The Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 Jeffersonville Limestone is a mapped bedrock

Bedrock

In stratigraphy, bedrock is the native consolidated rock underlying the surface of a terrestrial planet, usually the Earth. Above the bedrock is usually an area of broken and weathered unconsolidated rock in the basal subsoil...

 unit in Indiana

Indiana

Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...

 and Kentucky

Kentucky

The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...

. It is highly fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

iferous.

Description

The Jeffersonville is a coarse grained, dark gray, thick bedded, fossiliferous limestone.

R. D. Perkins (1963) divided the Jeffersonville into five zones based on petrology and fossil content, and these are summarized below (in stratigraphic order):

• Paraspirifer acuminatus zone (top)
• fenestrate bryozoan-brachiopod zone
• Brevispirifer gregarius zone
• Amphipora-zone
• Coral zone (base, overlies Geneva Dolomite or Louisville Limestone)

Fossils

The Jeffersonville Limestone is well known for its fossils, including the well-exposed corals, many in life positions, at Falls of the Ohio.

Edward Kindle described many species from the Falls of the Ohio in 1899:

• Brachiopod
  Brachiopod
  Brachiopods are a phylum of marine animals that have hard "valves" on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection...
  
  s: Atrypa
  Atrypa
  Atrypa also known as lamp shell is an extinct genus of brachiopod that lived from the Late Ordovician to the Carboniferous and occurs abundantly as fossils in marine rocks...
  
   aspera, A. reticularis, Chonetes mucronatus, C. yandellanus, Cyrtina hamiltonensis, Derbya keokuk, Discina
  Discina (brachiopod)
  Discina is a brachiopod genus in the family Discinidae. It is an inarticulate form present in the Carboniferous....
  
  sp., Leiorhynchus quadricostatum, Orthis iowensis (?), O. livia, Pentamarella arata, Pentamerus
  Pentamerus
  Pentamerus is a prehistoric genus of brachiopod that lived from the Silurian to the Middle Devonian in Asia, Europe, and North America.-External links:* in the Paleobiology Database...
  
   nueleus, Productella subamleata var. catarafla, Productus burlingtonensis, Spirifer acuminatus, S. arctisegmentus, S. byrnesi, S. euruteines, S. gregarius, S. keokuk, S. oweni, S. segmentus, S. subattenuatus, Stropheodonta (now Strophodonta) arctostriatus, S. demissa, S. hemispherica, S. perplana, S. varicosus, Syringothyris texta, Terebratula lincklaeni
• Rostroconch
  Rostroconchia
  The Rostroconchia is a class of extinct molluscs dating from the early Cambrian to the late Permian. They were initially thought to be bivalves, but were later given their own class. They have a single shell in their larval stage, and the adult typically has a single, pseudo-bivalved shell...
  
  : Conocardium trigonale (?), C. cuneus
• Coral
  Coral
  Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
  
  s: Blothorphyllum decorticatum, Conularia micronema, Cyathophyllum rugosum, Diphyphyllum sp., Favosites
  Favosites
  Favosites is an extinct genus of tabulate coral characterized by polygonal closely packed corallites . The walls between corallites are pierced by pores which allowed transfer of nutrients between polyps....
  
   hemisphericus, Michelinia cylindrica, Thecia minor http://www.yale.edu/ypmip/taxon/anthozoa/tabulata/150572.html, Zaphrentis giganteus, Z. ungula
• Gastropods
  Gastropoda
  The Gastropoda or gastropods, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. The class Gastropoda includes snails and slugs of all kinds and all sizes from microscopic to quite large...
  
  : Callonema bellatulum, C. imitator, Platyceras dumosum, Platvstoma lineatum, Trochonema rectilatera, Holopea sp., Pleurotomaria
  Pleurotomaria
  Pleurotomaria is a genus of sea snails, marine gastropod mollusks in the family Pleurotomariidae.-Species:Species within the genus Pleurotomaria include:Species brought into synonymy :...
  
  sp., Turbo shumardi
• Bivalves
  Bivalvia
  Bivalvia is a taxonomic class of marine and freshwater molluscs. This class includes clams, oysters, mussels, scallops, and many other families of molluscs that have two hinged shells...
  
  : Actinopteria boydi, Aviculopecten sp., Glyptodesma occidentale, Macrodon sp. (?), Modiomorpha affinis, M. mytiloides, Ptychodesma sp.
• Trilobite
  Trilobite
  Trilobites are a well-known fossil group of extinct marine arthropods that form the class Trilobita. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period , and they flourished throughout the lower Paleozoic era before...
  
  s: Proetus canaliculatus, P. crassimarginatus, P. microgemma (see Proetidae
  Proetidae
  Proetidae is a family of trilobites. The first appeared in the Upper Ordovician, and were among the last surviving trilobites, occurring until the Carboniferous. The family Proetidae contains the following...
  
  ), Dalmanites
  Dalmanites
  Dalmanites is a genus of trilobite in the order Phacopida.The trilobites of this genus have slightly convex exoskeletons with an average diameter of 4–7 cm . The cephalon is semicircular or parabolic. The glabella is often pear-shaped, and tapers outward toward the front...
  
   anchiops var. sorbrinus, D. selenurus

Campbell and Wickwire (1955) listed the following species in the Jeffersonville from outcrops in the vicinity of Hanover, Indiana

Hanover, Indiana

Hanover is a town in Hanover Township, Jefferson County, Indiana, along the Ohio River. The population was 3,546 at the 2010 census. Hanover is the home of Hanover College, a small Presbyterian liberal arts college. Hanover is also the home of Southwestern High School...

