1-20 OF 43 RESULTS FOR

UNITHERM

Results shown limited to content with bounding coordinates.
Follow your search
Access your saved searches in your account

Would you like to receive an alert when new items match your search?
Close Modal
Sort by
Journal Article
Journal: Economic Geology
Published: 01 September 2004
Economic Geology (2004) 99 (6): 1145–1176.
... from these conditions down to 400°C and 200 MPa, using the Gibbs minimization method with HCh software and the UNITHERM database. Both simple fluid-rock mixing models and more complicated reactor-style algorithms used a range of input fluids (from fluids equilibrated fluid with two-feldspar granite...
FIGURES | View All (19)
Image
Plots of the solubility of Au as calaverite (A) and Ag as hessite (B) as a ...
Published: 01 September 2018
reflect sulfidation, whereas path 2 could reflect the condensation of a H 2 Te vapor, and path 3 a combination of the two processes. The diagrams were constructed using the program Unitherm ( Shvarov, 2011 ) with some of the thermodynamic data by Mills (1974) , Afifi et al. (1988) , McPhail (1995
Image
Stability relationships of selected skarn mineral assemblages as a function...
Published: 01 December 2010
for reactions involving andradite (Ad 90 ) and correspond to those of the solid lines labeled G1 to G4, involving grandite (Ad 55 ). Equilibrium reaction boundaries were calculated using UNITHERM ( Shvarov and Bastrakov, 1999 ) and thermodynamic data for the minerals and CO 2 from Holland and Powell (1998
Image
(A) Hydrothermal stability of relevant iron silicates and iron oxides as a ...
Published: 01 December 2017
between biotite (annite), magnetite, and ankerite (the observed mineral assemblage in the Basal zone). All reactions are listed in Table 9 . We used the thermodynamic data of Holland and Powell (1998) and the program Unitherm ( Shvarov, 2011 ) to calculate the equilibria. Abbreviations: Kfs = K
Image
( a ) Positions of equilibria 6 and 10 in  T - a  SiO 2   space for unit ac...
Published: 01 January 2011
= 0.8 and a Ab = 0.8. Silica activities from equilibrium 6 were calculated with Unitherm, and the AUNIlF surfaces were calculated with the QUIlF program. reference reactions of QUIlF and AUNIlF are bold; all reaction curves were calculated at P = 1 bar.
Image
Activity-activity diagrams showing stability fields for skarn minerals as a...
Published: 01 December 2010
(Ad 90 ), An = anorthite, Cc = calcite, Cz = Clinozoisite (Cz), Gd = grandite (Ad 55 ), Hd = hedenergite (Hd 70 ), Ma = margarite, Mt = magnetite, Qz = quartz, Wo = wollastonite. Equilibrium reaction boundaries were calculated using UNITHERM ( Shvarov and Bastrakov, 1999 ) and thermodynamic data
Journal Article
Published: 01 May 2011
Russ. Geol. Geophys. (2011) 52 (5): 548–554.
.... The latter five minerals are either occasional or are present in particular depth ranges. The calculations were made for the multicomponent system H–O–C–Al–Si–Cl–S–Na–K–Ca–Mg–Fe at 25 ºC and 1 atm, using the HCh (HydroChemistry) software and its UNITHERM databank ( Shvarov, 1999 ). This databank...
FIGURES
Journal Article
Journal: Economic Geology
Published: 01 December 2008
Economic Geology (2008) 103 (8): 1613–1640.
... UNITHERM database for the HCh package for geochemical modelling: unpublished computer file Graphite Shvarov, Yu.V., Borisov, M.V., Grichuk, D.V., and Bastrakov, E.N., 1999, Default UNITHERM database for the HCh package for geochemical modelling: unpublished computer file Quartz Helgeson et al...
FIGURES | View All (10)
Image
F ig . 14. Na-K activity-activity diagram, constructed for the P-T conditio...
Published: 01 September 2004
F ig . 14. Na-K activity-activity diagram, constructed for the P-T conditions indicated using the ACT2 module of The Geochemists Workbench (version 4.0.2, Bethke, 2002 ) and a revised thermodynamic dataset derived from the UNITHERM database of HCh, using the UT2K and K2GWB utilities of Cleverley
Journal Article
Journal: Economic Geology
Published: 01 May 2020
Economic Geology (2020) 115 (3): 661–669.
... –1,194.19 ± 0.25 –832.427 –278.199 –691.025 –258.078 300 –901.20 ± 0.24 –1,205.88 ± 0.17 –823.771 –282.229 –697.294 –263.856 350 –908.96 ± 0.32 –1,225.27 ± 0.17 –805.363 –286.101 –703.857 –269.957 1 This study, determined using the program OptimA 2 The Unitherm database...
