pygcc.clay_thermocalc

Created on Wed Mar 17 16:02:22 2021

@author: Adedapo Awolayo and Ben Tutolo, University of Calgary

Copyright (c) 2020 - 2021, Adedapo Awolayo and Ben Tutolo, University of Calgary

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>.

Module Contents

Functions

roundup_tenth(x)

Molecularweight()

This function stores the Molecular weight of all elements

calclogKclays(TC, P, *elem[, dbaccessdic, group, ...])

This function calculates logK values and reaction parameters of clay reactions using below references:

Attributes

MW

J_to_cal

pygcc.clay_thermocalc.roundup_tenth(x)[source]
pygcc.clay_thermocalc.Molecularweight()[source]

This function stores the Molecular weight of all elements

pygcc.clay_thermocalc.MW
pygcc.clay_thermocalc.J_to_cal = 4.184
pygcc.clay_thermocalc.calclogKclays(TC, P, *elem, dbaccessdic=None, group=None, cation_order=None, Dielec_method=None, ClayMintype=None, ThermoInUnit='cal', **rhoEG)[source]

This function calculates logK values and reaction parameters of clay reactions using below references:

Parameters:

  • TC (float, vector) – Temperature [°C]

  • P (float, vector) – Pressure [bar]

  • elem (list) – list containing nine parameters with clay names and elements compositions with the following format [‘Montmorillonite_Lc_MgK’, ‘Si’, ‘Al’, ‘FeIII’, ‘FeII’, ‘Mg’, ‘K’, ‘Na’, ‘Ca’, ‘Li’]

  • dbacessdic (dict) – dictionary of species from direct-access database, optional, default is speq21

  • group (string) – specify the structural layering of the phyllosilicate, for layers composed of 1 tetrahedral + 1 octahedral sheet (1:1 layer) - specify ‘7A’, 2 tetrahedral + 1 octahedral sheet (2:1 layer) - specify ‘10A’, or the latter with a brucitic sheet in the interlayer (2:1:1 layer) - specify ‘14A’ (optional), if not specified, default is based on charge balance on the cations and anions

  • cation_order (string) – specify ordering of Si and Al ions either ‘Eastonite’, ‘Ordered’, ‘Random’, or ‘HDC’ (optional), if not specified, default is based on guidelines by Vinograd (1995)

  • Dielec_method (string) – specify either ‘FGL97’ or ‘JN91’ or ‘DEW’ as the method to calculate dielectric constant (optional), if not specified, default - ‘JN91’

  • ClayMintype (string) – specify either ‘Smectite’ or ‘Chlorite’ or ‘Mica’ as the clay type, if not specified default - ‘Smectites’

  • ThermoInUnit (string) – specify either ‘cal’ or ‘KJ’ as the input units for species properties (optional), particularly used to covert KJ data to cal by supcrtaq function if not specified default - ‘cal’

  • rhoEG (dict) – dictionary of water properties like density (rho), dielectric factor (E) and Gibbs Energy (optional)

Returns:

  • logK_clay (float, vector) – logarithmic K values

  • Rxn (dict) – dictionary of reaction thermodynamic properties

Usage

The general usage of calclogKclays is as follows:

  1. Without the optional arguments, not on steam saturation curve:

    [logK, Rxn] = calclogKclays(TC, P, *elem),

    where T is temperature in celsius and P is pressure in bar;

  2. Without the optional arguments, on steam saturation curve:

    [logK, Rxn] = calclogKclays(TC, ‘T’, *elem),

    where T is temperature in celsius, followed with a quoted char ‘T’

    [logK, Rxn] = calclogKclays(P, ‘P’, *elem),

    where P is pressure in bar, followed with a quoted char ‘P’.

  3. Meanwhile, usage with any specific dielectric constant method (‘FGL97’) for condition not on steam saturation curve is as follows. Default method is ‘JN91’

    [logK, Rxn] = calclogKclays(TC, P, *elem, dbacessdic = dbacessdic, group = ‘10A’, cation_order = ‘HDC’, Dielec_method = ‘FGL97’)

Examples

>>> logK, Rxn = calclogKclays(50, 'T', *['Clinochlore', '3', '2', '0', '0',
                                         '5', '0', '0', '0', '0'],
                              group = '14A')
>>> logK
    57.56820225

References

  1. Blanc, P., Vieillard, P., Gailhanou, H., Gaboreau, S., Gaucher, É., Fialips, C. I., Madé, B & Giffaut, E. (2015). A generalized model for predicting the thermodynamic properties of clay minerals. American journal of science, 315(8), 734-780.

  2. Blanc, P., Gherardi, F., Vieillard, P., Marty, N. C. M., Gailhanou, H., Gaboreau, S., Letat, B., Geloni, C., Gaucher, E.C. and Madé, B. (2021). Thermodynamics for clay minerals: calculation tools and application to the case of illite/smectite interstratified minerals. Applied Geochemistry, 104986.

  3. Vinograd, V.L., 1995. Substitution of [4]Al in layer silicates: Calculation of the Al-Si configurational entropy according to 29Si NMR Spectra. Physics and Chemistry of Minerals 22, 87-98.