Sedimentary Geology Geos 240 – Chapter 5 The Principles of Stratigraphy Dr. Tark Hamilton Camosun...

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Sedimentary Sedimentary GeologyGeology

Geos 240 – Chapter Geos 240 – Chapter 55

The Principles of The Principles of StratigraphyStratigraphy

Dr. Tark HamiltonDr. Tark Hamilton

Camosun CollegeCamosun College

Correlation of Correlation of StratigraphyStratigraphy

This mainly works for bedded Sedimentary rocksThis mainly works for bedded Sedimentary rocks Correlation of rocks, beds, successions, fossilsCorrelation of rocks, beds, successions, fossils Lithology: LithostratigraphyLithology: Lithostratigraphy Biostratigraphy: widespread but short lived Biostratigraphy: widespread but short lived

fossilsfossils Chronostratigraphy: zircons, igneous Chronostratigraphy: zircons, igneous

tephra/dyketephra/dyke Allostratigraphy: unconformity bounded Allostratigraphy: unconformity bounded

packagespackages Sequence Stratigraphy: cycles, eustatic, geneticSequence Stratigraphy: cycles, eustatic, genetic

Stratigraphy ofStratigraphy ofNorthern Ellesmere Island, Northern Ellesmere Island,

NunavutNunavutAtlantic Opens

Ab

saro

ka S

eri

es

Kask

ask

ia S

eri

es

Iapetus Closes(Missing Permian)

Bayou-Delta FaciesGivetian to Fammenian: Tiktaalik

Origins of Stratigraphy: Origins of Stratigraphy: Founders IFounders I

~1550CE Leonardo da Vinci:~1550CE Leonardo da Vinci: Tethyan marine Tethyan marine fossils in Italian alpsfossils in Italian alps

1669 CE Nicolaus Steno:1669 CE Nicolaus Steno: Original Original Horizontality, Superposition (younger on top of Horizontality, Superposition (younger on top of older beds)older beds)

~1750 CE James Hutton:~1750 CE James Hutton: Uniformitarianism Uniformitarianism (gradualism), Geological cycles (uplift/tilting, (gradualism), Geological cycles (uplift/tilting, erosion. Sedimentation) & Deep Geological erosion. Sedimentation) & Deep Geological TimeTime

~1815 CE William Smith:~1815 CE William Smith: Principle of Faunal Principle of Faunal Succession, one of earliest Geological maps, Succession, one of earliest Geological maps, Strata of England and WalesStrata of England and Wales

Origins of Stratigraphy: Origins of Stratigraphy: Founders IIFounders II

~1842 Alcide d’ Orbigny:~1842 Alcide d’ Orbigny: Biological stages 10 – 100 Biological stages 10 – 100 Ma, evolution based assemblages. Crude Ma, evolution based assemblages. Crude biostratigraphy.biostratigraphy.

~1856 Albert Oppel:~1856 Albert Oppel: Biologic zones = range of a Biologic zones = range of a specific organism, higher resolution biostratigraphy.specific organism, higher resolution biostratigraphy.

~1917 Joseph Barrell:~1917 Joseph Barrell: Base level or sea level Base level or sea level changes will result in breaks (unconformities) genetic changes will result in breaks (unconformities) genetic strat.strat.

1963 Larry Sloss:1963 Larry Sloss: Subaerial unconformities bound Subaerial unconformities bound stratigraphic sequences. Allostratigraphystratigraphic sequences. Allostratigraphy

~1960’s Harry Wheeler:~1960’s Harry Wheeler: Time distance diagrams: Time distance diagrams: duration, extent and hiatus in strat. Sequencesduration, extent and hiatus in strat. Sequences

1977 Peter Vail:1977 Peter Vail: Global Eustatic Sea Level changes Global Eustatic Sea Level changes & Global correlations on seismic strat. Who needs & Global correlations on seismic strat. Who needs biostrat, local basins?biostrat, local basins?

