Shiprock gives the impression of having been volcanically thrust out from the sands of the Mancos desert, but this isn’t the case. Shiprock is indeed a volcano but of a class called a “diatreme”, having formed explosively from gas-charged magma escaping at great velocity. It possessed a crater at the surface called a “maar”, but erosion has long since removed it along with much of the sedimentary strata through which it erupted.