Looking southwest across Cerro Colorado toward the Sierra Pinacate. La Laja cinder cone and its flows, evidently the youngest eruption in the Pinacate, are the dark rocks in the middle distance. Cerro Colorado is a tuff cone whose crater floor is somewhat deeper than the pre-existing ground surface and which is built of tuff consisting of ejected gravel and chilled bits of magma (juvenile ash). A strong north wind (blowing from right to left here) evidently accompanied the cone-building eruptions.