Exploring the Upper Cretaceous Hell Creek Formation, Montana: Through the Eyes of a Stratigrapher

This page was written by Jen Aschoff as part of the DLESE Community Services Project: Integrating Research in Education.

Terrestrial strata of the Hell Creek Formation, Eastern Montana.
Terrestrial strata of the Hell Creek Formation, Eastern Montana. Details
The goal of this section is to emulate the thought process of a field geologist using examples of places where you can see Cretaceous geology in the field. This section guides users through some common questions that geologists generate in an unfamiliar or unexplored area. Virtual field trips, photos, maps, short geologic discussions and in-depth technical papers are provided to help students understand the geology of some of these amazing "Cretaceous" places.
Read more about this pathway to discovery here...

The pathway begins with an interesting landscape primarily consisting of Cretaceous siliciclastic strata. Students are asked to make detailed observations of the outcrop at all scales beginning with the color, bedding style and architecture of beds. Hypotheses about depositional environments are formulated then tested with more detailed inspection of sedimentary structures, fossil types, grain size, composition and unconformities. Finally, students are given a suite of web resources such as additional outcrop photos at all scales, virtual field trips, technical reports and discussions to compare their observations and interpretations.

Read more about dynamic algorithms and why we use this pathway...

Such a pathway models the linear thought process of a professional stratigrapher as they view the landscape, make observations, formulate hypotheses, test hypotheses and make interpretations. By following dynamic algorithms that "real" geologists use to answer "real-life" problems students develop successful scientific thinking habits.

Preview part of this pathway...

  1. Describe the macroscale features of these rocks.
  2. What depositional environments may be recorded by these strata?
  3. How could you distinguish between possible depositional environments?
  4. Describe the sedimentary structures observed here.
  5. How does this information limit the range of possible depositional environments?
  6. List depositional environment interpretations for each of these beds. For units that require further inspection, generate some new hypotheses and methods for testing each hypothesis.
  7. Compare and contrast your interpretations with other geologists

Pathway to Discovery:

Part 1 Description

Detailed outcrop descriptions are a fundamental component of stratigraphy. Bedding character, architecture, color, sedimentary structures and grain size aid depositional environment interpretation. In this section students are given outcrop photos and web resources to aid description and generation of hypotheses.

Part 2 Generating and Testing Hypotheses

Generating and testing hypotheses form the foundation of the scientific method. Effective application of multiple working hypotheses and the scientific method is one of the most important skills students can learn because this allows them to answer a variety of "real-world" questions. This section explores the Hell Creek strata by generating and testing hypotheses that explain observations made in Part 1.

Part 3 The "Big Picture: Comparing Data, Methods and Interpretations

One of the most difficult tasks for students is "seeing the big" picture of the work they do and the literature they read. Making such connections is one of primary ways that truly unique, applicable ideas are formulated. In this section students are asked to summarize their interpretations and the evidence that supports their interpretations then compare and contrast their interpretations with previous work. They must then critique their own work, the work of others and suggest a future research project that addresses some unexplored or controversial aspect of the Hell Creek Formation.