THE EARLY PALEOZOIC THE CAMBRIAN 544-505 MY CAMBRIA>>WALES ADAM SEDGWICK 1835 THE ORDOVICIAN 505-438 MY ORDOVICE>>WELSH TRIBE CHARLES LAPWORTH 1879

NEOPROTEROZOIC TO MIDDLE CAMBRIAN STRATIGRAPHIC COLUMN NEOPROTEROZOIC TO MIDDLE CAMBRIAN STRATIGRAPHIC COLUMN. PRINCIPLE LIFE FORMS AND STAGES OF THE EARLY CAMBRIAN PLACEMENT OF BOUNDARY AT THE PHYCODES pedum ZONE, TRACE FOSSIL, @ 544 MY TYPE LOCALITY>>BURIN PENINSULA, NEWFOUNDLAND CAMBRIAN DIVISIONS BASED TRILOBITE ZONES [BIOMERES -INTERVALS OF TIMES BETWEEN TRILOBITE EXTINCTIONS]

PALEOGEOGRAPHY CAMBRIAN CONTINENTS WITHIN 60O OF PALEOEQUATOR GONDWANA TIBET, SE ASIA, ARABIA, AFRICA, AUSTRALIA, ANTARCTICA, S. AMERICA LAURENTIA> RIFT ZONES>PASSIVE MARGINS FLOODING OF INTERIORS DUE TO RIFT SYSTEMS IAPETUS OPENED BET N. AMERICA & EUROPE SUBDUCTION ZONES DEVELOPED LATER

TECTONIC EVENTS Pan-African Orogeny Caledonian-Hercynian Orogeny Appalachian, Caledonian, Hercynian, Urals, Ouachita, Samfrau Overall scenario is coalescence of Pangea during most of the Paleozoic Taconic Orogeny mid to late Ordovician Caledonian Orogeny late Silurian to early Devonian Acadian Orogeny mid Devonian Alleghenian Orogeny late Penn, Permian Hercynian Orogeny - Ouachita Orogeny

PLATE TECTONIC MOVEMENTS FROM THE NEOPROTEROZOIC TO THE DEVONIAN (750 MY TO 370MY) BREAK UP OF RODINIA AVALONIAN OROGENY OPENING OF IAPETUS OPENING OF RHEIC TACONIC OROGENY CLOSING OF IAPETUS ACADIAN OROGENY

The Appalachians Valley and Ridge Blue Ridge Province Inner Piedmont folded & faulted sedimentary rks Blue Ridge Province metamorphosed Precambrian and Paleozoic Rks Inner Piedmont high grade metamorphic rks intruded by granites Charlotte & Carolina Slate Belt metamorphosed & folded late Proterozoic & Cambrian sediments and volcanics

A) Cambro-Ordovician Passive Margin: Sandy Shelf Deposits B) Middle to Late Ordovician Development of Trench Along the Eastern Boundary and Subsequent Closure of the Iapetus Ocean C) Collision of Island Arc and other Accreted (exotic) Terranes with North America in the TACONIC OROGENY

CAMBRIAN PALEOGEOGRAPHY: SHALLOW EPICONTINENTAL SEAS COVERED THE CENTRAL US Earliest Paleozoic time of lowest sea level due to Proterozoic glaciations By middle Cambrian sea had flooded the continent

LITHOLOGIC FACIES OF THE CAMBRIAN The transgression of the Cambrian is visible in the rocks of the Grand Canyon

NEOPROTEROZOIC TO CENOZOIC TRANSGRESSIONS AND REGRESSIONS OBSERVED ON THE CRATON Variable sea level represented sequences of sediments bounded by unconformities on all of the cratons - e.g. Sauk, Tippecanoe

ORDOVICIAN-PALEOGEOGRAPHY Tippecanoe Transgression St. Peter’s Sandstone

The Queenston Clastic Wedge Redbeds coarser towards the source area, Taconic Highlands (4000m)

Early Paleozoic Climates Climates overall warmer than today Continents 600 N & S of equator Arid to sub arid environments 450 N & S of equator Redbeds (alluvial) 300 N & S of equator Tropical reefs 300 N & S of equator Cambrian Archeocyathids; Ordovician Bryozoans Glaciation during the late Ordovician in Africa

