Back to OverviewThe purpose of this lab is to get started working with unix and MELTS. We will be working in the university workstation laboratory for the next two days. The workstations run the operating system Unix and the X-windows windowing system. For those used to Macintoshes or PC's, it takes some getting used to.
When you turn on the monitor (Unix systems are never shut off!!)¸ you see a dialog box with a long list of computer names. Just the first 10 or so of these concern us, the ones labeled zdvmail. These can be used by anybody with an email account at the university. Click on one of these names. This activates the X-window system on the workstation, but logs you into the computer you selected. This is important, since MELTS is only installed as a binary for the DEC alphas that are set up for zdvmail. The computer will offer you a login window where you give your username and your password. Some people will have to log on as me.
When you log on, you will see a variety of windows -- one of these will have a command prompt in it, that looks something like snowj000[berlioz] $ At this command prompt type in:
Netscape -mono &
and Netscape will appear in monochrome mode. MELTS won't coexist with Netscape in color mode. Type in the following to the navigator window in Netscape:
http://merckx.mpch-mainz.mpg.de/
and hit enter. You will now be on my web site. Now click on the link below:
http://www.geology.washington.edu/~ghiorso/MeltsWWW/Melts.html
to open the MELTS web page.
Click here to see the input file we will use for melts. It is a picritic basalt that could easily pass for a primary MORB compositions. Now go back and save it in your home directory as picrite.melts. If you're logged in as me don't bother. Use the File|Save option in Netscape to do this.
Go back to the terminal window and type "Melts &" with a carriage return. From the command menu item select Open…, and when the File Open dialog appears, click on "picrite.melts". Now select Execute/Halt, and watch the fun begin. The main part of the display is an AFM diagram. The two X-Y diagrams give the molar component composition of each phase (the lower window) and the major element composition of the liquid (upper window). Unfortunately, the identities of the various phases and components are not listed. You will have to try to read those off of the text display in the lower left, or guess them.
In order to restart the model, you have to exit the program and restart it from the command line.
Explaining the basic elements of MELTS and how to interpret the output graphs and files is as far as I expect to get today. Next week we will work through some of the examples and exercises in the MELTS home page, and the following week we will work on some real systems.