VFE: Fossil identification and use in correlation

Part 1: learn the relevant fossil taxa

This webpage is your identification guide so you can learn to recognize each fossil species. Each fossil’s name (usually genus or ichnogenus, sometimes genus and species) is given, plus any relevant taxonomic or anatomical information, followed by its geologic range (the time during which it is found in the geologic record, i.e., the time between its first instance and its last instance).

In reviewing these images, your goal is to get familiar with the different fossils, so you can then recognize them in Part 2 of this VFE, and thereby use their geologic ranges to figure out how old a sequence of sedimentary strata are.

Graptolites

Glossograptus, lower to middle Ordovician:

Arthropods

Elraithia, trilobite, Cambrian:

Eurypterus, eurypterid, note: cephalon (head) only, Silurian:

Krausella, ostracode, Ordovician to Silurian:

Crane fly, insect (family Tipulidae), Eocene to modern:

Beetle, insect (family Coleoptera), Pennsylvanian (Carboniferous) to modern:

Mollusks

Turitella, gastropod, Cretaceous to modern:

Nautiloid, cephalopod, Devonian:

Ammonite, cephalopod, Jurassic to Cretaceous:

Chesapecten nefrens, scallop (bivalve), Miocene:

Chesapecten jeffersonius, scallop (bivalve), Pliocene:

Foraminifera

Schwagerina, fusulinid foraminiferid, Permian:

Cribratina, textularid foramaminiferid, Cretaceous (Albian):

Brachiopods

Mucrospirifer, articulate brachiopod, Devonian:

Vertebrates

Knightia, fish (vertebrate), Eocene:

Ediacaran fauna

Pteridinium, unknown group (sea pen?), Precambrian (Ediacaran):

Trace fossils

Zoophycos, trace fossil (feeding trace of a worm?), Paleozoic:

Cruziana, trace fossil (trilobite crawling trace), Cambrian-Permian (Paleozoic):

Skolithos, trace fossil (vertical “worm” burrow), Cambrian-modern:

Okay, now that you have learned the fossils, it’s time for Part 2, where you will apply your knowledge to a stratigraphic cross-section of a hypothetical region