1 / 27

GEOL 3000 Geologic Maps

GEOL 3000 Geologic Maps. Determining the Relative and Absolute Age of Map Units. Relative Age Dating - Superposition. Up isn’t always Younging. Up Indicators. Graded Bedding. Pillowed Lavas. Amygdaloidal Zones in Lavas. Cross-bedding. Ripple Marks.

Download Presentation

GEOL 3000 Geologic Maps

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. GEOL 3000Geologic Maps Determining the Relative and Absolute Age of Map Units

  2. Relative Age Dating - Superposition

  3. Up isn’t always Younging

  4. Up Indicators Graded Bedding Pillowed Lavas Amygdaloidal Zones in Lavas Cross-bedding Ripple Marks

  5. Sedimentary Facies – Time Trangressive Units

  6. Paleogeography of Middle Laurentia in the Paleozoic

  7. Advanced Transgression Regression

  8. Paleozoic Formations of the Upper Midwest

  9. Principles of Faunal Successionand Faunal Assemblage Index Fossils - Widespread distribution - Restricted, known time of existence - Common to many environments

  10. The Jordan Sandstone Unconformity Missing Fossils

  11. Gaps in the Geological RecordUnconformities Siccar Point, Scotland “The mind seemed to grow giddy looking so far into the abyss of time” John Playfair – Illustrations of Huttonian Theory (1809)

  12. Creating Unconformities Nonconformity Grand Canyon Stratigraphy Angular Unconformity Disconformity

  13. Unconformities or Pinch-outs?

  14. Gaps in the Minnesota Timescale

  15. Regional Correlation of UnitsPiecing the Rock Record Together

  16. Relative Time for Intrusive Igneous RocksPrinciple of Cross-cutting Relationships

  17. Global Time MarkersVolcanic Ash Eruptions

  18. Global Time MarkersMeteor Impacts K-T Boundary mudstone-impact layer coal K-T impact site

  19. The 1.875 Ga Sudbury Impact The First Major Extinction Event ??

  20. Global Time MarkersMagnetic Reversals

  21. Global Time MarkersClimate Change

  22. Absolute Age DeterminationsRadiometric Dating

  23. Radioactive Isotopes

  24. Radioactive Decay

  25. Radioactive Decay Half-life Zircon ZrSiO4 U substitutes for Zr, but Pb does not.

  26. Rb-Sr Dating of a Granite 87Rb 87Sr; 86Sr is stable Rb – chemically substitutes for K Sr – chemically substitutes for Ca Isochron t=2 t=1 87Sr/86Sr Metamorphism at t=1 87Sr/86Sr°(m) t=0 87Sr/86Sr° 87Rb/86Sr Ca-plagioclase Granite whole rock K-feldspar Biotite (K-rich)

More Related