Announcements
This presentation is the property of its rightful owner.
Sponsored Links
1 / 37

Announcements PowerPoint PPT Presentation


  • 57 Views
  • Uploaded on
  • Presentation posted in: General

Announcements. Reminder, this Saturday field trip . Meeting place/time: GS loading dock at 7:45 am. Bring hiking gear, lunches, water.

Download Presentation

Announcements

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Announcements

Announcements

Reminder, this Saturday field trip . Meeting place/time: GS loading dock at 7:45 am. Bring hiking gear, lunches, water.

Extra credit: get 1 point (test-equivalent; for each tectonics -related Geoscience colloquium attended between now and end of class). A list of colloquiums to attend will be posted on the web. Turn in a paragraph summarizing the main points of the talk.


Announcements

Normal faults

-rifted continental margins

-form in extension

-typical for continental and oceanic lithosphere

-jargon (horsts, grabens, listric, detachment)

-are they low-angle?

-core complexes

-Example: Basin and Range, -the way we think it works, mechanically

-

Normal fault systems(D&R: 340-357)


Announcements

Can you spot the fault?


Announcements

It’s low angle, but so are thrust faults:

KEY: puts young (hanging wall) on old

(footwall). The fault markers (slickenlines

Etc) are the same.


Announcements

Horsts and grabens

Iin agreement with Coulombian mechanics


Announcements

Some problems with the model-

Most faults look listric and low angle

Listric


Announcements

Pure shear or simple shear??


Announcements

Simple shear

A complication of simple shear


Announcements

How do extensional faults look like?


Announcements

Sedimentation takes place during faulting;

Also block rotation domino-style


Announcements

Cottonwood Canyon - this Saturday’s trip


Announcements

Figuring out timing of extension: 1. Magmatism

2. Sedimentation


Announcements

High angle faults are present too- East African rift large scale example

Moab fault


Announcements

Basin and Range- world’s

most studied extensional

province-low-angle normal

faulting prevails.


Announcements

How do continents break apart?


Announcements

A view of the Mountains north of us… the Catalinas


Announcements

Core complexes- metamorphic core


Announcements

Exhumation of metamorphic cores beneath detachment faults

Extension of the upper crust commonly requires flow in the mid- to low crust and/or magmatic additions


Announcements

Important things about normal faults.

1. Fundamental to structure of continents and oceans.


Announcements

Important things about normal faults.

2. Two different styles: the low-angle and high-angle.


Announcements

Important things about normal faults.

3. Can take up as much extension as compressional

orogens shorten.


Announcements

Important things about normal faults.

4. You live in the most famous (and perhaps

most important extensional region-the B&R).


Announcements

Important things about normal faults.

5. Extension is accompanied by big-time

sedimentation-important for oil formation.


Announcements

Important things about normal faults.

1. Fundamental to structure of continents and oceans.

2. Two different styles: the low-angle and high-angle.

3. Can take up as much extension as compressional

orogens shorten.

4. You live in the most famous (and perhaps

most important extensional region in the world-the B&R).

5. Extension is accompanied by big-time

sedimentation-important for oil formation.


  • Login