:

• Corals: Heliophyllum halli, Hexagonaria prisma, Favosites turoinatus, F. limitaris, Emmonsia emmonsi, E. epidermatus, Synaptophyllum simcoense, Homalophyllum exiguum, Zaphrentis phyrgia, Blothrophyllum promissum, Alveolites sps., Michelinia sps.
• Bryozoa
  Bryozoa
  The Bryozoa, also known as Ectoprocta or commonly as moss animals, are a phylum of aquatic invertebrate animals. Typically about long, they are filter feeders that sieve food particles out of the water using a retractable lophophore, a "crown" of tentacles lined with cilia...
  
  : Sulcoretepona gilberti, Polypora shumardi
• Gastropods: Platyceras dumosum, Bellerophon patulus
• Brachiopods: Paraspirifer acuminatus, Brevispirifer gregarius, Fimbrispirifer divaricatus, Meristina nasuta, Megastrophia hemispherica
• Bivalves: Turbinopsis shumardi, Glyptodesma occidentali, Conocardium cuneus
• Crinoid
  Crinoid
  Crinoids are marine animals that make up the class Crinoidea of the echinoderms . Crinoidea comes from the Greek word krinon, "a lily", and eidos, "form". They live both in shallow water and in depths as great as 6,000 meters. Sea lilies refer to the crinoids which, in their adult form, are...
  
  : Nucleocrinus verneuili
• Trilobites: Phacops rana
  Phacops rana
  Phacops rana is a species of trilobite from the middle Devonian period. Their fossils are found chiefly in the northeastern United States, southwestern Ontario, and in Morocco.-Physiology:...
  
  , Anchiops anchiops
• Cephalapods: Gyroceras
  Gyroceras
  Gyroceras is an extinct genus of prehistoric nautiloid. The nautiloids are a subclass of shelled cephalopods that were once diverse and numerous but are now represented by only a handful of species.-References:...
  
   indianense

Other trilobites include the following: Arctinurus

Arctinurus

Arctinurus boltoni was a lichid trilobite of the mid-Silurian. This trilobite reached about eight inches in length, though the normal adult carapace was about four inches. It lived in moderately deep-water in semi-tropical regions. Arctinurus fossils have been found in Europe and North America...

sp., Anchiopsis anchiops, Anchiopsis tuberculatus, "Calymene" platys, Coronura aspectans, C. myrmecophorus, C. helena, Crassiproteus clareus, C. crassimarginatus, C. macrocephalus, Greenops

Greenops

Greenops is a mid-sized Devonian trilobite of the order Phacopida, subfamily Asteropyginae.They are mainly reported from the mid-Devonian Hamilton Group of upstate New York and southwestern Ontario...

 kindlei, Odontocephalus bifidus, O. magnus, Odontochile pleuroptyx, Phacops

Phacops

Phacops is a genus of trilobite in the order Phacopida, family Phacopidae that lived in Europe and North American in the Silurian and Devonian periods. It was a rounded animal, with a globosa head and large eyes, and probably fed on detritus...

 nasutus, Phacops pipa, Trypaulites calypso

Ostracod

Ostracod

Ostracoda is a class of the Crustacea, sometimes known as the seed shrimp because of their appearance. Some 65,000 species have been identified, grouped into several orders....

s were documented by Kesling and Peterson in 1958. Genera identified include: Abditoloculina, Adelphobolbina, Ctenoloculina, Flaccivelum, Hollina, Hollinella, and Subligaculum.

The Blastoid

Blastoid

Blastoids are an extinct type of stemmed echinoderm. Often called sea buds, blastoid fossils look like small hickory nuts. They originated, along with many other echinoderm classes, in the Ordovician period and reached their greatest diversity in the Mississippian subperiod of the Carboniferous...

s Codaster alternatus and Codaster pyramidatus, among others, were identified by Cline and Heuer in 1950 at Falls of the Ohio.

Notable Exposures

Type locality is at Falls of the Ohio State Park

Falls of the Ohio State Park

Falls of the Ohio State Park is a state park in Indiana. It is located on the banks of the Ohio River at Clarksville, Indiana, across from Louisville, Kentucky.The park is part of the Falls of the Ohio National Wildlife Conservation Area...

 near Louisville, Kentucky

Louisville, Kentucky

Louisville is the largest city in the U.S. state of Kentucky, and the county seat of Jefferson County. Since 2003, the city's borders have been coterminous with those of the county because of a city-county merger. The city's population at the 2010 census was 741,096...

.

Age

Relative age dating places the Jeffersonville in the lower to middle Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

. Devera and Fraunfelter identified it as Emsian-Eifelian based on coral and foraminifera

Foraminifera

The Foraminifera , or forams for short, are a large group of amoeboid protists which are among the commonest plankton species. They have reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net...

.

External links

• Indiana Geological Survey page on Jeffersonville Limestone
• KYANA Geological Society Devonian page, showing photographs of fossils collected from the Jeffersonville and other formations
• guidebook Silurian and Devonian Geology and Paleontology at the Falls of the Ohio, Kentucky/Indiana, 42nd Annual Meeting of the American Institute of Professional Geologists, fieldtrip guidebook, 2005