Calvert Formation

The Calvert Formation is a geologic formation in Maryland, Virginia, and Delaware. It preserves fossils dating back to the early to middle Miocene epoch of the Neogene period. The formation is a destination for amateur fossil hunters as well as professional paleontologists. It is one of the three formations which make up the Calvert Cliffs, all of which are part of the Chesapeake Group.

Calvert Formation Stratigraphic range: Miocene
Fossils from the Calvert Formation, Zone 10, Calvert Co., MD (Miocene)
Type	Formation
Unit of	Chesapeake Group
Underlies	Choptank Formation
Overlies	Old Church Formation
Location
Region	Maryland, Virginia, Delaware
Country	United States
Type section
Named for	Calvert County

Fossils

The Cavert Formation is extremely fossiliferous. Some of the fossil species represented include the following:[1][2]

Carcharocles megalodon partially buried in gravel along the Calvert Cliffs, Maryland

Sharks

• Carcharocles megalodon
• Carcharocles chubutensis
• Carcharodon hastalis
• Isurus oxyrhincus
• Physogaleus contortus
• Physogaleus hemmooriensis
• Galeocerdo aduncus
• Carcharhinus
• Hemipristis serra
• Squatina sp.
• Squalus sp.
• Echinorhinus blakei
• Notorhyncus cepedianus
• Hexanchus gigas
• Carcharias
• Carcharoides catticus
• Isurus retroflexus
• Parotodus benedeni
• Alopias vulpinus
• Alopias grandis
• Alopias palatasi
• Cetorhinus
• Rhincodon sp.
• Negaprion brevirostris
• Rhizoprionodon
• Sphryna laevissima
• Mustelus sp.
• Scyliorhinidae sp.

Rays and other Cartilaginous Fish

• Mobula pectinata
• Mobula fragilis
• Mobula loupianensis
• Plinthicus stenodon
• Rhinoptera cf. R. studeri
• Aetobatus arcuatus
• Pteromylaeus sp.
• Dasyatis probsti
• Dasyatis rugosa
• Pristis sp.
• Edaphodon sp.
• Chimaera sp.

Bony Fish

• Acipenseridae indet.
• Bagre sp.
• Brotulasp.
• Pogonias sp.
• Sciaenops sp.
• Tautoga sp.
• Acanthocybium cf. solandri
• Thunnus sp.
• Istiophoruscf. platypterus
• Ranzania grahami
• Ranzania tenneyorum
• Ariopsis stauroforus
• Trisopterus sculptus
• Micromesistius cognatus
• Prionotus
• Lophius sp.
• Paralbula dorisiae
• Morone
• Lophokatilus ereboorensis
• Rachycentron sp.
• Pomatomus sp.
• Lagodon sp.
• Micropogonias sp.
• Sphyraena sp.
• Sarda sp.
• Makaira cf. nigricans
• Chilomycterus sp.

Cetaceans

• Aglaocetus sp.
• Squalodon calvertensis
• Eurhinodelphis sp.
• Parietobalaena palmeri
• Eobalaenoptera harrisoni
• Cephalotrophis coronatus
• Araeodelphis
• Cetotherium
• Zarhachis flagellator
• Pelocetus
• Xiphiacetus

Pinnipeds

• Callophoca obscura

Crocodilians

• Thecachampsa antiquus
• Thecachampsa sericodon

Invertebrates

• Chesapecten nefrens
• Chesapecten coccymelus
• Isognomon sp.
• Ecphora
• Architectonica trilineata

Terrestrial Mammals

• Cynarctus marylandica
• Tomarctusbrevirostris
• Gomphotherium calvertensis
• Hipparion cf. phosphorum
• Amphicyon cf. frendens
• Amphicyon intermedius
• Aphelops sp.
• Archaeohippus cf. blackbergi

Birds

• Mergus miscellus
• Morus loxostylus
• Miocepphus

See also

• List of fossiliferous stratigraphic units in Virginia
• Paleontology in Virginia
• Paleontology in Maryland
• Calvert Cliffs State Park
• List of fossiliferous stratigraphic units in Maryland
• Chesapeake Group

References

1. Godfrey, Stephen J., ed. (2018-09-25). "The Geology and Vertebrate Paleontology of Calvert Cliffs, Maryland, USA". Smithsonian Contributions to Paleobiology (100): 2–274. doi:10.5479/si.1943-6688.100. ISSN 1943-6688.
2. "Paleobiology Collections Search". collections.nmnh.si.edu. Retrieved 2020-08-14.