What could have been a walk in the park becomes a whole lot messier when every thickness map within reach features a myriad of different color contours rather than a nice and tidy little color palette. Or is it just me looking at the wrong places? Well fortunately, when taking a closer look there turned out to be more system in this color anarchy then what seemed at first ("anarchies" often work that way), so it was eventually possible to narrow things down to a handful of specific contours, each representing a thickness.

However, there are problems with this approach, most notably; the pure colors (red, yellow, cyan and blue in this instance) merged with and were eaten by their less pure neighbours so to speak. This effect becomes particularly visible at low elevations where the slope is steeper and the different colors are crammed tighter together. Then, for some reason (I'm tempted to say god knows why, but I'm not sure he does this time) there turns out to be 36 different contours, for one 32 would have fitted perfectly into their color system, as opposed to the current solution which tries to divide 256 on 9, but more importantly it would allow each contour to represent a leap of exactly 100 meters, as opposed to 88,1m which I got from pixel counting their color scale (which by the way measures 241, a prime). Is this because 88 meter fits some margin of error or something like that, or do they just want to mess up the diagrams of excel noobies like me?

Either way I have managed to produce a couple of diagrams that resembles those who were requested, although it is not volume vs elevation, which I agree would be better, but rather volume vs thickness. I'll do the elevation as well, but if someone happens to jump across such a map that doesn't feature every possible RGB combination, that would be helpful and it would enable me to do a bit more than just setting a crude line at approximately 2000m (the same goes for the thickness map of course). Note that I have been treating the individual coutures as ranges which means the volume calculations are based on the medium of these ranges, please let me know if I've gotten that wrong. In this calculation the 2000 meter boundary splits the volume 35/65, give or take a percentage or two.

*Click to enlarge.*