Initial Publication Date: October 11, 2013

Evolution of the Precambrian Rocks of Yellowstone National Park and Surrounding Areas--an NSF/REU Project

David Mogk, Montana State University and Darrell Henry, Louisiana State University

The Yellowstone REU Project explored the Precambrian basement exposed in the northern part of Yellowstone Park. Field studies were conducted with two cohorts of students during the summers of 2010 and 2011. The project goals were to: 1) characterize the igneous and metamorphic petrology, geochemistry, geochronology, sedimentology and structural geology of this unique sequence of Precambrian rocks, 2) integrate these findings with a larger ongoing research effort on the petrogenesis and evolution of Archean continental crust in the Wyoming Province, and for the students, 3) contribute to the professional development of cohorts of students who are ready to pursue the next steps of their careers in graduate school or in the workforce. The following is a summary of the development and implementation of this field program.

Project Goals

The project goals were to produce great Science and great Scientists.

  • The Science goals were to describe and interpret a suite of Precambrian rocks in an area that had very little scholarly work completed. This area filled a major gap in our knowledge about this area to contribute to regional tectonic interpretations.
  • For the students, our goal was to provide a complete research experience to help them develop geological skills, gain self-confidence in their ability to work in a field research setting, to build competence and capacity for the workforce for the 21st century, and to initiate these studnets into the "community of geological practice".

Project Vision

The project was envisioned as a true research experience that would

  • Be meaningful and relelvant to students' professional development
  • Apply "core" concepts and content from the geoscience curriculum
  • Utilize the strong affective component of working in the field
    • Curiosity, awe and wonder as motivators to learn
    • Engage collaborative and cooperative work
    • Impart a sense of "ownership" to the students for the success of the larger project
    • Make students responsible for personal contributions
    • Develop a trusting work environment
  • Provide students the opportunity to experience the excitement ofmaking truly new scientific discoveries.

Selecting the Right Team

Student in the field

A large part of the success of the program involved selection of students who had a keen interest in participating in the program, and who had the academic and personal attributes that would lead to their success. Field work in a remote setting can be physically, intellectually, and emotionally challenging. We had over 100 applicants to this project in each year, and we selected our participants according to these criteria:

  • Diversity;we sought gender balance, participation among underrepresented groups, type of home institution (we had roughly equal numbers from Research I, comprehensive, and liberal arts schools), geographic distribution, and declared geologic interests. We needed a team with diverse geologic interests to contribute to an integrated geologic history of the study area.
  • Academic preparation; we were looking for geology majors who had completed most of their geology core courses (e.g petrology and structural geology were emphasized), and who had some type of prior field instruction (field camp or field methods course). Our intent was to further refine knowledge and skills learned in the class setting, but the nature of our project did not permit time to do initial instruction in topics like rock and mineral identification or measurement of strikes and dips.
  • Letters of Recommendation;we were looking for evidence that students were active and engaged learners, who were self-motivated and capable of independent work, and at the same time worked well in groups with faculty and peers.
  • Personal Letters; Beyond basic academic preparation, we were looking for students who were excited about he prospect of joining the prject and who displayed a sense of curiosity about the world around them. Examples of independent work (of any kind) at their home institution was a premium, as was a keen interest to work in a natural setting.
  • Other: Other life experiences such as travel, service activities, etc. made the students more attractive in our review process. Because of the physical demands of our project, we also looked favorably upon athletes (not just varsity athletes, but also mountain bikers, climbers), and training as an EMT or Wilderness First Responder was also an added asset (skills that we had to use!).


