StratigraphyStratigraphy DEFINITION OF STRATIGRAPHYDEFINITION OF STRATIGRAPHY 1. Branch of geology that deals with definition & 1. Branch of geology that deals with definition &

description of major & minor natural division of description of major & minor natural division of rocks... w/ the interpretation of their significance rocks... w/ the interpretation of their significance in geologic history.in geologic history.

2. Specifically, the geologic study of the form, 2. Specifically, the geologic study of the form, arrangement, geographic distribution, arrangement, geographic distribution, chronological succession, classification & esp. chronological succession, classification & esp. correlation and mutual relationships of rock strata correlation and mutual relationships of rock strata in normal sequence.in normal sequence.

3. It involves interpretation of these features of 3. It involves interpretation of these features of rock strata in terms of origin, occurrence, rock strata in terms of origin, occurrence, environment, thickness, lithology, composition, environment, thickness, lithology, composition, fossil content, age, history, paleogeography etcfossil content, age, history, paleogeography etc

http://web.wm.edu/geology/virginia/provinces/Blueridge/blue_ridge_strat.html?svr=wwwhttp://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch11/ch_11_f.html

IntroductionIntroduction

A.A. Beginning-Beginning-(~1500AD) da (~1500AD) da Vinci saw fossils in Vinci saw fossils in rks of Italian rks of Italian ApenninesApennines

• Concluded fossils Concluded fossils once living marine once living marine organismsorganisms

http://www.ucmp.berkeley.edu/history/vinci.htm

IntroductionIntroduction

B.B. Steno- 1669-Steno- 1669-important important contributorcontributor

• Principle of Principle of Original Original HorizontalityHorizontality

• Principle of Principle of SuperpositionSuperposition

• Principle of Lateral Principle of Lateral ContinuityContinuity

http://www.ucmp.berkeley.edu/history/steno.html

Steno PrinciplesSteno Principles

Lateral ContinuityLateral Continuity

Superposition

Original Horizontality

http://itc.gsw.edu/faculty/bcarter/histgeol/time/latcont.htm

Development of Sed Strat as Development of Sed Strat as ScienceScience

• Organization of Organization of sed rocks—sed rocks—Arduino (1714-15) Arduino (1714-15) divided rocksdivided rocks

• Primary Mtns-Primary Mtns-metallic ores no metallic ores no fossilsfossils

• Secondary Mtns-Secondary Mtns-Stratified, Stratified, lithified, lithified, fossiliferous, no fossiliferous, no fossilsfossils

• Tertiary low Tertiary low Mtns- Mtns- Fossiliferous, Fossiliferous, unconsolidated unconsolidated gravels, sands gravels, sands clay, volcanicsclay, volcanics

• Alluvium- Alluvium- Sediment Sediment washed down washed down from mtnsfrom mtns

http://www.quaternary.stratigraphy.org.uk/about/history.html

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science• Geologic Cycle and Geologic Cycle and

UniformitarianismUniformitarianism• James Hutton James Hutton

(1727-1797)-(1727-1797)-Scottish Physician, Scottish Physician, farmerfarmer

Noted cyclicity Noted cyclicity to earth’s to earth’s behaviorbehavior

Uplift, erosion, Uplift, erosion, transport, transport, depositiondeposition

Established Established Principle of Principle of Uniformitarianism Uniformitarianism or Actualismor Actualism

present key to present key to past but rates past but rates change and change and catastrophes catastrophes occuroccur

http://www.ucmp.berkeley.edu/history/hutton.htm

Development of Sed Strat as Development of Sed Strat as Science Science

– Birth of Biostratigraphy Birth of Biostratigraphy & Stratigraphic & Stratigraphic CorrelationCorrelation

• William Smith(1769-1839)-William Smith(1769-1839)-English surveyor, engineerEnglish surveyor, engineer

““father” of biostratigraphyfather” of biostratigraphy Canal builder noted Canal builder noted

relationship of fossils & rocksrelationship of fossils & rocks Established law of faunal Established law of faunal

succession—fossils succeed succession—fossils succeed each other in organized & each other in organized & recognizable fashionrecognizable fashion

Produced first geologic mapProduced first geologic map

gsahist.org

Birth of Biostratigraphy & Stratigraphic CorrelationBirth of Biostratigraphy & Stratigraphic Correlation

D’Orbigny D’Orbigny (1842)-developed (1842)-developed biologic stage for biologic stage for rock divisionrock division strata strata systematically systematically follow each other follow each other with with characteristic characteristic fossil assemblagefossil assemblage

Oppel (1856)- Oppel (1856)- developed developed biologic zonebiologic zone Rocks deposited Rocks deposited during existence during existence of specific fossilof specific fossil

Zones based of Zones based of first appearance first appearance of last of last appearance of appearance of organismsorganisms

Zones could be Zones could be correlatedcorrelated

Oppel ZonesOppel Zones

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science

• Petrographic Petrographic microscope microscope developmentdevelopment

• Sorby began microscopic Sorby began microscopic study of rocksstudy of rocks

• Led to description and Led to description and systematic study of rockssystematic study of rocks

• Geologic Revolution-Geologic Revolution-Seafloor Spreading and Seafloor Spreading and Plate TectonicsPlate Tectonics

• 1950-1960s- 1950-1960s- Renaissance periodRenaissance period

• More funds, more More funds, more geophysical exploration, geophysical exploration, Deep Sea Drilling ProjectDeep Sea Drilling Project

• More oil exploration More oil exploration

New ToolsNew Tools Magnetic and Seismic Magnetic and Seismic

SurveyingSurveying Identification of Identification of

normal/reverse normal/reverse periods led to periods led to magnetostratigraphmagnetostratigraphyy

Seismic surveying Seismic surveying could identify units could identify units and unconformities, and unconformities, packages of related packages of related rocksrocks

Isotope stratigraphyIsotope stratigraphy Use carbon and Use carbon and

oxygen isotopes to oxygen isotopes to correlatecorrelate units units

petroleum-gas.blogspot.com

http://www2.ocean.washington.edu/oc540/lec01-28

MagnetostratigraphyMagnetostratigraphy

sp.lyellcollection.org

Seismic StratigraphySeismic Stratigraphy

www-odp.tamu.edu

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science

• Sedimentary Sedimentary Rocks and Rocks and Earth HistoryEarth History

• PaleoclimatePaleoclimate study of study of

ancient ancient climate climate

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science

• Sedimentary Sedimentary Rocks and Rocks and Earth HistoryEarth History

• PaleogeograpPaleogeographyhy reconstructioreconstructio

n of area for n of area for given time in given time in past past

Wiley.com

http://jan.ucc.nau.edu/~rcb7

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science

• Sedimentary Sedimentary Rocks and Rocks and Earth HistoryEarth History

• Paleoecology Paleoecology & Evolution& Evolution studies studies

relationships relationships between between ancient ancient organisms & organisms & their their environmentenvironmentss

http://scienceblogs.com/laelaps/Futalognkosaurus%2Bmural.jpg

Development of Sed Strat as ScienceDevelopment of Sed Strat as Science

• Sedimentary Sedimentary Rocks and Earth Rocks and Earth HistoryHistory

• PaleoceanographPaleoceanography & Ancient y & Ancient AtmosphereAtmosphere Composition of Composition of

ancient oceans ancient oceans and atmosphere and atmosphere using isotopes using isotopes

http://www.jamstec.go.jp/rigc/j/ebcrp/paleo/