PALEOZOIC LIFE Cambrian Explosion>Break up of Rodinia radiation of all phyla>Continental Shelves Cambrian Reef Systems Cambrian extinctions (2nd largest) Ordovician radiation Global Faunas (Cambrian vs. Paleozoic Faunas) Ordovician Reef Systems End-Ordovician extinction events

THE TOMMOTIAN FAUNA Small Shelly Fossils 1-2 mm Calcium phosphate Calcium cqarbonate Most phyla represented 1 to 2 MY duration

Trilobite Radiation Comprise 95% of all Cambrian Fossils Most successful arthropod Chitinous shell with an underlayer of calcite 5 major extinctions during the Cambrian and associated radiations Each Cambrian Biomere involved the extinction of 40 to 95% of existing trilobite genera

THE BURGESS SHALE Fine grained turbidite deposit at the base of a reef

THE BURGESS FAUNA Hallucigenia Anomalocaris Opabinia

Archaeocyathids & Stromatoporoid Reefs Archeocyathid Reefs begin during the Tommotian Stage in Siberia Spread rapidly through world Extinct by Early Cambrian Stromotoporoid Reefs begin during the Middle Cambrian They remain a dominant reef builder until the Devonian

Ordovician Life Terminal Cambrian trilobite extinction led the way for rapid Ordovician radiations in other groups Radiation of molluscs particularly gastropods decreased importance of stromatolites Tabulate and Rugose coral reefs Graptolites as index fossils Emergence of land plants First Vertebrates

Ordovician Extinctions Blackriver-Trenton Mid Ordovician, catastrophic regional extinction All echinoderms and cephalopods; 90% trilobites, 83% pelecypods Terminal Ordovician Extinction Major glaciation in Gondwana (sea level drop] 3rd largest in recorded geologic history; 80% of all genera

THE MIDDLE PALEOZOIC THE SILURIAN 438-408 MY SILURES>> WELSH TRIBE Roderick Murchison 1835 THE DEVONIAN 408-360 MY (Old Red Sandstone) DEVON>> County in SW England Roderick Murchison Adam Sedgwick 1839

INTRODUCTION Silurian Devonian 30 MY Duration Devonian 48 MY Duration Final Collision and Suturing of Baltica and Laurentia Caledonian and Arcadian Orogenies High Stands of Sea Level Epicontinental seas; marine deposits and thick sequences of evaporites Reefs became important

Paleogeography

PALEOGEOGRAPHY Closing of Iapetus Ocean Baltica-Laurentia; Mongolia-Siberia Closing of Rheic Ocean as Gondwana migrated to west (Laurentia/Baltica-Gondwana) Laurentia continued to be a tropical craton Shallow seas covered the continents during much of Silurian Devonian orogenies in Northern Hemisphere Caledonian (Scandinavia/Greenland) & Acadian (New England) & Antler (CA-NV)

Cratons and Mobile Belts of North America and Europe

TECTONIC EVENTS Caledonian & Acadian Orogenies Extension of Late Ordovician Taconic Orogeny Mid Devonian Iapetus Ocean closed Baltica collided with Laurentia Avalonia (Island Arc) sutured to both Baltica and Laurentia Norway collided Greenland forming the highlands responsible for the Old Red Sandstone

Orogenic Development Of the Eastern US Acadian Orogeny produced a thick clastic wedge (the Catskill Wedge) of red beds [conglomerates and sandstones]

East-West Cross Section across the Devonian Catskill Wedge During the Devonian the rate of sedimentation increased from 7m/MY to 17m/MY to 70m/MY Chattanooga Shale- Anoxic black shale, marker bed

Lithofacies & Thickness Map of the Upper Devonian Sequence of the Eastern US

The Appalachians Valley and Ridge Blue Ridge Province Inner Piedmont folded & faulted sedimentary rks Blue Ridge Province metamorphosed Precambrian and Paleozoic Rks Inner Piedmont high grade metamorphic rks intruded by granites Charlotte & Carolina Slate Belt metamorphosed & folded late Proterozoic & Cambrian sediments and volcanics

Physiographic Provinces of the Appalachian Region

Highland Areas Associated with the Antler Orogeny of California- Nevada

Domes and Basins Vertical Uplift and Subsidence Erosional and Depositional Features