Expectation management was a key to the success of this program. It was very important that we clearly identified the nature of the project, the challenges, and opportunities. We did this throughout the project via:

  • Initial advertising using the Yellowstone REU Project website, announcements distributed on listservs and in printed materials.
  • Closed Project Website;prior to the summer field experience we posted essential information for the participants:
    • Tentative schedule and itinerary, with contact information
    • A "wiki" posting board where students posted introductions to themselves, personal interests, and pictures (similar to Facebook).
    • Relevant literature to introduce students to the regional geology, prior work, methods, and to put the project in the context of the larger understanding of our long-term research interests.
    • Research goals, with suggestions about how the students could contribute
    • Equipment check lists
    • Disclaimers: about physical demands (long days in the field, hikes of 15+ miles/day; weather, bears).

Project Design

The overall project was designed as a "cradle to grave" research experience that included:

Field work; with an emphasis on sampling and mapping

  • Within the context of the larger project, students formulated their own research questions.
  • Students planned and executed their own reserch plans
  • Conducted mapping and sampling as required to address their research question;
  • Were responsible for daily compilations of data, archiving samples to be sure that all research objectives were achieved before we left the field.

Analytical Studies; during the following school year students continued their work through petrographic analysis of thin sections, and then through subsequent visits to major analytical facilities to collect data required to address their research questions. Depending on the nature of the problem, various students used an electron microprobe to obtain mineral compositional data, XRF for whole rock major and trace element data, or LA-ICPMS to obtain zircon U-Pb age dates.

  • Students were responsible for sample preparation (cutting thin section billets, crushing rocks)
  • Analytical data collection: standardization, data collection, data reduction, data representations...

Communicating Results;all students contributed to

  • Students also used project resources for a senior thesis or independent study project at their home institutions.
  • Students wrote abstracts and presented posters at the 2010 GSA Rocky Mountain Section Meeting

Developing Professional Expertise

Our research project was designed to systematically develop professional expertise. We very deliberately introduced students to a series of scaffolded and integrated experiences to build the totality of their research experience. Students were engaged in:

Field Work: Learning by Design

The summer itinerary was planned to systematically develop knowledge and skills in the students so that they could work in small groups to achieve meaningful results. This work plan included:

  • an introduction to all major rock units
  • daily field activities were purposefully designed to sequentially expose students to new rock types, structures or field relations; expertise was built in a deliberate way as students discovered key features, learned to describe and interpret them, such that after ~ 2 weeks they could work independently in the field and collect meaningful and relevant data in appropriate contexts.
  • Real-time tutorials and demonstrations--Field notes, measurements, sampling methods
  • Calibration of student observations to make sure all students could identify rocks and measure structures accurately
  • Logistics--
    • Students dentified daily objectives, where to go, what to do
    • Planned daily traverses, pick up points
    • All were involved with safety checks, equipment (radios, first aid, water filters...)
  • Instructors did regular "talk-throughs" to articulate what ami I doing and why? This helped to develop metacognitive aspects of the students' field work

Research Design and implementation

  • Semi-autonomous work by small groups to identify key targets, attain sampling or mapping goals, identify daily objectives and determine the logistics needed to accomplish the daily tasks.
  • Each student assumed leadership to pursue research gaols; all served in this capacity to direct the field group to accomplish the daily goals
  • Each student contributed to the overall research effort; a) assuming responsibility for their personal research project and b) contributing to the whole (e.g. collecting samples in areas where other groups would not otherwise go).
  • Emphasize that real contributions will be made; this is the real thing!
  • We worked very hard to develop TRUST and RESPECT among the students.

Sample Preparation

  • Students worked collectively to prepare all samples collected in the summer for future analysis. This included cutting billets for thin sections, coarse crushing and using a disk mill for mineral separates, and using a shatterbox to prepare powders for XRF analysis.
  • Professional standards were adhered to at all times: Concern for safety using heavy equipment (ear and eye protection)
  • Cleanliness (concern about cross-contamination between preparationof sample
  • Archiving samples and keeping accurate records of stages of sample processing

Analysis--all students visited one of our analytical labs during the academic year. They experienced the full range of procedures required to obtain publishable data:

  • Sample preparation (mapping of thin sections for EMPA work; pressing XRF pellets; separating zircons for geochronology...)
  • Experimental design--determining what to analyze and why?
  • Standardization
  • Replication of data
  • Data acquisition, reduction and representation.

