Ordovician. The Cincinnatian and the Richmondian Invasion

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1 Ordovician The Cincinnatian and the Richmondian Invasion P. David Polly Department of Geological Sciences Indiana University Bloomington, Indiana USA The Cincinnatian (painting by John Agnew from A Sea Without Fish: Life in the Ordovician Sea of the Cincinnati Region, D.L. Meyer and R.A. Davis, Indiana University Press.

2 Objectives 1. The Ordovician system in Indiana 2. Cambrian and Ordovician life 3. Taconic Orogeny and the formation of the Cincinnati Arch 4. Paleogeography of the Cincinnatian in Indiana 5. Facies 6. Cincinnati School of paleontology 7. Ordovician life 8. The Richmondian invasion and the end-ordovician extinction

3 Bedrock and Physiography Pennsylvanian Youngest (300 mya) Ordovician Silurian Devonian Mississippian Oldest (470 mya) Bedrock Geology of Indiana H. H. Gray (data compiler). Indiana Geological Survey. Map of Indiana showing physiographic divisions. 2001, by Henry Gray. Indiana Geological Survey.

4 Ordovician Rock Units Three main formations: Kope Fm Dillsboro Fm Whitewater Fm Global stage: Katian NA series: Cincinnatian Sequence: Tippecanoe Age range: mya

5 Cambrian: Burgess Shale, British Columbia A classic soft-preservation Middle Cambrian site 505 million years Hallucigenia Anomalocaris Wolcott Quarry, British Columbia Wiwaxia

6 Evolution of Trophic Levels and Evolutionary Arms Race Pre-vendian: primary producers (stromatolites) Vendian / Ediacaran: primary producers, soft bodied animals, few scavengers, few grazers, few predators. Earliest Cambrian: primary producers, soft and shelly bodied animals, some grazers, some scavengers, few predators. Middle Cambrian: many shelly bodied animals, many grazers, scavengers, predators, all bottom dwelling, move into intertidal waters. Ordovician: first floating, swimming, and burrowing animals. Three-fold increase in number of species. Most dramatic increase in diversity recorded during geologic history. Shells, spines, and other skeletal parts, as well as swimming and burrowing, evolved in the context of increasing predation

7 Bedrock Geology of Indiana H. H. Gray (data compiler). Indiana Geological Survey. Madison, Indiana (photos by PD Polly)

8 Regional structure

9 A typical orogenic episode Oceanic Side Continental side

10 Modern Orogeny Mountains and Island Arcs Eurasian Plate China Korea Foreland Basin Japan Trench Pacific Plate

11 The Taconic Orogeny (Cambrian through Ordovician) Subduction zones shown in black From Potter, 2007, Exploring the Geology of the Cincinnati/Northern Kentucky Region. Kentucky Geological Survey, Special Publication 8.

12 The Taconic Orogeny Late Ordovician Late Cambrian Early Cambrian

13 Taconic orogeny shifted blocks of Precambrian basement to form Cincinnati Arch (Early Cambrian through Ordovician) From Potter, 2007, Exploring the Geology of the Cincinnati/Northern Kentucky Region. Kentucky Geological Survey, Special Publication 8.

14 Cross section through the Cincinnati Arch From Potter, 2007, Exploring the Geology of the Cincinnati/Northern Kentucky Region. Kentucky Geological Survey, Special Publication 8.

15 Cincinnatian (Late Ordovician) paleogeography Meyer and Davis, A Sea Without Fish. IU Press, Bloomington.

16 Marine environments or facies of the Cincinnatian A facies is a body of rock that has specific characteristics (sedimentary or faunal) because it was formed under specific sedimentary conditions. Meyer and Davis, A Sea Without Fish. Indiana U. Press, Bloomington.

17 US 421 road cut at Madison, Indiana Contact between Dillsboro and Whitewater formations Whitewater Fm. Dillsboro Fm. Photo 2008 by P. David Polly

18 Tabulate coral heads at the base of the Saluda Limestone (Whitewater Fm.) Photos 2008, P. David Polly

19 Fossiliferous localities in the Cincinnati Arch Stigall, Using GIS to assess the biogeographic impact of species invasions during the Richmondian invasion. Palaeontologia Electronica, A.

20 The Cincinnati School Early paleontologists of the Ordovician ( ) Charles Schuchert Amateur collector, later Smithsonian scientist and Professor at Yale University Samuel A. Miller Attorney and scientist August Foerste (left), Dayton school teacher , and Ray Bassler (right), Smithsonian scientist , with Amadeus Grabau (center) New York paleontologist and stratigraphic geologist.

21 Charles Lyell Visits Cincinnati and the Ordovician* rocks there in 1842 (*thought of as Silurian in age at the time) After seeing at Cincinnati several fine collections of recent and fossil shells in the cabinets of Messrs. Buchanan, Anthony, and Clark, I examined with care the quarries of blue limestone and marl in the suburbs. The organic remains here are remarkably well preserved for so ancient a rock, especially those occurring in a compact argillaceous blue limestone, not unlike the lias of Europe. On both sides of the Atlantic, these ancient marine formations are characterized by a prodigious development of one peculiar family of mollusca, called brachiopoda. --shells, which as they inhabit deep water, are little known, and have received no common name in our language. -Lyell, 1845 Travels in North America Lyell later visited David Dale Owen in New Harmony in Sir Charles Lyell British geologist, author of Principles of Geology

22 Life in the Cincinnatian Seas Crinoid (Echinodermata) Sea star (Echinodermata) Nautiloid (Mollusca) Jellyfish (Cnidaria) Horn coral (Cnidaria) Bryozoan colony (Bryozoa) Trilobite (Arthropoda) Brachiopods (Brachiopoda) The Cincinnatian (painting by John Agnew from A Sea Without Fish: Life in the Ordovician Sea of the Cincinnati Region, D.L. Meyer and R.A. Davis, Indiana University Press.

23 Sepkoski s three Evolutionary Faunas and five mass extinctions Sepkoski, J. J., Phylogenetic and ecologic patterns in the Phaneroic history of marine biodiversity. Pp in N. Eldredge (ed.), Systematics, Ecology, and the Biodiversity Crisis. Columbia University Press, New York.

24 The Richmondian Invasion Change in fossils in Late Ordovician related to rise in sea level Stigall, Using GIS to assess the biogeographic impact of species invasions during the Richmondian invasion. Palaeontologia Electronica, A.

25 Global Sea Level through the Phanerozoic From Hallam and Vail Low sea level in Cambrian Rising through the Ordovician Falling starting at Late Ordovician

26 Middle Ordovician (470 mya) Transcontinental Arch Taconic Mountains (c) Ron Blakey (

27 Late Ordovician (450 mya) Taconic Mountains (c) Ron Blakey (

28 Summary Cincinnatian is a North American chronostratigraphic unit of Late Ordovician. Taconic Orogeny created first mountain range along what is now the east coast during Cambrian and into Ordovician. Cincinnati arch and associated basins formed during Taconic Orogeny. Facies are different, contemporaneous sedimentary and life environments, often related to water energy level and water depth. Different organisms live in different facies and the study of organisms across space and through time is both complicated and scientifically rewarding. Changes in sea level changed water depth, facies, and geographic barriers, allowing the Richmondian Invasion of the Cincinnatian region. Richmondian Invasion increased diversity by adding new species to paleocommunity. End Ordovician extinction later decreased diversity.