Depositional Basins of the North American Craton

Model Illustrating the Deposition of Evaporites Michigan Basin Cyclic: Dolomite, Anhydrite, Halite 1500 m of carbonates, rock salt and gypsum in 5 major cycles

NEOPROTEROZOIC TO CENOZOIC TRANSGRESSIONS AND REGRESSIONS OBSERVED ON THE CRATON Variable sea level represented sequences of sediments bounded by unconformities on all of the cratons - Highest Stand of sea Level

Oriskany Sandstone Kaskaskia Transgression

The Reef System Tabulate corals and Stromotoporoid sponges Fauna was vertically zoned (tiered by depth) Clear ecological succession in reef building from pioneer community (clumps of twig-like colonies) to platy and domed shaped colonies to binding stage by sponges Michigan, Canning Basin (Australia), British Columbia

Mineral Deposits Sedimentary copper, lead and zinc sulfides and Iron ores Occur in shales and carbonates Disseminated or interbedded Tri-state mining district (MO) Howard’s Pass, Yukon, Canada Wales New York to Alabama

Clinton Iron Ore Silurian Clinton Group near Birmingham, AL The ore is an oolite of hematite (iron oxide)

Other Economic Deposits Silurian Salt, Michigan and upstate New York Silurian Petroleum Deposits-OH, OK,TX Devonian Petroleum Deposits Williston Basin- MT and Alberta First oil well in US 1859 (PA) Silica for glass- Devonian Oriskany Sandstone, 95-99.8% pure

Mid-Paleozoic Climates Gondwana centered over the South Pole climates ranged from cold to warm glacial striations present in South America yet Red beds and carbonates and evaporites were also present in N. Africa, India and Australia Other continents were equatorial Laurentia, Baltica and Siberia were warm

MID PALEOZOIC LIFE The Origin of the Ammonoids Cephalopods, Devonian Evolved from straight chambered nautiloids Eurypterids and the Origin of Arachnids Chelicerata (horseshoe crabs and sea scorpions) Ferocious predators of the Paleozoic seas

Life of the Silurian Eurypterids Devonian forms reached 2 m Huge eyes and pincers

Radiation of Fishes During Cambrian and Ordovician only 1 order of fish, jawless, Ostracoderms (Marine) Early Silurian 3 more orders of jawless fish and the first jawed fish, acanthodian, appeared and inhabited both marine and fresh water By Middle Devonian all classes of jawed fish had appeared All restricted to 40o of the equator Extinction at end of Devonian, terminated the ostracoderms and the armored placoderms

Evolution of the 5 Major Groups of Fishes

Ostracoderms A: Thelodus B: Pteraspis C: Jamoytius D: Hemicyclaspis

Evolution of Jaws in Fish

Placoderms Skull 1 m high fish 10m long Dunkleosteus

The Origin of Tetrapods Amphibian Crossopterygians

Ichthyostega Late Devonian (Old Red Sandstone) One of the Oldest Known Amphibians

The Radiation of Land Plants Earliest Fungi appear in the Early Silurian First Land Plants are Late Ordovician First Vascular Plants are Late Silurian With the appearance of forests in Late Devonian oxygen levels increased and reached a peak in the Late Paleozoic Land erosion rates significantly decreased

The Development of Tiering Vertical Separation Between Organisms Removes competition between organisms of similar feeding habits Different stalk heights in crinoids Low herbaceous plants grading into true forest with tall trees

Terrestrial Communities By Early Devonian land communities were diverse Rhynie Chert (Aberdeen, Scotland) Silicified peat bog Preserved plants as well as spiders, mites and insects

Mass Extinction Major marine extinction of the Late Devonian Frasnian-Famennian epochs 33% marine families became extinct Nearshore marine and reef benthic species corals, stromotoporoids, all but 1 order of trilobites, many brachiopods and ammonoids No corresponding terrestrial extinction

Frasnian-Famennian Extinction Occurred during a regression Associated with low oxygenated water and high metal concentrations Sharp drop in temperature (O2-Isotope studies) Presence of glass spherules All indicate a probable asteroid impact which caused deep anoxic and high metallic content water to poison shoal communities