FIGURES | View All (13)
Image
F ig . 16. Reactor-type HCh models portraying progressive infiltration of t...
Published: 01 September 2004
. Models (b), (d), and (f) show isothermal infiltration of calc-silicate rocks with the same three fluids. The real starting rocks contain scapolite, but our version of UNITHERM contained no scapolite data. However, the predicted plagioclase composition (An 60 ) is similar to the equivalent anorthite
Journal Article
Journal: Economic Geology
Published: 01 June 2006
Economic Geology (2006) 101 (4): 805–817.
... the assemblage that has the lowest free energy for the specified pressure, temperature, and system composition. However, the Unitherm database that accompanies HCh is not internally consistent (see the Appendix or data sources) which increases the uncertainties on calculated results. Further, HCh lacks...
FIGURES | View All (7)
Journal Article
Published: 01 October 2017
Russ. Geol. Geophys. (2017) 58 (10): 1199–1210.
... energy) and containing the UNITHERM thermodynamic-potential databank ( Shvarov, 2008 ). The databank was supplemented with the consistent values of the free energy of formation of evaporite minerals. The mineral saturation indices (SI) of brines were calculated as the ratios of the ion activity products...
FIGURES | View All (6)
Journal Article
Published: 01 June 2016
American Mineralogist (2016) 101 (6): 1431–1437.
.... U.S . Geological Survey Bulletin , 2131 , 461 p. Shvarov Y.V. ( 2015 ) A suite of programs, OptimA, OptimB, OptimC, and OptimS compatible with the Unitherm database, for deriving the thermodynamic properties of aqueous species from solubility, potentiometry and spectroscopy measurements...
FIGURES
Journal Article
Published: 01 June 2015
Russ. Geol. Geophys. (2015) 56 (6): 893–902.
..., and barite at given PT conditions. Computer calculations were performed using the HCh software based on the UNITHERM thermodynamic data ( Shvarov, 2008 ). In addition, calculations were conducted taking into account the nonideal sphalerite composition using the specially developed module “ZnS_FeS” ( Laptev...
FIGURES | View All (6)
Journal Article
Published: 01 January 2011
American Mineralogist (2011) 96 (1): 100–110.
... = 0.8 and a Ab = 0.8. Silica activities from equilibrium 6 were calculated with Unitherm, and the AUNIlF surfaces were calculated with the QUIlF program. reference reactions of QUIlF and AUNIlF are bold; all reaction curves were calculated at P = 1 bar. ...
FIGURES | View All (6)
Journal Article
Journal: Economic Geology
Published: 01 September 2018
Economic Geology (2018) 113 (6): 1359–1382.
... reflect sulfidation, whereas path 2 could reflect the condensation of a H 2 Te vapor, and path 3 a combination of the two processes. The diagrams were constructed using the program Unitherm ( Shvarov, 2011 ) with some of the thermodynamic data by Mills (1974) , Afifi et al. (1988) , McPhail (1995...
FIGURES | View All (16)
Journal Article
Journal: Geology
Published: 01 February 2017
Geology (2017) 45 (2): 167–170.
... data are listed in Table DR3. The HCh program coupled with the Unitherm database was used for thermodynamic modeling ( Shvarov and Bastrakov, 1999 ). Bulk-rock compositions used in the modeling were derived from Otago Schist and Golden Bar pit samples ( Hu et al., 2015 ). The chemical components...
Journal Article
Published: 01 July 2022
Russ. Geol. Geophys. (2022) 63 (7): 789–801.
... was carried out at 25 °C and 1 bar total pressure using the HCh computer code ( Shvarov, 2008 ), which included the UNITHERM consistent thermodynamic database and data from ( Tagirov et al., 2006 ; Palyanova, 2008 ). We modeled the heterophase ten-component system H 2 O–Ca–Si–Cl–C–S–Fe–Ag–Au, including...
FIGURES | View All (8)
Journal Article
Published: 01 September 2020
Russ. Geol. Geophys. (2020) 61 (9): 964–975.
...” software ( Shvarov, 2008 ) and the consistent thermodynamic database “UNITHERM”. We modelled the heterophase 19-component system H 2 O–Na–Ca–Mg–K–Sr–Ba–Si–Al–Cl–C–S–Fe–Mn–Ag–Au–Cu–Zn, including species in solution, minerals and gases. The initial information was analytical data on the mineral and chemical...
FIGURES | View All (8)