Sunday, April 24, 2011

Coloring Cross Sections: Adobe Illustrator Paint Groups

A while ago I posted a procedure on how to create a topographic cross section in Adobe Illutrator without vertical exaggeration ("Geologic Cross Sections and Adobe Illustrator").  The procedure used tabular elevation and distance data and Adobe Illustrator.  In that post, I did not explain what to do next.  So here's some more guidance.  Screen captures or a video may come later.
  1. Export your completed geologic map WITH the cross section line(s) from Arc or your chosen GIS to Illustrator-friendly format at 300 DPI.  
  2. Embed or link the AI geologic map file into your cross section Illustrator file.
  3. Rotate and align your newly imported map and a cross section line to the bottom of the profile's distance (X) axis (or at the bottom of the lowest elevation on your profile).  This is where you find out if your profile is at map scale!
  4. Create a new layer, call it "Cross Section Edges"
  5. Select the layer and project lines of appropriate weight (contact vs. fault) from the intersection of the X axis and the map's contacts or faults up through the profile line. 
  6. Begin drawing your beds using strike and dip information, remembering to use apparent dips when necessary.
  7. Be sure that all your lines end at another path.  For example, a contact line might end at the boundary of your profile chart or at a fault.  Do not leave gaps open between any paths.
  8. When you're done drawing all your bedding and faults, select all of your cross section art and turn it into a Live Paint Group
  9. Now Live Paint all the faces and edges!  See Adobe's help for more information.
  10. If you need to use patterns (say, from the FGDC Geologic Map Symbol website) and a unit color, I suggest coloring first, then copy the entire paint group, paste into place, and paint using a pattern.  Hopefully your patterns have transparent backgrounds.
  11. I also suggest creating new layers for every component of your cross section such as legend, title, and other information.
  12. Use the Lock layer tool and smart guides to your benefit!

Wednesday, April 6, 2011

This Quarter: Remote Sensing

This quarter at UC Davis, I'm in a remote sensing class.  The lab instructs on use of ENVI software and principals of remote sensing.  Yes, ENVI is powerful.  No, it does not have a modern interface.  I keep thinking I'm using some throw-back MOTIF graphical user interface.  ENVI has mile-long menus.  This is the only software I've used in recent history that has no obvious organization, and seemingly, very similar submenu categories.  But alas, it appears to be one of the standard software packages for remote sensing, and so I will learn it well.  Too bad ITT charges $200 for an academic license and their website is a nightmare from yesteryear.  ESRI, at least, has an awesome program to encourage use of its software: students in GIS courses taught by in-the-know Professors typically get free one year licenses.  What's up, ITT?

It is unfortunate that  out of thirty students, I appear to be the only geologist taking the course.  I am so very confused about that.  In fact, it is also rare that geology students take GIS courses.  So my job prospects look pretty bright, if this is the rule and not the exception.