Practical Aspects of Mineral Thermobarometry http://www.earth.ox.ac.uk/~davewa/pt/pt-start.html
University of OxfordのDepartment of Earth SciencesのDave
Waters氏による。
『These pages provide information, tutorial material
and worked examples for petrology students interested in extracting
pressure-temperature information from rocks. It is assumed that
you have completed a typical undergraduate petrology course.
The sequence of topics, listed below, progresses from the acquisition
of mineral analyses to computer-based P-T and phase diagram calculations.
The content of these pages gets updated periodically but irregularly.
The current edition was prompted by the availability of version
3 of the THERMOCALC software for Mac and PC, and the old documentation
is being brought into line with the capabilities of this release.
Some material previously restricted to the Oxford domain has
been moved to these public pages. The site redesign should make
it easier to find things. Text-book
The theoretical content is not self-contained - you will need
to refer to other texts and papers. The most useful text is Frank
Spear's Metamorphic Phase Equilibria and Pressure-Temperature-Time
Paths (1993, Mineralogical Society of America), and many of the
sections below refer you directly to the appropriate part of
this book. If you want to buy this book, it's probably worth
ordering direct
from the MSA rather than going through a bookstore. Thermodynamic calculation software
The P-T calculation method used involves Roger Powell and Tim
Holland's program THERMOCALC with its associated thermodynamic
data set, described in a number of papers, the most recent at
the time of writing being Holland and Powell (1998), Journal
of Metamorphic Geology 16, 309-343, and Powell et al.(1998),
Journal of Metamorphic Geology 16, 577-588. See the bibliography
for more detail.』
１）Microprobe
analyses
２）Chemical
mineralogy of common mineral groups
３）Solid
solutions, mixing models and activity calculations
４）Thermobarometer
calibrations
５）Error
estimation in P-T calculations
６）Use
of THERMOCALC for P-T calculations
７）Use
of THERMOCALC in phase-diagram mode
８）THERMOCALC
tips and examples
THERMOBAROMETRY（Garnet - Cordierite - Spinel
- Sillimanite/Kyanite - Quartz） http://www.es.mq.edu.au/geology/geoff/geotherm/html/
『This programme calculates pressures and temperatures
for garnet - cordierite - spinel - sillimanite/kyanite - quartz
anhydrous or hydrous pelitic assemblages. It is derived from
the shareware NICHOLS programme, which is available in either
Macintosh or PC friendly formats. This version additionally allows
the P vs T graphical representation of the calculated isopleths.
Experimental and thermodynamic data as well as the derived temperature
and pressure equations are published in Nichols, G.T., Berry, R.F. and Green, D.H. 1992. Internally
consistent gahnitic spinel-cordierite-garnet equilibria in the
FMASHZn system: geothermobarometry and applications. Contributions
to Mineralogy and Petrology, 111:362-377. Before starting thermobarometry, please note that mineral-cation
data will be required. Cations are assumed to be calculated on
the basis of 12 O for garnet, 18 O for cordierite, and 4 O for
spinel.』
【相図】
相図 http://ja.wikipedia.org/wiki/%E7%9B%B8%E5%9B%B3
『相図（そうず、phase diagram）は物質や系（モデルなどの仮想的なものも含む）の相と熱力学的な状態量との関係を表したもの。
状態図とも呼ばれる。例として、合金や化合物の温度や圧力に関しての相図、モデル計算によって得られた系の磁気構造と温度との関係（これ以外の関係の場合もある）を示す相図などがある。（以下略）』 Phase diagram http://en.wikipedia.org/wiki/Phase_diagram
ギブズの相律 http://ja.wikipedia.org/wiki/%E3%82%AE%E3%83%96%E3%82%BA%E3%81%AE%E7%9B%B8%E5%BE%8B
『ギブズの相律（-そうりつ）は系の自由度を規定する式で、相と成分で次のように規定される。ギブズが発見した式で、単に「相律」ともいう。
F=C-P+2
Fは自由度、Cは成分の数、Pは相の数をいう。
相律の式の中の定数“2”は、温度Tと圧力Pの二つの示強性の変数から来ている。（以下略）』 Gibbs' phase rule http://en.wikipedia.org/wiki/Gibbs%27_phase_rule
『The phase rule of Willard Josiah Gibbs in the
1870 is the fundamental rule which phase diagrams are based on.
P + F = C + 2
P is the number of phases present in equilibrium (Types of solid,
liquid, gas phases etc). F is the number of degrees of freedom
or independent variables taken from temperature, pressure and
composition of the phases present. C is the number of chemical
components required to describe the system.（以下略）』