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Early Paleozoic Earth Early Paleozoic Earth HistoryHistory

William SmithWilliam Smith

First geologic mapFirst geologic mapStudied the early Paleozoic Rocks of EnglandStudied the early Paleozoic Rocks of EnglandCoal Mines and CanalsCoal Mines and CanalsLaw of Faunal SuccessionLaw of Faunal Succession

William Smith 1769 –1839)

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William SmithWilliam Smith’’s Maps Map

Breakup of Breakup of PannotiaPannotia

By the beginning of the Paleozoic, six major By the beginning of the Paleozoic, six major continents:continents:

LaurentiaLaurentiaBalticaBalticaSiberiaSiberiaChinaChinaKazakhstaniaKazakhstaniaGondwanaGondwana

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CratonsCratons and Mobile Beltsand Mobile Belts

The supercontinent began breaking apart The supercontinent began breaking apart sometime during the latest Proterozoicsometime during the latest ProterozoicBy the beginning of the Paleozoic Era, six major By the beginning of the Paleozoic Era, six major continents were presentcontinents were presentEach continent can be divided into two major Each continent can be divided into two major components components

a craton a craton and one or more mobile beltsand one or more mobile belts

Composition of Paleozoic ContinentsComposition of Paleozoic Continents

CratonsCratonsRelatively stable and immobile parts of continentsRelatively stable and immobile parts of continentsForm the foundation for sedimentationForm the foundation for sedimentationConsist of two partsConsist of two parts

Shield Shield –– exposed portion of igneous and metamorphic rocks of the exposed portion of igneous and metamorphic rocks of the PrecambrianPrecambrianPlatform Platform –– buried, extending outward from shieldburied, extending outward from shield

Mostly flat but some parts gently folded into domes and basinsMostly flat but some parts gently folded into domes and basins

Mobile BeltsMobile BeltsElongated areas of mountain building from plate Elongated areas of mountain building from plate convergenceconvergence

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Paleozoic Paleozoic PaleogeographyPaleogeography

Early Paleozoic Early Paleozoic -- CambrianCambrianThe six continents were dispersed in low latitudesThe six continents were dispersed in low latitudesNo polar iceNo polar iceEpeiricEpeiric seas on all platformsseas on all platformsHighlands on Highlands on GondwanaGondwana, eastern Siberia, central , eastern Siberia, central KazakhstaniaKazakhstania

EpeiricEpeiric SeasSeas

Widespread shallow seas that transgressed and Widespread shallow seas that transgressed and regressed across the platformregressed across the platformChanges in sea level caused transChanges in sea level caused trans-- and and regressionsregressions

GlaciationGlaciationPlate movement/spreading ratePlate movement/spreading rate

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Paleozoic Paleozoic PaleogeographyPaleogeography

Late CambrianLate Cambrian

Water circulated freely among ocean basins, and the Water circulated freely among ocean basins, and the polar regions were mostly ice freepolar regions were mostly ice free

By the Late Cambrian,By the Late Cambrian, epeiricepeiric seas had covered areas seas had covered areas of of LaurentiaLaurentia, , BalticaBaltica, Siberia, , Siberia, KazakhstaniaKazakhstania, China, China

Highlands were present in northeastern Highlands were present in northeastern GondwanaGondwana, eastern Siberia, and central , eastern Siberia, and central KazakhstaniaKazakhstania

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Late CambrianLate Cambrian

Late OrdovicianLate Ordovician

Plate movements played a major role in the changing Plate movements played a major role in the changing global geography global geography

Gondwana moved southward during the Ordovician and Gondwana moved southward during the Ordovician and began to cross the South Polebegan to cross the South Pole

AvaloniaAvalonia separated from separated from GondwanaGondwana and collided with and collided with BalticaBaltica

An active convergent plate boundary existed along its An active convergent plate boundary existed along its eastern margin during the Ordovicianeastern margin during the Ordovician

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Late OrdovicianLate Ordovician

Middle SilurianMiddle Silurian

BalticaBaltica, with attached , with attached AvaloniaAvalonia, moved northwestward relative to , moved northwestward relative to Laurentia and collided with it to form the larger continent of Laurentia and collided with it to form the larger continent of LaurasiaLaurasia

This collision, which closed the northern Iapetus Ocean, is This collision, which closed the northern Iapetus Ocean, is marked by the Caledonian marked by the Caledonian orogenyorogeny

The southern part of the Iapetus Ocean still remained open The southern part of the Iapetus Ocean still remained open between Laurentia and Gondwana between Laurentia and Gondwana

Siberia and Kazakhstania moved from a southern equatorial Siberia and Kazakhstania moved from a southern equatorial position during the Cambrian to north temperate latitudes by theposition during the Cambrian to north temperate latitudes by theend of the Silurian Periodend of the Silurian Period

