Geology of the Sierra Nevada
Summer 2020

Instructor: Jeff Tolhurst, Ph.D.
Office Hours:
By appointment
(209) 588-5235 office (+ msg)
Course Credit:
1.5 semester hours
Day and Time:
Premeeting on Tue, June 23, from 6:00-7:30 pm (online, log onto Canvas)
Online and in the Field
Geology by Frank H. T. Rhodes (optional), published by St. Martin's Press, 175 Fifth Ave., New York, NY, 10010,

Field Trip Forms

Objectives: Given information on the geological history as well as the main geologic processes that have occurred, and continue to occur, in the Sierra Nevada mountains. You will be able to describe how these mountains have been shaped it into what they are today.

Procedures: We will meet once online via Canvas (on Tuesday, June 23rd, from 6-7:30 pm), then you will do a self-guided tour of parts of the Sierra Nevada mountains in Calaveras and Tuolumne Counties. The pre-trip meeting will cover information on what to bring, what to expect, and what to turn in for credit. You will also create a geocaching account for the trip. We will also cover some information on the geological background of the Sierra Nevada to prepare you for the trip. A trip itinerary will be given.


Note: With the current COVID-19 shelter-in-place requirements, there will be some uncertainties and ambiguities along the way. Please abide by all safety and health recommendations to be as safe and as comfortable as possible. Please be willing to adapt to changes...


  1. Tuesday, June 23rd: Pre-meeting: Log onto and sign into Canvas. You will also log onto and create an account. You will be shown a list of EarthCaches in Calaveras and Tuolumne Counties. Read each Earthcache and be prepared to answer the questions posed for each before you leave for the field each day.
  2. Friday, June 26th: You will navigate to, and accurately log, a minimum of 5 Earthcaches.
  3. Saturday, June 27th: You will navigate to, and accurately log, a minimum of 5 Earthcaches.
  4. Sunday, June 28th: You will navigate to, and accurately log, a minimum of 5 Earthcaches.

What To Bring:

  • clothing for potentially very hot and cool weather
  • food - pack a lunch for the day
  • sturdy hiking/walking shoes
  • sunscreen/chapstick
  • sunglasses
  • a hat
  • money in case you need to stop at at store
  • a field journal
  • a smartphone, or tablet, or laptop with internet connectivity to log Earthcaches
  • other

What to Expect:

Expect it to be hottest at lower elevations and cooler at higher elevations. The weather is usually nice there this time of year, but it can range from very hot to very windy at times, to cool at night. Expect a healthy chunk of time to be spent driving to Earthcaches. Most of them will be easily accessible by vehicle. There are a few, however, that you will have to hike to find and log.

What to Turn in for Credit:

In order to assess your learning, I'll ask you to log each Earthcache you find on the trip. A final summary of what you learned on the trip about the Geology of the Sierra Nevada will be required for full credit. All work will be turned in online. To summarize, turn in the following:

  1. A description of your Background with a photograph of yourself, entered on Canvas.

  2. An accurate log for 15 (or more) Earthcaches found in Calaveras and Tuolumne Counties and a photo of yourself at each Earthcache site, documenting your find.

  3. A 3-4 page summary of what you learned including: 1) the geologic history of the Sierra Nevada; 2) igneous processes; 3) metamorphic processes; 4) sedimentary processes; and 5) tectonic processes (subduction/compression, rifting/extension, faulting, and folding). Basically explain how the Sierra Nevada mountains formed. (Note: Use 1" margins, Arial or Time New Roman 12 point font, and double spaced text and submit online through Canvas in one of the following formats (MS Word; Google Docs; Adobe PDF).

Grading Scheme:

A = Satisfactory completion of 1-3 above; 15 or more Earthcaches logged accurately; strong demonstration of understanding of geological concepts demonstrated in the summary paper. 

B = Satisfactory completion of 1-3 above; 10-14 Earthcaches logged, some inaccuracies; moderate comprehension of geological concepts observed in the summary paper.

C = Satisfactory completion of 1-3 above; 5-9 Earthcaches logged, some inaccuracies; poor comprehension of geological concepts observed in summary paper.

D = Unsatisfactory completion of 1-3 above; <5 Earthcaches logged; no summary paper turned in.

F = No attendance or left trip early and did not turn any work in.

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)


I hope we have a good field experience! Feel free to contact me at the number or email address above if you have any questions.

Additional Resources:

  1. Geocaching Help Center
  2. List of Earthcaches
  3. Geology of the Sierra Nevada Powerpoint (from class)
  4. Geologic History of the Sierra Nevada
  5. Geology of the Sierra Nevada by Mary Hill