Microscopic teeth of primitive, boneless, eel-like animals, similar to modern hagfish, that lived in many of the world's oceans from the Cambrian through Triassic Periods of geologic time (550 to 210 million years ago).
Publication (PDF format) in three parts on the biostratigraphy and lithostratigraphy of the Ibexian Series in the North American Ordovician, with sections on the southern Egan Range, Nevada and the biostratigraphy of the eastern Great Basin.
Links to USGS capabilities in paleontological analyses of fossils such as mollusks, diatoms, palynomorphs, ostracodes, calcareous nannofossils, etc. Includes descriptive information, technique, equipment, and contacts for each fossil group.
U.S. Department of the Interior |
U.S. Geological Survey