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Middle SilurianMiddle Silurian

CratonicCratonic SequencesSequences

Large scale Large scale lithostratgraphiclithostratgraphic units representing units representing major major transgressivetransgressive and regressive cycles and regressive cycles bounded by unconformitiesbounded by unconformitiesCorrelatableCorrelatable across continents, basins and across continents, basins and mountain mobile beltsmountain mobile beltsRepresent sea level changes due to major Represent sea level changes due to major tectonic and/or glacial eventstectonic and/or glacial events

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Sequence Sequence StratigraphyStratigraphy

Allows for high resolution analysis of time and Allows for high resolution analysis of time and faciesfacies relationships in sedimentary rocksrelationships in sedimentary rocksStudy of rock relationships within timeStudy of rock relationships within time--stratigraphicstratigraphic framework of related framework of related faciesfaciesbounded by unconformities.bounded by unconformities.Sequence is the succession of rocks; boundaries Sequence is the succession of rocks; boundaries are the unconformities caused by regressionare the unconformities caused by regression

Evolution of North AmericaEvolution of North America

CratonicCratonicsequencesequence

Sequence Sequence stratigraphystratigraphy

Sauk Sauk SequenceSequence

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The Sauk SequenceThe Sauk Sequence

First major transgression onto the N. American First major transgression onto the N. American cratoncratonEarly Cambrian Early Cambrian –– shelfalshelfal sedimentation onlysedimentation onlyMiddle Cambrian Middle Cambrian ––epeiricepeiric seas transgress over seas transgress over the the cratoncratonLate Cambrian Late Cambrian –– epeiricepeiric seas cover most of N. seas cover most of N. America (except some shield and America (except some shield and transcontinental arch)transcontinental arch)

Early Paleozoic Evolution of North Early Paleozoic Evolution of North AmericaAmerica

TransTrans--continental continental ArchArch

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The Cambrian of the Grand Canyon The Cambrian of the Grand Canyon RegionRegion

The Cambrian of the Grand Canyon The Cambrian of the Grand Canyon RegionRegion

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The Grand Canyon: A The Grand Canyon: A TransgressiveTransgressiveFaciesFacies ModelModel

Cambrian Cambrian Rocks of the Rocks of the Grand CanyonGrand Canyon

Time Time TransgressiveTransgressive FormationsFormations

TimeLines

Faunal analysis of the Bright Angel Shale indicates that it is Early Cambrian in age in California

and Middle Cambrian in the Grand Canyon region.

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TimeTime--TrangressiveTrangressive Cambrian Cambrian FaciesFacies

Appalachian Appalachian Mobile BeltMobile Belt

Tippecanoe SequenceTippecanoe Sequence

Sauk Sea regressed exposing huge areas of Sauk Sea regressed exposing huge areas of carbonate to erosion = unconformitycarbonate to erosion = unconformityTransgression deposited The Tippecanoe Transgression deposited The Tippecanoe Sequence during OrdovicianSequence during OrdovicianWidespread pure quartz sandstone (St. Peter SS) Widespread pure quartz sandstone (St. Peter SS) with purity due to with purity due to resedimentationresedimentation of Sauk of Sauk sequence sandstonessequence sandstones

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Tippecanoe SequenceTippecanoe Sequence

Basal sandstones followed by extensive Basal sandstones followed by extensive fossiliferousfossiliferous carbonatescarbonatesOutboard of carbonate reefs are Outboard of carbonate reefs are shalesshales from from erosion of Taconic Highlands and erosion of Taconic Highlands and AppalacianAppalacianmobile beltmobile belt

Tippecanoe SequenceTippecanoe Sequence

TippecanoeTippecanoeSequenceSequence

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Transgressing Tippecanoe SeaTransgressing Tippecanoe Sea

Modern reef settingModern reef setting

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Cambrian Archeocyathid reef

Ordovician Bryozoan reef debris

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Stromatoporoids reef builders

Ordovician North American barrier reefs

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Ordovician reef outcrops

Ordovician Life

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EvaporitesEvaporites

Halite and Anhydrite deposits of early PaleozoicHalite and Anhydrite deposits of early PaleozoicLagoons behind barrier reefsLagoons behind barrier reefsMichigan basin Michigan basin –– limited circulationlimited circulation

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Halite from Evaporite deposits, Michigan Basin

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•Northern Michigan Basin sediments during the Silurian Period

End of the Tippecanoe SequenceEnd of the Tippecanoe Sequence

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Appalachian Mobile Belt and Appalachian Mobile Belt and Tectonic Tectonic OrogenyOrogeny

QueenstoneQueenstone Delta Delta ClasticClastic WedgeWedge

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