to Mineralogy and Petrology 161, 483-495.
  • Webster, J.D., Mandeville, C.W., Goldoff, B., Coombs, M.L., Tappen, C. (2010) Augustine volcano, Alaska: The influence of volatile components in magmas erupted AD 2006 to 2100 years before present.  In: J. Power, M.L. Coombs, J. Freymueller, eds., The 2006 Eruption of Augustine Volcano, U.S. Geol. Surv. Prof. Paper 1769, 383-423.

Teaching Experience

Faculty Appointments

  • Co-PI and Co-Manager of AMNH Physical Sciences REU Program
  • AMNH Masters of Arts in Teaching Program

Courses Taught

  • Fluids in the Earth, University of Naples, Italy

Graduate Advisees

  • Alexander Iveson, Washington State University-Pullman
  • Angela Doherty, University of Messina, Italy

Graduate Committees

  • Alexander Lloyd, LDEO, Columbia University