Brian Farrell

Hi Olivia, If the above link doesn't work it may be that something is wrong with your HASP installation, or that HASP is not starting. Try going to the search box (click on the Windows icon) and type in services, then press enter. You should see a list of various services - look for Hasp License Manager. Click on that and a small window should come up. Look for where it says Service status - ideally it should say started. You might also try running the HASP installer by itself. Paste the text below into your search box and follow the installation instructions. I think it's normal to get a message asking if the the file was installed correctly - if everything seems ok click "the file was installed correctly," and then try revisiting the link from Tom. If the link works click on the HASP keys and diagnostics buttons and send screenshots to my email. If you get another sort of error, please send that my way. C:\Program Files (x86)\Gwb\Hasp\haspdinst -i Hope this helps, Brian Farrell Aqueous Solutions (makers of the GWB)

Hi, I was able to get a pH of about 4.4 using a fucagity of 10, so it's a little closer. Scanning through the paper it looks like the equilibrium calculations were only simulated at discrete points (fugacity = 10, 8, 6, ...) and then the mineral assemblages were titrated in. So I constrained the CO2(g) fugacity directly at the beginning and then added in minerals. It seems to be closer to the paper results, except at very low fugacity. You might try contacting the authors to see if they could provide the exact script they used. Unfortunately I couldn't find any sort of data repository with such information. Best of luck. Brian React_CO2.txt.rea

Hi, could you attach a script of yours and the paper you reference so I can compare? Thanks, Brian Farrell

Hi David, To the best of my knowledge water is generally modeled in the liquid phase. In Act2 or Tact, for instance, the activity of water (which is close to 1 in dilute solutions and decreases with increasing ionic strength) can be used as a constraint. In SpecE8 or React, (which perform speciation and reaction path calculations, respectively) water activity is calculated based on the ionic strength and temperature of your system. The fugacity of steam (water vapor) is also calculated and appears in the output results. This fugacity represents the partial pressure of an external gas buffer (large reservoir) in equilibrium with your fluid, if such a gas phase were to exist. The fugacity of steam cannot be set as a constraint. Hope this helps. Brian

Hi, This is the forum for The Geochemist's Workbench. You want to go to the main forum page https://www.rockware.com/forum/index.php?showforum=12 and then click on the Rockworks forum, where you can repost this question. Brian

Hi David, Act2 using its default thermo databases can generate diagrams up to 300 C, at pressures of 1 atm up to 100 C, and following the steam saturation curve thereafter. Above 100 C, then, water is still liquid, unless you specify a lower pressure (which you did in your last diagram). The effect of pressure in Act2 influences only the position of water stability limits and the stability of gas phases. Your diagram is entirely composed of minerals, however, so keeping the pressure at 1 bar doesn't really do anything. I also wonder how useful the x-axis you have chosen is - it seems to be more of a mathematical abstraction than a chemical reality. From my understanding water activity should vary from 0 to 1, so it seems Magnesite and Brucite would be the only likely phases. This isn't exactly answering your original question but you might try a different sort of diagram (diagram Mg++ in Tact vs T and f CO2, or in Act2 vs f CO2 and pH or activity Mg++). You can set an activity for water or a pH in any of these diagrams. Hope to have helped. Brian

Hi Tam, You mentioned that your diagram was Eh vs log a Mn++, but your text file has values listed for pH, not Eh. The scatter data categories must match what you have on your diagram. If you have Eh and pH data, I might try several diagrams to see which is most meaningful (Eh vs pH, fixed a Mn++; Eh vs. Mn++, pH fixed; pH vs Mn++, Eh fixed). Hope that helps. Brian

Hi Tam, You'll want to take a look at the Scatter Data Appendix in the Reference Manual, which you can get to by clicking on the Help tab in Act2. Make sure your two columns are spelled correctly - Mn++ and Eh, and that for Mn++ the data is entered as log activity. Could you post a script for your Act2 diagram and text file so we can try to troubleshoot this? Btw, which version of GWB are you using? 8.0 uses the Geochemist's Spreadsheet which makes adding scatter data really simple, although a text editor like notepad works just fine. Brian Farrell