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