NEWS & EVENTS
Geology Modules
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    Geology Modules

     

    Exploring the Formation of Geologic Structures, Module 1: Elasticity and the Mechanisms of Dike Emplacement
    Exploring the Formation of Geologic Structures, Module 1: Elasticity and the Mechanisms of Dike Emplacement -- For Instructors
    Exploring the Formation of Geologic Structures, Module 1: Elasticity and the Mechanisms of Dike Emplacement -- Assignments
    Exploring the Formation of Geologic Structures, Module 1: Elasticity and the Mechanisms of Dike Emplacement -- Data 


    Module Author: Linda Reinen
    Author Contact: lreinen@pomona.edu
    Funded By: National Science Foundation

     

    This module is designed for students in an undergraduate course in Structural Geology. While the key concepts are described in this module, it is assumed that students will have access to a good structural geology textbook to augment the information presented here. This pair of modules investigates the effects of three-dimensional discontinuities on the stresses and displacements resulting from elastic deformation in the surrounding host rock. The first module looks at dike emplacement, and what can be learned about magmatic systems (e.g., the magmatic driving pressure, the relationship between magma pressure and regional stresses). The second addresses stresses associated with faulting and how they may lead to the formation of additional faults and/or earthquakes.

    Learning goals for the first module:

    • Learn how to use numerical methods to investigate the elastic response in physically complex systems.
    • Determine the stresses created by an opening crack and the implications for further crack growth.
    • Compare the solutions determined from the numerical and analytical solutions to assess the viability of the numerical solution.
    • Use the skills developed in solving the previous problems to investigate the conditions of formation of a dike near Ship Rock, New Mexico.

    This module is implemented using Poly3D, a three-dimensional boundary-element numerical code which calculates the displacement, strain, and stress fields in a linear elastic whole or half-space. Poly3D was selected due to its relative ease-of-use and availability (annual licenses can be acquired for a nominal fee from IGEOSS). This module was written using Poly3D version 2.1.8.

    Exploring the Formation of Geologic Structures, Module 2: Elastic Deformation in Response to Slip on Transform Faults
    Exploring the Formation of Geologic Structures, Module 2: Elastic Deformation in Response to Slip on Transform Faults -- For Instructors
    Exploring the Formation of Geologic Structures, Module 2: Elastic Deformation in Response to Slip on Transform Faults -- Assignments 


    Module Author: Linda Reinen
    Author Contact: lreinen@pomona.edu
    Funded By: National Science Foundation

     

    This module is designed for students in an undergraduate course in Structural Geology. While the key concepts are described in this module, it is assumed that students will have access to a good structural geology textbook to augment the information presented here. This pair of modules investigates the effects of three-dimensional discontinuities on the stresses and displacements resulting from elastic deformation in the surrounding host rock. The second addresses stresses associated with faulting and how they may lead to the formation of additional faults and/or earthquakes.

    Learning goals for this module:

    • Learn how to use numerical methods to investigate the elastic response in physically complex systems.
    • Determine the stresses created by movement on a transform fault and the implications for further faulting.
    • Compare the solutions determined from the numerical and analytical solutions to assess the viability of the numerical solution.
    • Use the skills developed in solving the previous problems to investigate the faulting in the Cerro Prieto geothermal field in southern California.

    This module is implemented using Poly3D, a three-dimensional boundary-element numerical code which calculates the displacement, strain, and stress fields in a linear elastic whole or half-space. Poly3D was selected due to its relative ease-of-use and availability (annual licenses can be acquired for a nominal fee from IGEOSS). This module was written using Poly3D version 2.1.8.

    Drainage Patterns Module
    Drainage Patterns Presentation
    Drainage Patterns Accessories 


    Module Author: John B. Ritter
    Author Contact: jritter@wittenberg.edu
    Funded By: National Science Foundation


     

    Digital elevation models (DEMs) have transformed the way we analyze landscapes, from mapping and classifying landforms to modeling watershed hydrology or landscape development. In this module, students use DEMs to delineate drainage networks, distinguish between different drainage patterns, and model random drainage patterns. Students also compare your extracted drainage pattern with that depicted on standard topographic maps in order to investigate problems associated with defining stream origins and the network extent.

    Exploring and Visualizing Strain 


    Module Author: Linda Reinen
    Author Contact: lreinen@pomona.edu
    Funded By: W. M. Keck Foundation

     

    This module is designed for students in an undergraduate course in Structural Geology. While key concepts are described here, it is assumed that students will have access to a good structural geology textbook to augment the information presented here. Learning goals: (1) Understand how to quantify strain and apply that knowledge to real geologic situations. (2) Understand the rates at which rocks strain. (3) Understand the difference between pure shear, simple shear, and general shear. (4) Explore the differences between incremental and finite strain, and the clues that rocks can provide to decipher whether the strain recorded is pure or simple shear, or a combination of both. (5) Apply strain path models to decipher the strain history of natural rocks from different locations, including Norway, Joshua Tree National Park, California and Ganymede. This module is implemented using Microsoft Excel and a standard drawing program, such as Canvas or Adobe Illustrator. These programs were selected due to their widespread availability and relative east-of-use.

