It's only a model! *Shhh!*
Joking aside, this is, what, a computer model? So they could make it pretty much whatever color they want, yeah? If they wanted to, they could have adjusted it to the same false-color blue that the "blueberries" were made to look, despite being hematite concretions. And what if they'd made it rainbow-colored by elevation?
Anywho, let's not read too much into it, eh? =oP
