Earth History Dating geologic events like volcanic eruptions

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Earth History Dating geologic events like volcanic eruptions, uplift, subsidence, deposition, impacts, intrusion, ice

Earth History Dating geologic events like volcanic eruptions, uplift, subsidence, deposition, impacts, intrusion, ice ages, etc

Geologic Age Dating • Relative Age Dating – Places events in a sequence –

Geologic Age Dating • Relative Age Dating – Places events in a sequence – Only indicates one is older than other • Absolute Age Dating – Also called: Radiometric/Radio- active Dating – Identifies actual age

Relative Age Dating rules/laws to follow when dating rocks • • • Uniformitarianism Law

Relative Age Dating rules/laws to follow when dating rocks • • • Uniformitarianism Law of Original Horizontality Law of Superposition Law of Cross-cutting Relationships Law of Include Fragments Unconformities

Relative Age Dating • Uniformitarianism – “The present is the key to the past”

Relative Age Dating • Uniformitarianism – “The present is the key to the past” James Hutton – Geologic events are not catastrophic

Relative Age Dating • Original Horizontality – sedimentary rocks form horizontal to the surface

Relative Age Dating • Original Horizontality – sedimentary rocks form horizontal to the surface of the earth. – Sedimentary rocks usually form below sealevel

SEDIMENTARY ROCKS 75% of the Earth’s surface –sed Usually form below sea level form

SEDIMENTARY ROCKS 75% of the Earth’s surface –sed Usually form below sea level form from the compaction and cementation of sediments (lithification) Weathering (breakdown of rock) Sediment (fragments of rock) Erosion (movement/transport of sediment) Deposition (settling of sediment) Burial Compaction (pushing together of sediment Cementation (gluing of sediments) http: //www. westhamptonbeach. k 12. ny. us/Teachers/cohen/sciweb/earthscience/powerpoint_notes. htm

Properties of Sedimentary Rocks • • Layers/Strata Fragments of other rocks Fossils – remains/impression

Properties of Sedimentary Rocks • • Layers/Strata Fragments of other rocks Fossils – remains/impression of organism Compacted crystals

Environment of Formation Types of fossils (marine, freshwater) Size and shape of sediment Layers/Strata

Environment of Formation Types of fossils (marine, freshwater) Size and shape of sediment Layers/Strata of sediment, ripple marks

http: //www. classzone. com/books/earth_scien ce/terc/content/visualizations/es 0701 ce/terc/content/visualizations/es 2901 page 01. cfm? chapter_no=visualization (coal forming)

http: //www. classzone. com/books/earth_scien ce/terc/content/visualizations/es 0701 ce/terc/content/visualizations/es 2901 page 01. cfm? chapter_no=visualization (coal forming) Fossil forming http: //www. classzone. com/books/earth_science/terc/content/visualizations/es 0605/es 0 605 page 01. cfm? chapter_no=visualization cementation http: //www. coaleducation. org/miningtv/default. htm Coal mining videos http: //www. wwnorton. com/college/geo/egeo/animations/ch 12. htm Shale becomes oil http: //highered. mcgrawhill. com/sites/0072402466/student_view 0/chapter 10/animations_and_movies. html# Sediment transport http: //www. classzone. com/books/earth_scien ce/terc/content/visualizations/es 0604 page 01. cfm? chapter_no=visualization (sediments being deposited

http: //www. eram. k 12. ny. us/education/sctemp/0 c 525861 b 50 e 177 dace

http: //www. eram. k 12. ny. us/education/sctemp/0 c 525861 b 50 e 177 dace 8 b 634 d 0 e 0 d 5 f 7 /1203603040/sedimentary. swf

Relative Age Dating • Superposition – Oldest at bottom – Youngest at top

Relative Age Dating • Superposition – Oldest at bottom – Youngest at top

Relative Age Dating • Cross-cutting – Younger rocks (igneous intrustions/extrustions) or structures (folds, faults)

Relative Age Dating • Cross-cutting – Younger rocks (igneous intrustions/extrustions) or structures (folds, faults) cross-cut older rock

Complex Bedrock Structures Intrusions Folding (bending) Faulting (break) Tilting

Complex Bedrock Structures Intrusions Folding (bending) Faulting (break) Tilting

Faults, folding, tilting Folding (bending) Tilting

Faults, folding, tilting Folding (bending) Tilting

Relative Age Dating • Include Fragments – Sediment in the rock must be older

Relative Age Dating • Include Fragments – Sediment in the rock must be older than the rock itself – Ex: conglomerate

Relative Age Dating • Unconformity – A buried break or gap in rock sequence

Relative Age Dating • Unconformity – A buried break or gap in rock sequence – Missing rock record – Caused by: • erosion • Lack of deposition

http: //www 2. wwnorton. com/college/geo/egeo/flash/10_2. swf http: //www 2. wwnorton. com/college/geo/egeo/flash/10_1. swf

http: //www 2. wwnorton. com/college/geo/egeo/flash/10_2. swf http: //www 2. wwnorton. com/college/geo/egeo/flash/10_1. swf

 • • • http: //geography. cst. cmich. edu/Franc 1 M/Animations/animation_list_posted. htm alphabetical list

• • • http: //geography. cst. cmich. edu/Franc 1 M/Animations/animation_list_posted. htm alphabetical list of animations all different topics – animations http: //earthguide. ucsd. edu/earthguide/diagrams. html ! http: //emvc. geol. ucsb. edu/downloads. php 9 ice age, plate tectonics, etc differnt topics – found 4/24/08 Earth History http: //simile. mit. edu/timeline/examples/dinosaurs 2. html you can also make your own interactive timeline (tedious though) http: //simile. mit. edu/timeline/docs/create-timelines. html#getting-started Earth History http: //www. nmnh. si. edu/paleo/geotime/main/index. html geo time line http: //www. indiana. edu/~ensiweb/home. html http: //www. indiana. edu/~ensiweb/evol. fs. html evolution You can get glossaries at http: //www. litstudies. com/bilingual_esl/Bilingual. Glossaries/index. htm The main part of the screen will be white, but you can click on the languages on the left. It is actually from the remains of the http: //www. litstudies. com/bilingual_esl/index. htm and then http: //www. gly. uga. edu/railsback/Geological. Diagrams 1. html geology diagrams

Sedimentary Rocks Texture (3 types) • 1. Clastic – fragments of rocks cemented Land-derived

Sedimentary Rocks Texture (3 types) • 1. Clastic – fragments of rocks cemented Land-derived sediments eroded, and deposited(usually in water), buried, compacted and cemented. Ex: sandstone • 2. Crystalline (Chemical) – compacted minerals Dissolved minerals/salts precipitate out of water, settle, buried, compacted and cemented 3. Bioclastic (organic) – have fossils (shells, plant matter) Form from something once living ex: coal, coral http: //www. wiley. com/college/strahler/0471480533/animations/ch 12_animations/animation 2. html

CLASTIC CRYSTALLINE BIOCLASTIC

CLASTIC CRYSTALLINE BIOCLASTIC

http: //geography. cst. cmich. edu/Franc 1 M/Animations/animation_list_posted. htm - go to watersheds MISS

http: //geography. cst. cmich. edu/Franc 1 M/Animations/animation_list_posted. htm - go to watersheds MISS