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Hi, I'm trying to model anorthite dissolution in Archean-like seawater under a wide range of w/r (kg:kg) conditions. I would like to run models for w/r = 0.001 - 10,000 (expecting to see a dilution curve at high w/r). However, I can't get the model to converge below w/r ~ 0.33 (i.e., An = 0.033 kg, H2O = 0.1 kg). I attached a copy of my input script. Can I get some advice on what I'm doing incorrectly? Thanks in advance! -- Adam input_script_An_archean_var_wr_allsupp.txt

Hi, I'm using React to run dissolution experiments of minerals under Archean seawater conditions. In Gtplot, I noticed that for all of my model runs, plotting "mass reacted" (of the primary mineral) vs Rxn Progress shows a straight line that ends when the y-coordinate reaches the input mass. For example, if I run react 100 g Anorthite and plot "Mass reacted, Anorthite (g)" vs Rxn progress, the line goes from 0 to 100 g (see attached plot). Does this mean all 100 g have been dissolved and are now in solution with no primary mineral remaining? Or can React model a dynamic equilibrium where, for example, you have seawater sitting on top of a crust (made of feldspar, olivine, etc) and the crust dissolves until it reaches saturation?

Hi, I am trying to model calcite dissolution in DI water open to the atmosphere. My model is nearly correct except that the initial pH is only reaching about 9.6 when I need it to be reaching about 10 initially. I believe that the problem may stem from my basis fugacity of CO2 in the system. Currently it is set to log fugacity of -3.5 but since the water I use for the experiment comes from a jug, is it possible that the initial fugacity of water is lower? Or, is it possible that the fugacity of CO2 in the kinetic reaction should be set to a different value other than log fugacity of -3.5? I have tried playing with these values but was unable to achieve a higher initial pH. I have attached my expiremental results as well as my model. Let me know if you have any suggestions of how to raise the initial pH of the solution. Thank you, Robin Calcite only.rea Calcite Expiremental.xlsx

I am working on a final project in a course, and am having some difficulty interpreting the output from GWB. My input files are below. My question boils down to how geochemist workbench deals with the "time" component on the basis species page, and the "reactants times" on the reactants page when dealing with a flow-through model. I have found the residence time of a conservative tracer in my column, which is ~164 minutes. Over the course of my column experiments, which typically last ~5 days, I react ~44 pore volumes. To incorporate this information into the model, I have used both 164 minutes (residence time) and 120 hours (average experiment time). On the reactants page, I said to react 44 times. But I don't know what GWB is reacting in that case. If someone would be able to advise me on the best way to incorporate all the known data into my system, I'd appreciate any help. In the end, I want to run a series of these to see how long it takes to dissolve 15.59 cm^3 or 23 grams of silicate glass. Thanks, MC SiDiss1.rea

​Dear forum, ​as I calculate anorthite dissolution using a custom rate law in Xt1 I wonder about the reference of the kilograms in the unit of the reaction rate (rxn rate) in the text output file of GWB, which is mol/kg sec. So my question is if the kilograms refer to one kilogram of water? Thanks for your help and kind regards, Christoph​