Painted Hills Painted Hills, Oregon

Geologic Field Methods

Prerequisites & Outcomes



Physical Geology or Geology of Washington and Physical Geology Lab (101 or 103, and 101Lab), Earth Evolution and Global Change (200), Introduction to Field Methods (210), Rocks and Minerals (320), Mineralogy (346), Structural Geology (360), and Stratigraphy (370) are required.

Physical Fitness

Field geology is a physically demanding course. It requires extensive hiking (up to 5-10 miles per day), often in hot or freezing weather (temperatures in the field can range from as high as 105°F to freezing hailstorms) and rugged, steep terrain. Thus, in addition to your academic preparation, good physical condition is an important prerequisite for a rewarding and enjoyable field camp. Field areas at the OSU field station, Oregon are at relatively low elevations, 1900' to 6600', and the terrain ranges from gentle slopes to steep canyons. These lower elevation map exercises will help you acclimatize for the higher elevations, from 6000' to as high at 10,000', and very steep terrain at the Lost River Field Station, Idaho. Field areas in both areas will entail scrambling over loose rock, crawling through bushes, and cross-country hiking. Starting the course in good physical condition will be in your best interest and will benefit your field partners.

Course Outcomes

  1. Develop the ability to locate oneself and geologic features on a map base such as topographic maps, aerial photographs, digital orthophotoquads, Google Earth Images, and/or LiDAR maps.
  2. Describe sedimentary, metamorphic, and igneous rocks from outcrop scale characteristics to hand lens scale, and combine similar rocks into mappable rock units.
  3. Describe and determine the nature of contacts—sedimentary, intrusive, or tectonic—and how well the contacts can be located on the map base using appropriate geologic symbols.
  4. Measure attitudes on sedimentary, intrusive, and tectonic structures (e.g. bedding, lineations, columnar joints, foliations, fault planes, etc.) and contacts, and interpret their geologic significance.
  5. Interpret the relative age relations among the different rock units using observations and data collected in #'s 2-4 above.
  6. Create a geologic map over a range of scales (e.g. 1:6,000 to 1:24,000 over areas ranging from 0.3 km2 to 4.3 km2) by plotting data collected in #'s 2-5 above on a base map, using appropriate geologic symbols at the appropriate location.
  7. Discover the limitations in quantity and quality of geologic field data.
  8. Visualize geology in 3D and construct accurate geologic cross-sections and interpretations based on field observations and data, and geologic maps.
  9. Develop sound interpretations based on uncertain, non-unique, and limited field data and observations, and with limited time for analysis.
  10. Apply knowledge from core geology disciplines to integrate and interpret diverse data sets into a coherent geologic history.
  11. Practice professional behavior in teamwork and collaboration in the field and in the camp, completing assignments on time, and participating in discussions.

Evaluation Criteria

Student Maps, Cross-sections, and Stratigraphic Columns

  1. General information—title, name, date, north arrow, scale, lithologic, and symbol keys.
  2. Presentation & legibility—product is inked & legible, includes appropriate color/shade, and map & key are in agreement.
  3. Geologic map information—contact locations (type, etc. on a map base) are accurate and indicated with appropriate solid, dashed, or dotted line.
  4. Identification of rock units.
  5. Identification of structures—attitudes measured in the field and plotted accurately (strike & dip, and trend & plunge of planar and liner features).
  6. Cross-sections—includes scale, accurate topographic profile, the cross-section geology is consistent with the geologic map.
  7. Stratigraphic columns—unit identification is accurate; rock/unit descriptions are detailed, complete, and well organized; unit thicknesses are accurate; a scale is included.

Student Notebook

  1. General information—date, map project, map base and scale, name, field partners.
  2. Use of station numbers, which are tied to rock descriptions, nature of contacts, contact relations, and other special features.
  3. Lithologic descriptions should include quantitative data such as grain size (metric), percentages, and mineralogy (e.g. quartz, orthoclase, biotite, etc.).
  4. Faults—strike & dip of plane; trend & plunge of striation; units juxtaposed across the fault; sense of offset; fault rock types exposed.
  5. Schematic diagrams (sketches of field relations, cross-sections, stratigraphic relations, etc.)—scale, orientation, labels, point of illustration.
  6. Interpretations—based on observations previously recorded in notebook.
  7. Contents should be neat and legible.

Student Field Work

  1. Preparedness—student has rock hammer, hand lens, notebook, maps, lunch, water, etc.
  2. Collection of data—student uses brunton compass, hand lens, and field observations to obtain structural, lithologic/mineralogic, and rock unit dimension information.
  3. Map reading—student can read topo map, orthophoto, &/or aerial photo and is able to accurately locate outcrops.
  4. Data recording—student records appropriate data in both the field notebook and on the map; uses clear and legible handwriting and symbols.
  5. 3D thinking—student is capable of mentally projecting surface outcrop relations into the subsurface dimension and understands the implications of doing so.
  6. Data integration—student is able to view his/her own data as well as data from other field parties as part of the bigger picture; student is able to see beyond the outcrop he/she is standing on.
  7. Attitude—student is willing to suffer a bit (cheerfully) for the sake of getting the job done; views this fieldwork as a learning experience.
  8. Flexibility—student is willing to consider and test new ideas and concepts.
  9. Teamwork—although individuality is encouraged, student is capable of effectively working as part of a team.
  10. Safety—student demonstrates safe field practices, including awareness of the location of other members of his party.
  11. Leadership—student demonstrates leadership abilities in planning and executing traverses, as well as other assigned work.

Student Camp Work

  1. Completing assigned duties (meal setup, dish cleanup, cleaning washrooms, and showers).
  2. Helps maintain clean field station grounds.
  3. Is courteous to others.
  4. Respects designated quiet time.

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