John,
Ed Poindexter has retired to Ann Arbor and is a great supporter
of the Department.
cheers,
eric
On Apr 8, 2008, at 6:29 PM, John Rosenfeld wrote:
> John,
> In your catalogue of references you list separately from the
> various geochemical thermobarometers the heading,
> "piezothermometry." Thermobarometry is synonymous with
> piezothermometry. "Piezo" is derived from the Greek word, "piezein"
> standing for "press." What you have listed as piezothermometry
> should be called solid inclusion piezothermometry or solid
> inclusion thermobarometry. Geochemical thermobarometers are based
> on the chemical properties of minerals and mineral combinations to
> the exclusion of other ways of getting thermobarometric information
> on metamorphic rocks. But what the work that we at UCLA and UC
> Riverside and others in the United Kingdom did was to show that
> there is another way of getting the same information based on
> physical properties of minerals and their inclusions, namely
> thermal expansivities and compressibilities and their responses in
> the form of piezobirefringent [a term that I recall was coined by
> Ed Poindexter, then at the University of Michigan, referring to
> birefringence caused by non-hydrostatic stress] haloes in encasing
> minerals and lattice spacings of encased minerals (cf. the work of
> J.W. Harris et al., 1970). Thus we called this new method solid
> inclusion piezothermometry. However the term, thermobarometry,
> seems to have won general acceptance. To my knowledge the word,
> thermobarometry, did not exist at the time we coined the term
> "piezothermometry." But to be aware of some of the older work,
> metamorphic petrologists should be aware of the synonymy. At the
> time I had an old Webster that defined "piezometer" as a device to
> measure pressure and had also observed that Willard Gibbs in his
> first paper on the thermodynamics of fluids had defined what are
> now called isobars (after the specialized usage of meteorologists
> for contours of constant atmospheric pressure) as isopiestic curves
> (Gibbs, 1873, Trans. Conn. Academy, p. 309-342). Some modern
> dictionaries restrict piezometers to devices for measuring fluid
> pressure, but I doubt that Gibbs would have been so restrictive.
> The modern on-line Merriam-Webster returns to piezometer as the
> general term for a device to measure pressure:
>
> http://medical.merriam-webster.com/medical/piezometer
> http://medical.merriam-webster.com/medical/thermometer
> Separately, I will send you a few references, some of which you may
> want to add to your selected bibliography on solid inclusion
> thermobarometry. There is now a considerable literature on the
> subject.
>
> I think what you are providing is a valuable contribution to
> metamorphic petrology.
>
> Best regards,
>
> John Rosenfeld
> <http://www.ess.ucla.edu/faculty/rosenfeld/index.asp>