    Stresses and Faulting 


    Module Author: Linda Reinen
    Author Contact: lreinen@pomona.edu
    Funded By: W. M. Keck Foundation


     

    This module is designed for students in an introductory structural geology course. While key concepts are described here, it is assumed that the students will have access to a good textbook to augment the information presented here. Learning goals: (1) Understand the role of gravity and rock properties in producing stresses in the shallow Earth. (2) Graphically represent stress states using Mohr diagrams. (3) Determine failure criteria from the results of laboratory experiments. (4) Explore the interaction of gravity-induced and tectonic stresses on fault formation. (5) Apply models of fault formation to predict fault behavior in two natural settings: San Onofre Beach in southern California and Canyonland National Park in Utah. The module is implemented entirely using Microsoft Excel. This program was selected due to its widespread availability and relative ease-of-use. It is assumed that students are familiar with using equations and graphing tools in Excel.

    Spherical Magma Reservoir Failure: Exploring Some Geological Implications of Stress Concentration Around a Pressurized Cavity 


    Module Author: Eric Grosfils
    Author Contact: egrosfils@pomona.edu
    Funded By: W. M. Keck Foundation


     

    This module, which requires only a basic understanding of geology and calculus, explores a key process in shallow volcanic systems: shallow magma reservoir failure. The learning goals are as follows: (1) To introduce you to an important volcanological problem into which insight can be gained using both analytical and numerical modeling approaches; (2) To provide you with experience assessing the strengths and limitations involved when using boundary condition approximations in an analytical model—real insight can be gained but real caution must be exercised; and (3) To introduce you to the process of solving a structural failure problem under a wide variety of different conditions using a numerical technique, the finite element method, and promote comparing the results from this approach to the analytical results obtained previously. The analytical component of the module is implemented in its entirety using Microsoft Excel. This component can be used in “stand alone” mode, but it derives additional value via an extra numerical modeling section which introduces you to the process of finite element modeling (employing the commonly used and inexpensive program FEMLAB, which complements MATLAB) as a tool for continuing to explore the process of magma reservoir evolution. Note that having access to at least one copy of FEMLAB is handy but FEMLAB need not be available to use the numerical modeling portion of the module. If FEMLAB is not available a free viewer will need to be obtained to allow you to view and explore—fortunately in considerable depth—the results from pre-run model simulations.

    Thermal Conduction: A Tool for Exploring Geological Processes 


    Module Author: Eric Grosfils
    Author Contact: egrosfils@pomona.edu
    Funded By: W. M. Keck Foundation


     

    This module, designed for use by students with a rudimentary understanding of geology and calculus, introduces students to the derivation of basic thermal conduction and diffusion equations. The learning goals are as follows: (1) To introduce students to a number of important geoscience problems into which insight can be gained using thermal conduction and diffusion equations; (2) To provide students with experience solving simple boundary condition problems and more complicated infinite half-space problems using standard analytical methods as well as semianalytical methods which benefit from but do not explicitly require the use of computational tools; (3) To introduce students to the process of solving thermal problems using a numerical technique, the Fast Fourier Transform, and promote comparing the results from this approach to the analytical results obtained previously. The module is implemented in its entirety using Microsoft Excel. While some components of the module such as the Fast Fourier Transform could be implemented readily using more powerful software (Matlab, etc.), Excel is employed here because of its low cost and widespread availability to students in almost any field of study.

    Landslides and Slope Stability Analysis Module 


    Module Author: John B. Ritter
    Author Contact: jritter@wittenberg.edu
    Funded By: Battelle


     

    Landslides are a persistent cause of economic loss in every region of the United States, amounting to billions of dollars in property losses annually according to the U.S. Geological Survey (e.g., U.S. Geological Survey, 1982; Spiker, E.C. and Gori, P.L., 2000; Spiker, E.C. and Gori, P.L., 2003). One strategy for reducing losses from landslide hazards is to delineate susceptible areas for planning and decision-making purposes, the ultimate goal of this module. The objectives of this module will build toward that goal; they are to (1) explore different types of mass wasting processes using on-line resources and recent mass wasting events; (2) evaluate the sensitivity of slope stability to topographic and earth material variables according to the infinite slope method; and (3) assess the spatial variation in slope stability using a Geographic Information System (GIS). The final objective will focus on the urbanized area of Cincinnati and Hamilton County in southwestern Ohio. The highest documented per capita losses due to landslides, amounting to $5.80 per person per year, occur in Hamilton County, in the metropolitan area of Cincinnati (Fleming and Taylor, 1980). The module uses an infinite slope stability model to calculate a factor of safety. The infinite slope model is based on algebraic manipulation of various raster data layers to produce a map of factor of safety values and as such is a deterministic analysis of slope stability. It is particularly appropriate for slope failures with planar slip surfaces, such as translational slides, which are common in this area (Baum and Johnson, 1996).

    Numerical Analysis for Heat Transfer-Another Tool for Exploring Geological Processes
    Key Figures
    Supporting Documents: 1
    Supporting Documents: 2 


    Module Author: Sylvan Long and Eric Grosfils
    Author Contact: egrosfils@pomona.edu
    Funded By: National Science Foundation (0618252)

     

    This module, designed for use by students with a rudimentary understanding of geology and basic calculus (comfortable with derivatives and integrals), introduces students to finite element modeling and data analysis techniques. While designed as a stand-alone product, the intent is ideally to build upon the framework established in the module "Thermal Conduction-A Tool for Exploring Geological Processes," which introduces students to the derivation of analytical thermal conduction and diffusion equations and their application to basic heat transfer problems in geology.