| The prominent outcrops of the Middle Ordovician Antelope Valley Limestone immediately north of the mouth of Ordovician Canyon, Nevada, yield common to abundant silicified invertebrate fossils, including brachiopods (arguably the most common fossil type encountered), echinoderm debris, trilobites, sponges, ostracods, conodonts, bryozoans, pelecypods, cephalopods and gastropods. Note the seeker of Ordovician paleontology at lower right-center. |