Time Scales Time Perspectives Chronostratigraphy Geologic Time Scale
- Slides: 45
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Time Perspectives Catastrophism http: //www. meteorcrater. com/
Time Perspectives Uniformitarianism
Time Perspectives How Much is a Billion? save $100 / day ? how may years to save 1 billion $
Time Scales The Geologic Time Scale: an arrangement of the earth’s geologic record into a standard sequence of units. • relative age order • boundaries based on fossils, lithology, polarity • absolute ages by radiometric dating
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Chronostratigraphy: establish time relationships among rock units Geologic Time Units • Geochronologic Units - time interval • Chronostratigraphic Units - rock body representative of time interval
Chronostratigraphy Geochronologic Unit – time interval Eon Era *Period Epoch Age Chron
Chronostratigraphy Geochronologic Unit – time interval Eon – Phanerozoic Era – Mesozoic *Period – Cretaceous Epoch – Late Cretaceous Age – Campanian Chron – Orbitoides tissoti
Chronostratigraphy Chronostratigraphic Unit – rock bodies representative of time interval Eonothem Erathem *System Series Stage Chronozone
Chronostratigraphy Chronostratigraphic Unit – rock bodies representative of time interval Eonothem Erathem *System – Cretaceous System Series – Upper Cretaceous Series Stage Chronozone
Chronostratigraphy System Subdivisions Period Subdivisions Lower and Upper Early and Late
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Geologic Time Scale
(Harland et al. , 1990)
Maastrichtian Geologic Time Scale Even More Detail… Ages of Cretaceous Period Campanian Santonian Coniacian Turonian Cenomanian Albian Aptian Barremain Hauterivian Valanginian Ryazanian
Geologic Time Scale millions of years ago Precambrian Events after (http: //www. ucmp. berkeley. edu/precambrian. html)
Geologic Time Scale 3. 8 4. 0 3. 5 -3. 7 3. 5 3. 6 4. 4 World’s Oldest Rocks (Age in Billion Years)
Geologic Time Scale millions of years ago Precambrian Events after (http: //www. ucmp. berkeley. edu/precambrian. html) www. calm. wa. gov. au/national_parks/hamelin_pool_mnr. html
Geologic Time Scale millions of years ago Precambrian Events after (http: //www. ucmp. berkeley. edu/precambrian. html) http: //www-rohan. sdsu. edu/~rhmiller/depositionfeatures 1/
Geologic Time Scale millions of years ago Precambrian Events after (http: //www. ucmp. berkeley. edu/precambrian. html) http: //www. ucmp. berkeley. edu/vendian/pter. gif
Geologic Time Scale Amphibians Land Plants Animals with Hard Parts http: //www. inhandmuseum. com/images/Geologic_Timeline. GIF http: //palaeo. gly. bris. ac. uk/Palaeofiles/Lagerstatten/Burgess/gallery. html
Primates Break-up of Pangea Dinosaurs Amphibians Land Plants Animals with Hard Parts http: //www. inhandmuseum. com/images/Geologic_Timeline. GIF
Human Civilizations Ice Ages Grasses Primates Break-up of Pangea Dinosaurs Amphibians Land Plants Animals with Hard Parts http: //www. inhandmuseum. com/images/Geologic_Timeline. GIF
Relative Time Absolute Ages
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Radioactive Decay radioactive radiogenic Parent Daughter • loss of particle from nucleus • statistical behavior of population • constant decay rate
Radioactive Decay Some Types of Radioactive Decay Beta Decay: N P and lose e- Alpha Decay: lose 2 P + 2 N AGI, 1999
Radioactive Decay 87 Rb 87 Sr
Radioactive Decay Half Life: The time required for half of the amount of parent to decay to daughter “Close the Box” Time Atoms Parent Atoms Daughter “Close the Box” 6 0 1 Half Life 3 3
Radioactive Decay M&M Experiment Number of Parents 100 80 60 40 20 0 0 1 2 Number of Half Lives 3 4
Radioactive Decay
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Radiometric Dating Parent-Daughter Pairs Parent Daughter Half-Life (y) Age Ranges Material 238 U 206 Pb 4. 5 billion < 65 million zircon 235 U 207 Pb 704 million > 60 million zircon 87 Rb 87 Sr 49 billion > 5 million micas, K-spar 40 K 40 Ar 1. 3 billion > 100, 000 micas 14 C 14 N 5, 730 < 40, 000 organics, calcite
Radiometric Dating Analytical Methods isolate parent and daughter measure amount of parent and daughter
Radiometric Dating What event are you dating? volcano 2_und_nodak_edu NPS
Radiometric Dating Considerations • choose right mineral • assume a closed system zircon
Radiometric Dating 14 C-dating Concerns variable production rates of 14 C old C in oceans selective uptake of 14 C
Radiometric Dating absolute date Calibrate the Time Scale relative age biozone absolute date relative age biozone http: //www. talkorigins. org/faqs/dating. html
Radiometric Dating Assign ages to relative time period boundaries USGS
Time Scales • Time Perspectives • Chronostratigraphy • Geologic Time Scale • Radioactive Decay • Radiometric Dating • Pilot Knob Lab Text: Manual, p. 3, 29, 131 -136; Boggs, Ch. 18
Pilot Knob Lab • basalt • pyroclastics
Pilot Knob Lab
Pilot Knob Lab Kavachi, Solomon Islands NOOA
- Compare geologic time with the geologic column.
- How is the geologic time scale organized
- Earth's history and geologic time graphic organizer
- How is the geologic time scale organized
- Geologic time scale animals
- Geologic time scale drawing
- Geologic time scale drawing
- Nooa
- Geologic time scale
- Silurian period
- Geologic time scale
- 4 zoic eras
- Fossils
- Geological time scale graphic organizer
- Eon division
- Time scale
- What is the longest subdivision in geologic time
- Chapter 12 geologic time
- Caprock
- Geologic history meaning
- Geologic column definition
- Geologic history of texas
- Principle of original horizontality
- Geologic history
- Geologic features
- Geologic layers of earth
- California geologic energy management division
- Scale definition geography
- A proportional two-dimensional drawing of an object
- It is a five tone scale
- Definition of map scale
- Large scale vs small scale map
- Introduction to topographic maps
- Large scale vs small scale map
- Scale up vs scale out
- Scale up and scale out in hadoop
- Scale drawings/models & scale factor
- Construct a diagonal scale of rf 1/4000
- 7-7 scale drawings and models
- Poss level
- Scale out architecture in big data analytics
- Inner scale and outer scale
- Outer scale protractor
- A plain scale of 1 cm=5m and show on it 37m
- Mussolini death
- Strategic perspective of pay