Communicating Results

  • Eight integrated posters were presented at the Rocky Mountain GSA meeting
  • Abstracts were authored by students individually or in groups (heavilly edited by the instructors)
  • Students designed their posters and decided essential information to report (using a template provided by the instructors to make sure that all posters had the same look and feel)
  • Students attended a pre-meeting writing workshop to review the data and to prepare students for their presentations.
  • Students actively engaged professional discourse at the meeting.
  • Each poster will eventually be a section in a GSA Bulletin-style article.

Progress Measured:

A variety of assessment instruments were used to determine the extent to which project goals were achieved.

Science Goals

Were measured be the research outcomes which answered our specific research questions. The 2010 cohort: a) interpreted the environment of deposition of the turbidite sequence, and U-Pb detrital zircon data demonstrated that the provenance of these rocks was not the adjacent Beartooth massif; b) two epizonal, peraluminous plutons have an age of 2810 Ma; c) metamorphic grade increases from chlorite-garnet zone in the west to sillimanite zone in the east, with peak metamorphism at ~620oC and ~4 Kb; d) the Garnet Hill area is an injection migmatite area; e) three stages of folding pre-date the intrusion of the plutons (i.e. are Archean in age), and mylonite zones cut both the metasedimentary rocks and the plutons; f) the Junction Butte area is underlain by a 3.2 Ga gray gneiss unit. Results of the 2011 cohort are in progress, but initial results show that the magmatic complex near Slough Creek area show that these rocks are dominantly metaluminous and are distinct from both the western epizonal plutons and magmatic rocks in the Beartooth massif.

  • One measure of success was the presentation of 8 student-authored posters at the 2011 GSA Rocky Mountain Section meeting of GSA; one student was awarded best poster award.

Student Goals:

We were interested in documenting the growth of students as they progressed through the project. We used these instruments to document these changes:

  • Daily reflective journals to document their most important obsrvations of the day, to identify questions and issues they encountered, pose new questions, and make plans for future work.
  • De-briefs after dinner: Group dinners were always followed by a round table discussion of what each student or small group found that day; this was important to keep everyone abreast of new discoveries made, key relations, areas that merited further work; it served to inform focused research groups on new areas to visit to further achieve their research goals. Basically it kept everyone connected to all parts of the project.
  • Compilations: students were required to log in all samples for the day, including GPS coordinates, rock description, and reason why a sample was collected (e.g. petrography to identify minerals; zircon sample, whole rock geochemistry sample). Sample inventories were essential to a) make sure we were on task to have all required samples collected by the end of the field season as required to address our scientific objectives, and b) to make sure that we were working within the guidelines of our collecting permit from the National Park Service. Similarly, structural data (foliations, lineations) were collected in a spread sheet by structural domain for future plotting on stereonets. All data in this project was shared via our closed listserv so that all students would have access to maps, field photos, structural data, and eventually geochemical data for use in their own research projects at their home institutions.
  • Observations: the instructors continuously monitored the progress of students in the field, sometimes letting the students learn through their own experience, at other times intervening to make corrections as needed in real-time.
  • Surveys: we did pre- and post-activity surveys to measure student growth. Self-confidence logs were used to determine the extent to which students gained confidence in their ability to identify rocks, measure structures, conduct research. Open narrative responses were also solicited.
  • Videotaping: we worked collaboratively with a linguistic anthropologist who specializes in master-novice relations to document our interactions with students in the field. The analysis of these videotapes will be the basis for our future scholarship on how students learn in the field. (Be sure to get IRB approval before using student subjects in this type of research!).
  • Senior Thesis/Independent Study projects; almost all of the students used the summer field experience as the basis for their independent study or thesis projects at their home institution.