1 / 46

Visualizing structures

Visualizing structures. An introduction to the geometry of geological structures in the field. Goals. To familiarize you with the 3-dimensionality of geological structures in the field Provide you with simple rules to use in geologic mapping of structures. 3D spaces to deal with.

magee
Download Presentation

Visualizing structures

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. Visualizing structures An introduction to the geometry of geological structures in the field

  2. Goals • To familiarize you with the 3-dimensionality of geological structures in the field • Provide you with simple rules to use in geologic mapping of structures

  3. 3D spaces to deal with • Topographic • Depositional/intrusive • Deformational They all intersect

  4. Non-shaded Shaded

  5. Any structures will intersect an irregular topography Try picturing how will a horizontal layer cut this relief

  6. Horizontal plane - follows topo contours

  7. Let us now put the real topography aside and step into the realm of “primary” geologic structures - layering of sedimentary units, intrusions, viewed in an idealized 3D framework

  8. Complicating the issue a little bit… Unconformity, what is it?

  9. Possible scenario: Deposition, erosion, deformation, new deposition

  10. The way this would look in a canyon near Page, AZ

  11. Igneous intrusions

  12. Structures on block diagrams

  13. Let us know try to drape structures onto topography and come up with some simple rules for the way they will plot on maps. To keep things simple for now, I will deal mainly with planes and not with lines. So what can a plane be? A bed, a fault, a dike, a sill an unconformity, anything that is planar.

  14. The simplest scenario: a horizontal bed

  15. Horizontal beds (a’la water line)

  16. Some shallow tilt of a plane

  17. Rule of v’s

  18. An example

  19. So then what is a geological map? An overlay of geologic structures (e.g. like the planes shown here on the 2D topographic map). Let’s take a look.

  20. Tucson Mts.

  21. Cross-sections

  22. Remember • The 3 spaces you deal with: topo, primary structures and deformational (secondary) structures); • Rule of v’s, overall topography/structure intersections of any planes • A structure looks very different depending from where you look at it!

  23. A preview of Cottonwood

  24. Be familiar with this lecture and this week’s lab - it will be important for Saturday’s exercise.

More Related