William “Strata” Smith: 1769-1839

Principal of Principal of Stratigraphic Stratigraphic Association of Association of Fossils (faunal Fossils (faunal succession)succession)

1815 11815 1stst Geological Geological Map of EnglandMap of England

Canal SurveyorCanal Surveyor 11stst Wollaston Wollaston

Medalist of the Medalist of the Geological Society Geological Society of Londonof London

Cross Section of London Cross Section of London BasinBasin

Jerome Harrison, 1882Jerome Harrison, 1882

Following in the footsteps of William “Strata” Smith

Correlation of StratigraphyCorrelation of Stratigraphy Comparing & connecting stratigraphic Comparing & connecting stratigraphic

successions between localities: trenches, successions between localities: trenches, cliffs, boreholes or across and between cliffs, boreholes or across and between basinsbasins

Lithology: LithostratigraphyLithology: Lithostratigraphy, Original , Original Triassic, 3 distinctive beds across the Alps. Triassic, 3 distinctive beds across the Alps. (Alberti’s Trias referred to the division of (Alberti’s Trias referred to the division of these strata into three units: the Bunter these strata into three units: the Bunter [or Buntsandstein], Muschelkalk (Limes), [or Buntsandstein], Muschelkalk (Limes), and Keuper (Marls), known as the and Keuper (Marls), known as the “Germanic facies,” is mainly Continental. “Germanic facies,” is mainly Continental. The type sections are now more widespread The type sections are now more widespread Marine facies based on ammonoids.Marine facies based on ammonoids.

Muschelkalk-Keuper Muschelkalk-Keuper Boundary:Boundary:

Winterswijk Netherlands: H.W. Winterswijk Netherlands: H.W. Oosterink et al 2006Oosterink et al 2006

Marls/Black ClaysRhaetian/Liassic

MuschelkalkLimestones

(BuntsandsteinUnexposed)

Correlation of Correlation of StratigraphyStratigraphy

Biostratigraphy: widespread but short lived Biostratigraphy: widespread but short lived fossilsfossils Relative ages requires statistical numbers of fossilsRelative ages requires statistical numbers of fossils Only good to +/- 1Ma (the average species lifespan)Only good to +/- 1Ma (the average species lifespan)

ChronostratigraphyChronostratigraphy Absolute radiometric dates from: zircons, apatites, Absolute radiometric dates from: zircons, apatites,

igneous events, tephra-ash beds, U-Pb or igneous events, tephra-ash beds, U-Pb or 3939Ar/Ar/4040Ar Ar Magnetic Reversal Stratigraphy ≤ CretaceousMagnetic Reversal Stratigraphy ≤ Cretaceous Marine Stable Isotope: H/D, Marine Stable Isotope: H/D, 1616O/O/1818O, O, 3232S/S/3434S, S, 1212C/C/1313C C

Allostratigraphy: unconformity bounded Allostratigraphy: unconformity bounded packagespackages

Sequence Stratigraphy: cycles, eustatic, geneticSequence Stratigraphy: cycles, eustatic, genetic

1800’s Faunal Succession & 1800’s Faunal Succession & Correlation: Stephanoceras and Correlation: Stephanoceras and

Micraster Micraster Lower Jurassic (Midlands) & Upper Lower Jurassic (Midlands) & Upper

Cretaceous ChalkCretaceous ChalkAmmonite (Cephalopoda) & Echinoid (Heart Urchin, Ammonite (Cephalopoda) & Echinoid (Heart Urchin,

Echinodermata)Echinodermata)

BiostratigraphyBiostratigraphy

Dozens to hundreds of speciesDozens to hundreds of species Gradual structural changes Gradual structural changes evolution evolution Biozones (time), Stages (evolutionary Biozones (time), Stages (evolutionary

differentiation)differentiation) Picky species nail the environment, quiet, rough, Picky species nail the environment, quiet, rough,

O2O2 FAD: First occurrence datumFAD: First occurrence datum Coincident Range (Concurrent species)Coincident Range (Concurrent species) LAD: Last Occurrence DatumLAD: Last Occurrence Datum Biocenose assemblages (living ecologies)Biocenose assemblages (living ecologies) Thanatocenose assemblages (enviro-accumulations)Thanatocenose assemblages (enviro-accumulations)

