Rockport Quarry Limestone

The Rockport Quarry Limestone is a geologic formation in Michigan. It preserves fossils dating back to the middle Devonian period.

Fossil content

Vertebrates The Devonian vertebrate fauna of the Rockport Quarry Limestone is the most diverse in Michigan.

Acanthodians Acanthodians reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images?Machaeracanthus?M. sp.A single specimen (UMMP 13047).

Cartilaginous fish Cartilaginous fish reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesPhoebodusP. cf. P. sophiaeAlpena, Michigan.A tooth.An early elasmobranch.?Tamiobatis?T. sp."At the abandoned Kelly Island Limestone Quarry at Rockport State Park, Alpena County".A single small spine (UMMP 13147).A ctenacanthoid.

Placoderms Placoderms reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesDinomylostomaD. sp.An arthrodire.DunkleosteusD. sp.Rockport Quarry, Alpena County.A single incomplete right anterior ventrolateral (UMMP 16152).An arthrodire.Holonema?H. rugosumA single specimen (UMMP 3898).An arthrodire.H. sp.26 specimens.An arthrodire.MylostomaM. sp.A single specimen (UMMP 13612).An arthrodire.PlacodermiAt the abandoned Kelly Island Limestone Quarry at Rockport State Park, Alpena County.2 specimens (7M, VP. 522.)Placoderms of unknown affinity.ProtitanichthysP. rockportensis59 specimens.An arthrodire.PtyctodusP. sp.A single specimen (UMMP 13045).A ptyctodontid.

Invertebrates Brachiopods Brachiopods reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesChonetesC. mediolatusAlso found in the Bell Shale, Ferron Point Formation and St. Laurent Limestone.PentamerellaP. sp. BBasal 8 inches of the formation.2 specimens.PholidostrophiaP. gracilis gracilisAlso found in the Bell, Ferron Point and Genshaw formations.SchizophoriaS. ferronensisBasal 8 inches of the formation.Also found in the Bell Shale, Ferron Point Formation and Silica Shale.SchuchertellaS. crassaAlso found in the lower Bell Shale, Ferron Point Formation and Arkona Shale.SpinulicostaS. mutocostaAlso found in the Bell, Ferron Point, Four Mile Dam, Beebe School, Thunder Bay and Potter Farm formations.StrophodontaS. extenuata rockportensisLower 8 inches of the formation.TylothyrisT. rockportensisAppears to be endemic to the Michigan Basin.T. subvaricosaAlso found in the Cedar Valley, Milwaukee, Mineola, Bell, Ferron Point, Genshaw, Alpena, Gravel Point, Norway Point and Potter Farm formations.

Bryozoans Bryozoans reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesFenestellidaeSpecies A Species BSpecies CTrepostomataSpecies ASpecies B

Crustaceans Crustaceans reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images Ostracoda PhlyctiscaphaP. rockportensisBasal part of the formation.An ostracod.

Echinoderms Echinoderms reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images Crinoidea "Observed as disaggregated ossicles, ossicles stacked en echellon, and fragments of columnals".

Molluscs Molluscs reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images Cephalopoda "All specimens collected as single-hand specimens". Gastropoda

Sponges Sponges reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesClathrodictyidaeIdiostromatidaeStromatoporidae

Trilobitomorphs Trilobitomorphs reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images Trilobitomorpha 200 m south of the large sinkhole on the west wall of Rockport Quarry.

Plants and algae Plants and algae reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesCalcispheraC. sp. A"Abandoned quarry of the Onaway Limestone Company on the shore of Black Lake".C. sp. B"Abandoned quarry of the Onaway Limestone Company on the shore of Black Lake".RhodophytaIndeterminate200 m south of the large sinkhole on the west wall of Rockport Quarry. Vermiporella"Observed as transverse sections, most specimens now irregular in shape due to crushing".

Cyanophytes Cyanophytes reported from the Rockport Quarry Limestone Genus Species Presence Material Notes Images Genus and species indeterminateIndeterminate "Spherical bodies 3-5 microns in diameter". Oncolite"Some post-depositional crushing of the sample has occurred".Renalcis"Abandoned quarry of the Onaway Limestone Company on the shore of Black Lake".

Foraminifera Foraminifera reported from the Rockport Quarry Limestone Genus Species Presence Material Notes ImagesFamily indet."Found sparsely as solitary individuals in 6 specimens". Nodosinellidae

See also

List of fossiliferous stratigraphic units in Michigan

References