Geology of Sonora Pass

Earth Science 35SP - Field Geology (1.5 units)

Instructor: Jeff Tolhurst, Ph.D.
Office: Sugar Pine 119
Office Hours:
By appointment during summer.
Phone: (209) 588-5235 office (+ msg)
Email: tolhurstj@yosemite.edu

http://directory.gocolumbia.edu/tolhurstj


Field Trip Forms


                                 

 


Geocaching and Earthcaching near Sonora Pass:

1. Sonora Pass
2. Columns of the Giants
3. Donnell Vista
4. Sword Lake
5. Trail of the Gargoyles


Facebook: Columbia College Geoscience Program Page


Powerpoint:

1. Field Geology of Sonora Pass

2. Geology of the Sierra Nevada


Online Resources:

1. Garry Hayes: You Just Can't Take Sonora Pass for Granite: (Geotripper Article)
2. Garry Hayes/Noah Hughes: Geological Excursions in the Sonora Pass Region: (Geotripper Article)
3. Dr. Cathy Busby
Professor of Tectonics, Sedimentology, and Volcanology: (Selected Publications)
4. Callan Bentley:
Mafic Volcanics atop felsic intrusives: Sonora Pass, California (AGU Blogosphere Article)

Suggested Reading:

1. Geologic Trips: Sierra Nevada by Ted Konigsmark, published by GeoPress, P.O. Box 964, Gualala, CA 95455.  This book is also available through Mountain Bookstore or from Bored Feet Press, P.O. Box 1832, Mendocino, CA 95460; (888) 336-6199, www.boredfeet.com.

2. Geology of the Sierra Nevada by Mary Hill, published by the University of California Press, Berkeley, CA, 94704, www.ucpress.edu.

3. Geology by Frank H. T. Rhodes, published by St. Martin's Press 175 Fifth Ave., New York, NY, 10010, www.stmartins.com.

4. "Rough-Hewn Land" by Keith Meldahl, published by University of California Press, 2013.


Objectives: Given information on the geological history and processes occurring near the Sonora Pass area, you will be able to explain/describe: 1) the main earth system processes that have formed and continue to shape the mountains; 2) describe the geologic history of the region; 3) explain the main geological processes observed in the area; and 4) relate the underlying geological controls to the ecology and biology of the area from biogeochemical cycling to tectonic and evolutionary processes.

Procedures:
The class will meet two times: 1) in class on campus (Monday, July 16th from 6-7:30 pm in Sugar Pine 115); for the trip (Friday-Sunday, July 20-22nd). The pre-trip meeting will cover information on what to bring, what to expect, and what to turn in for credit. We will also cover some information on the geological background of the Sonora Pass area to prepare us for the trip. A trip itinerary will be given.

Itinerary

Monday, July 16th: We will meet in Sugar Pine Room 115 for the pre-meeting for the class. Logistics and background information will be discussed to prepare us for the 3 days of field studies. We also need to complete all necessary field trip forms before we meet Friday.

Friday July 20th
:
8 am: Meet at Columbia College. Day will be spent examining geology of the Eureka Valley and Columns of the Giants area. We will see evidence of volcanic activity, glaciation and ice ages, geomorphology, and more. Moderate to strenuous hiking for parts of the day. Finish day at campus by 5:00 pm.

Saturday, July 21st: 8 am: Meet at Columbia College or Baker Station (TBD at the pre-meeting).  Day will be spent examining geology of Sonora Peak, Sonora Pass, and the Little Walker Volcanic Center.  Most of the day we will be driving to different locations and hiking to various geological features and outcrops. Moderate to strenuous hiking for parts of the day. Finish day at 5:00 pm.

Sunday, July 22nd
:
8 am: Meet at  Columbia College or Baker Station (TBD at the pre-meeting). Day will be spent at the Dardanelles and Eagle Meadows region. We will be examining granitic rocks, glacial valleys, glacial till and erratics, the Juniper Uranium Mine, and the Bennett Juniper tree (largest on Earth). Moderate to strenuous hiking for parts of the day. Finish the day by 5:00 pm.

What to Bring:

-- clothing for both warm and cold/wet weather
-- food lunch plus snacks for each day
-- sturdy hiking/walking shoes
-- sunscreen/chapstick
-- mosquito repellent
-- sunglasses
-- a hat
-- money in case of emergency needs
-- a learning log (to be turned in for credit)
-- a camera

-- other

What to Expect:

Expect warm as well as cold/possibly wet, rainy (afternoon thunderstorm) conditions along the river. Temperatures may range from about the mid to low 50's to the mid 90's during the day this time of year. Who knows what will happen - be prepared for changing conditions since it will be difficult to say what the weather will be like.

What to turn in for credit:

In order to assess your learning, I'll ask you to keep a field log for the trip. You will be expected to turn this in to me at the end of the class. This log should document the things you would like to learn before the trip as well as why you are taking the class (to be completed between the pre-meeting and the first day’s trip). You should also enter into your log the things you learned about: 1) the Sierra Nevada Mountains; 2) tectonics/faulting; 3) volcanism; 4) glaciers; and 5) geology/history of the region. You will be asked to make an entry at each stop on the trip as well as add an additional entry at the end of each day, reflecting on what happened during the day. There will be a final summary due at the end of the trip of your knowledge of concepts learned. Your final grade will be based on:

  1. A field log entry at each stop along the trip of observations and new material learned;
  2. An entry in your field log at the end of each day reflecting on what your overall impressions of the day were;
  3. Your final summary of what you learned at the end of the class.
  4. Quiz on geologic history and features observed in, and around, Sonora Pass. [Click here for the Quiz.]

Grading Scheme:

A = satisfactory completion of 1-3 above with strong demonstration of understanding of geological concepts encountered on the trip as evidenced by quiz score (90-100%). Also, appropriate conduct and behavior expected of a college-level geology student will be factored into your grade.  (Click here to read the Student Code of Conduct from the Columbia College Catalog)

B = some portions of field log incomplete; lack of comprehension of geological concepts observed as evidenced by quiz score (80-90%). Also, appropriate conduct and behavior expected of a college-level geology student will be factored into your grade.

C = incomplete field log; poor comprehension of concepts observed as evidenced by quiz score (70-80% correct). Also, appropriate conduct and behavior expected of a college-level geology student will be factored into your grade.

D = attendance on field trip only; no field log turned in; quiz score < 70%. Also, appropriate conduct and behavior expected of a college-level geology student will be factored into your grade.

F = no attendance or left trip early and did not turn any work in; no quiz taken. Also, appropriate conduct and behavior expected of a college-level geology student will be factored into your grade.

Note: I have had to add this statement based on past student behavior: 

No Smoking during field lectures and activities.  If you cannot adhere to this requirement you should not sign up for the course.  Due to past student health issues (asthma and other lung issues) smoking can be dangerous to others around you.

That having been said, I hope we all have a good trip! Feel free to contact me at the phone number, or email address, above if you have any questions before or after we leave.