ChronostratigraphyChronostratigraphy Post WWII, Harold Urey, U.Chicago, Solid Post WWII, Harold Urey, U.Chicago, Solid

Source Mass Specs, Source Mass Specs, 238238U U 206206Pb, Pb, 8787Rb Rb 8787Sr Sr & & 8787Sr/ Sr/ 8686Sr, Deuterium, Precambrian Sr, Deuterium, Precambrian Atmosphere, Nobel PrizeAtmosphere, Nobel Prize

Thermochronometry, Derek York U of T : Thermochronometry, Derek York U of T : Lunar rocks, Ar-39/40, thermal blocking Lunar rocks, Ar-39/40, thermal blocking temperaturestemperatures

Chronostratigraphy: Radio-Chronostratigraphy: Radio-isotopesisotopes

U/Pb clocks from Zircon & Baddeleyite for U/Pb clocks from Zircon & Baddeleyite for Precambrian sediments, igneous cores & meta Precambrian sediments, igneous cores & meta rimsrims

Rb/Sr for intercalated Volcanics or feldspars for Rb/Sr for intercalated Volcanics or feldspars for Mesozoic and older rocks (due to long half life Mesozoic and older rocks (due to long half life and low Rb/Sr ratio)and low Rb/Sr ratio)

K/Ar for Pliocene and older VolcanicsK/Ar for Pliocene and older Volcanics 39/40Ar some sedimentary minerals like 39/40Ar some sedimentary minerals like

Glauconite or Fission Track for Pleistocene and Glauconite or Fission Track for Pleistocene and older Volcanicsolder Volcanics

Disequilibrium Uranium series isotopes (Ra for Disequilibrium Uranium series isotopes (Ra for Ca) for Pleistocene & older Carbonates, reefs, Ca) for Pleistocene & older Carbonates, reefs, speleothemsspeleothems

Radioactive fallout correlation dating: Radioactive fallout correlation dating: 137137Cs, Cs, 9090SrSr

Allostratigraphy (Larry Allostratigraphy (Larry Sloss, 1963)Sloss, 1963)

Major Unconformities bound packages of Major Unconformities bound packages of stratigraphy which correlate across and stratigraphy which correlate across and between continentsbetween continents

Caused by tectonic and global eustatic Caused by tectonic and global eustatic events, 10-100 Ma long for North America:events, 10-100 Ma long for North America: ZuniZuni AbsarokaAbsaroka KaskaskiaKaskaskia TippecanoeTippecanoe SaukSauk

Later Peter Vail of Exxon extended this to the Atlantic Later Peter Vail of Exxon extended this to the Atlantic Basin mainly on eustatics alone & Seismic Sequence Basin mainly on eustatics alone & Seismic Sequence StratigraphyStratigraphy

Stratigraphic Variability for a Stratigraphic Variability for a Hypothetical LithostratigraphyHypothetical Lithostratigraphy

Relative Datumflattened

Shale line to right edge

Log Shape Analysis:

Wiggle Matching

SP or Resistivity

2 Methods of Defining 2 Methods of Defining StratigraphyStratigraphy

A) Nothing Happened or B) Widespread Distinctive Event

Ordovician Cambrian

Maastrictian (Cretaceous)

Paleocene (Tertiary)

Cow Head Breccia: Green Point Newfoundland K/T Boundary Clay, Frenchman Valley, Saskatchewan

Kaskaskia

Absaroka

Tippecanoe

Sauk

Zuni

Allostratigraphic Breaks in Allostratigraphic Breaks in Rift BasinRift Basin

Formations are Formations are LithostratigraphicLithostratigraphic

Subdivision of Regional Subdivision of Regional Cambro-Ordovician Strata: by Cambro-Ordovician Strata: by

Litho & Allostrat.Litho & Allostrat.

Tippecanoe is Upper Ordovician – Silurian overSauk = Upper Cambrian – Middle Ordovician

Biozones

Biozones: Maastrichtian Chalk Biozones: Maastrichtian Chalk NW EuropeNW Europe

# = Species

Concurrent RangeBiozones