Re: Phreeqci questions

["David L Parkhurst" <dlpark@xxxxxxxx>]

You can only operate on one solution at a time. I have added solution
numbers to make clear which solution is which, but the default assignment
of numbers would have been the same. There are two simulation of
evaporation, one with solution 1, one with solution 2.

Note that atmospheric CO2 partial pressure is 10^-3.5. Looking at iron
oxides, you should probably include atmospheric oxygen (10^-0.7 partial
pressure). Hematite is unlikely to form, but goethite is reasonable. You
don't have any manganese in your system, so rhodochrosite could not form.


SOLUTION_SPREAD
    -units    mg/l
 Number                    Description     Temperature        pH    Ca   Mg
 Na      K     Fe  Mn    Alkalinity  S(6)  Cl     Si   N(5)
      1      Kihn-Castilla "Blue Hole"           9.166       7.4   440   35
 14    3.2     20  23           295   930  24    8.8    0.2
      2      Kihn-"Miller's Blue Hole"           9.444       7.6   594   36
  7    2.3   0.07   0           328  1300  16    9.3    0.1
END
USE solution 1
REACTION 1 Evap of Kihn data
    H2O(g)     -1
    50 moles in 1 steps
EQUILIBRIUM_PHASES 1
    Aragonite 0 0
    Calcite   0 0
    CO2(g)    -3.5 10
    O2(g)   -0.7  10
    Dolomite  0 0
    Fe(OH)3(a) 0 0
    Goethite  0 0
    Gypsum    0 0
#    Hematite  0 0
    Jarosite-K 0 0
    Quartz    0 0
    Rhodochrosite 0 0
    Siderite  0 0
PRINT
    -species               false
    -warnings              -1
SELECTED_OUTPUT
    -file                 Kihn.sel
    -reaction             true
    -charge_balance       true
    -percent_error        true
    -saturation_indices   Anhydrite  Calcite  Dolomite  Gypsum
                          Halite
END
USE solution 2
USE reaction 1
USE equilibrium_phases 1
END


David Parkhurst (dlpark@xxxxxxxx)
U.S. Geological Survey
Box 25046, MS 413
Denver Federal Center
Denver, CO 80225

Project web page: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled