Kinda cool. I like the idea of a shape in layers of rocks. It doesn't have to be empty either. It would still work if you filled in the face with different coloured layers. (That's how rocks actually work... they fill a holes in the layers below them.)
I'm thinking that the face in the design is a little too literal. I really like the layered rock idea. If you google stratigraphic diagrams you'll get an idea of how complex they can be. I'm not sure how to transform that into a logo, but that was sort of what I had in mind when I launched the tourney.