Prof. Robin, The article by Stephen Mackwell, "Melt inclusions in olivine: Reliable witnesses to Earth’s interior?" Geology, vol 40, pp 959 , 2012.will be of Great use. The other reprint which my be of some use is from Chemical Geology, 2007

http://www.people.fas.harvard.edu/~laubier/ChemGeol2007.pdf

The following treatment holds if you have a spherical shape and a void contraction bubble, otherwise you need to handle formulas providing volume measurements and equation of state of the phase(s) contained in the contraction bubble.

If you have a melt inclusion of spherical shape the with a contraction bubble, the conservation of mass provides ...

see attached file for formulas

I have a code that handles rapidly all the model, if you want share your data I would be glad to share the model in order to write a paper.

Best regards

Dear Robin,

There are several papers reviewing and discussing the significance of melt inclusions starting back in 1858 with the Sorby’s paper. However, I would like to suggest you starting with Roedder (1979) that is a very clear introduction to melt inclusion. You can find and download this publication at the Bodnar’s Lab of VT webpage (http://www.geochem.geos.vt.edu/fluids/) click on Edwin Roedder memorial virtual library on the right. The Russian literature on significance of melt inclusions is wide and important, but hard to find (see Sobolev, A.V., and Kostyuk, V.P. (1976) Magmatic crystallization based on study of melt inclusions. Fluid inclusion research, 9, 182-253.). Other good contributions to start understanding the melt inclusion technique are:

Lowenstern, J.B. (1995) Applications of silicate-melt inclusions to the study of magmatic volatiles. Short Course Handbook, 23, 71-99.

Audétat, A., and Lowenstern, J.B. (2014) 13.6 - Melt Inclusions. In H.D. Holland, and K.K. Turekian, Eds. Treatise on Geochemistry (Second Edition), p. 143-173. Elsevier, Oxford.

Frezzotti, M.-L. (2001) Silicate-melt inclusions in magmatic rocks: applications to petrology. Lithos, 55(1–4), 273-299.

Métrich, N., and Wallace, P.J. (2008) Volatile abundances in basaltic magmas and their degassing paths tracked by melt inclusions. In K.D. Putirka, and F.J. Tepley, III, Eds. MInerals, Inclusions and Volcanic Processes, 69, p. 363-402. The Mineralogical Society of America.

Kent, A.J.R. (2008) Melt inclusions in basaltic and related volcanic rocks. In K.D. Putirka, and F.J. Tepley, III, Eds. MInerals, Inclusions and Volcanic Processes, 69, p. 273-331. The Mineralogical Society of America.

Schiano, P. (2003) Primitive mantle magmas recorded as silicate melt inclusions in igneous minerals. Earth-Science Reviews, 63(1-2), 121-144.

Sobolev, A.V. (1996) Melt inclusions in minerals as a source of principal petrological information. Petrology, 4(3), 209-220.

Bodnar, R.J., and Student, J.J. (2006) Melt inclusions in plutonic rocks: Petrography and microthermometry. Melt Inclusions in Plutonic Rocks, 36(Short Course ), 1-25.

De Vivo, B., and Bodnar, R.J. (2003) Melt inclusions in volcanic systems. Elsevier Sciences, Amsterdam.

And others…

Regarding what you can do with the volume of melt inclusion (MI), the proposed calculation by Armienti is very interesting and smart.

Based on your X-ray tomography technique, you can obtain one of the most important petrographic information regarding MI. That is the ratio between the total volume of MI and the volume of the bubble. If this ratio is constant in most of the MI from olivines of one single volcanic sample, then you can assess that all the bubbles of the MI studied have originated as “shrinkage” bubbles (see Roedder 1979 for better explanation). If the ratio is highly variable, it is likely possible that the melt was saturated during olivine crystallization and that you have heterogeneously trapped melt plus fluid.

I strongly believe that is difficult to find a void bubble in a MI unless the trapped melt was volatile-poor, and melts from Etna are known to be volatile-rich (Metrich and Wallace and references therein). Rather, the shrinkage bubble has undetectable amount of gas or vapor reacted with glass at the interface (Roedder, 1979). Al though is not easy task to understand the evolution of MI after trapping (Steele-MacInnis et al., 2011 and reference therein), as a shrinkage bubble forms the internal pressure of the MI should decrease and melt of the MI should exsolve volatiles in the bubble. There is a lot of debate on modification of MI after trapping.

Also, I recommend you to understand the meaning of the temperature of homogenization that is needed in Armienti’s calculation. There are things you need to be aware about this parameter, and I would suggest reading these two papers:

“Danyushevsky, L.V., McNeill, A.W., and Sobolev, A.V. (2002) Experimental and petrological studies of melt inclusions in phenocrysts from mantle-derived magmas: an overview of techniques, advantages and complications. Chemical Geology, 183(1-4), 5-24.

Esposito, R., Klebesz, R., Bartoli, O., Klyukin, Y.I., Moncada, D., Doherty, A.L., and Bodnar, R.J. (2012) Application of the Linkam TS1400XY heating stage to melt inclusion studies. Central European Journal of Geosciences, 4(2), 208-218.”

Also, I would like to let you notice that in Steele-MacInnis et al. (2011, Table 1 and Fig. 3) and Esposito et al. (2011, Table 5) we have done a mass balance calculation of the total CO2 of an MI (CO2 dissolved in the glass plus CO2 in vapor-bubble), and the use of your technique could have greatly improved the precision of the calculation. Please, read the text for more details or contact me if you would like to have additional information about this.

If you would like, I am opened and available for future contributions or suggestions.

Hope this helps and sorry if I have been too wordy

Rosario

Steele-MacInnis, M.J., Esposito, R., and Bodnar, R.J. (2011) Thermodynamic model for the effect of post-entrapment crystallization on the H2O-CO2 systematics of volatile saturated silicate melt inclusions. . Journal of Petrology, 52(12), 2461-2482.

Esposito, R., Bodnar, R.J., Danyushevsky, L., De Vivo, B., Fedele, L., Hunter, J., Lima, A., and Shimizu, N. (2011) Volatile Evolution of Magma Associated with the Solchiaro Eruption in the Phlegrean Volcanic District (Italy). Journal of Petrology, 52(12), 2431-2460.

Dear Robin,

It might be useful to find a larger thin section and see if other grains contain the same inclusion and if there is an orientation. If there is this gives information about flow with in the magma. Of course the chemistry of the inclusions compared to the host rock may give information of physical location at time of formation and previous. Such inclusions are always important for evaluating the chemistry of the magma chamber which relates to valatility, etc.

Dear Jeffrey,

Could you please provide a reference for your statement:

It might be useful to find a larger thin section and see if other grains contain the same inclusion and if there is an orientation. "If there is this gives information about flow with in the magma"

In my opinion, information about flow within the magma based on melt inclusions sounds awkward.

Rosario

This comes from conversations with other colleagues. My wording is not always the best.

Dear Robin,

This last AGU, I stopped by a poster presentation and I was glad to talk to Glen Gaetani about the work he presented. As I was suggesting to you more than a year ago, they used X-ray micro-tomography to study bubbles in melt inclusions hosted in olivine.

V13B-3124: Reconstructing magma storage depths from olivine-hosted melt inclusions: Do vapor bubbles matter? (Gaetani et al.)

Happy holidays,

Rosario