Three sweet advertisements for the Nissan Xterra, found via Did You Just Eat Sofa Pizza? and posted with the comment, "geology cake! looks so goooood! someone make for me nao!!" Now I'm not a fan of advertising, but if those are in fact real cakes- and I have my doubts- I heartily approve. And despite the punny title, that "layer-cake geology" (yes, that is how geo-types refer to the kind of flat-laying strata seen above) wouldn't be a very good model for the kinds of places one would find marble. From ReBecca's shared items, this is fer sure a real cake, and despite being labeled a "Zebra Cake," would be a much better model for a marble cake. Though the recipe still doesn't call for rock flour.