Dexter Perkins

Peritectic Phase Diagram part of Petrology:Teaching Examples
An exercise to help students figure out what is going on with peritectic phase diagrams. It is NOT trivial.

Theriak-Domino Exercise part of Petrology:Teaching Examples
This multidimensional project involves using several different computer programs to calculate and interpret phase diagrams and pseudosections. So, students learn lots of skills at the same time. But, an overarching ...

Introduction to Gibbs Energy part of Petrology:Teaching Examples
This is a short project that can be used in-class or as homework. It involves just a few questions and it is intended to help students understand the idea of Gibbs free energy.

Simple Peritectic Exercise: Leucite-Quartz part of Petrology:Teaching Examples
This can be done as an in-class exercise (I use it as a group project) or as homework. It is intended to help students learn how to interpret and use peritectic diagrams.

Calculating a Simple Phase Diagram: Diamond=Graphite part of Petrology:Teaching Examples
This is a very short exercise designed to get students to understand how the Gibbs energy equation is used to calculate the location of a reaction in P-T space. I use it in-class and have students work on it in ...

A Fun and Effective Exercise for Understanding Lattices and Space Groups part of Mineralogy:Activities
This activity uses figures from Francois Brisse as Esher drawings to teach students about 2-dimensional symmetry, especially involving translation.

Mineral Synthesis and X-Ray Diffraction Experiments part of Mineralogy:Activities
This 6-week laboratory activity has students working in groups of two or more to synthesize a mineral and then analyze their mineral using XRD.

Schreinemakers Analysis - Problem #3: Analysis of an Invariant Point part of Petrology:Teaching Examples
This is a challenging Schreinemakers analysis problem.

T-X Phase Diagrams part of Petrology:Teaching Examples
This is a 15 page tutorial and problem set designed to get students familiar with T-X diagrams, their implications, and uses.

Schreinemakers Analysis - Problem #4 part of Petrology:Teaching Examples
This is a straightforward Schreinemakers analysis involving two invariant points.

Synthetic Alkali Halides part of Mineralogy:Activities
This is a complex experimental investigation of the melting of alkali halides. This project takes more than one class and involves using an X-ray diffractometer.

Crystallization and Melting of Diopside - Anorthite part of Mineralogy:Activities
This short exercise introduces students to the binary phase diagram in the diopside-anorthite system that contains a eutectic invariant point.

Examination of Igneous Silicates part of Mineralogy:Activities
Students study hand samples of light-colored igneous minerals and related mineral species. They look at some of the same minerals, and others, in thin section.

Reagents, Compositions, Weight Loss part of Mineralogy:Activities
This is a short experimental study of several different reagents and what happens to them when they are heated to 110° and 1200° C.

Mineral Classification - What's in a Name? part of Mineralogy:Activities
Students derive their own scheme for identifying and naming minerals. Examples include different minerals that have the same crystal forms, and mineral species that occur with numerous forms and varieties to ...

Mass Balance and Mineral Reactions part of Petrology:Teaching Examples
This is a short exercise to make sure that students understand mass balance and how the different starting assemblages may lead to different results after metamorphism. It is quick but not trivial.

Mineral Classification Exercise part of Mineralogy:Activities
This exercise gets students thinking about mineral classification and the properties that are most useful for classifying and identifying minerals.

The Nature of Science and Scientific Fraud part of GeoEthics:Activities
This is a peer-reviewed teaching activity page from the On the Cutting Edge collection that explores the nature of science and a case of scientific fraud in mineralogy, emphasizing critical thinking, ethics, and scientific integrity through investigative writing and discussion.

Collection of PT Phase diagram exercises part of Petrology:Teaching Examples
I am always needing more phase diagrams exercises so my students can practice problem solving. This collection includes 5 different exercises that can be used for homework, in-class, or for quizzes or exams.

Water Development: A Philosophical and Ethical Issue part of GeoEthics:Activities
This educational module page presents a peer-reviewed, multi-part teaching activity focused on the philosophical and ethical dimensions of water development, designed to cultivate critical thinking and ethical reasoning in students through case studies, readings from works like *Cadillac Desert* and *Encounters with the Archdruid*, and discussion-based learning across diverse educational levels.

Introduction to Ternary Phase Diagrams part of Petrology:Teaching Examples
Includes a number of hands-on exercises involving ternary phase diagrams. Some questions are quite easy, some are not.

Making Good Looking Diagrams from Theriak-Domino Output part of Petrology:Teaching Examples
This is a complementary exercise that follows "Using Theriak-Domino to Calculate Equilibrium Phase Diagrams." I have students do this because it brings closure to the other exercise and it teaches ...

TWQ Exercise part of Petrology:Teaching Examples
This is an exercise using TWQ to generate a phase diagram. It can be used as homework but is better done in a group.

Compatibility Diagram 2:Tc-En-Etc part of Petrology:Teaching Examples
One of three compatibility diagrams I use in class. This is a short activity that has students construct several compatibility diagrams in different fields on a phase diagram. This, in turn, can be followed by ...

Compatibility Diagram 1: Dsp-Py-Qz-Ka-H2O part of Petrology:Teaching Examples
One of three compatibility diagrams I use in class. This is a short activity to introduce students to compatibility diagrams (triangular diagrams showing stable assemblages) and how tie lines change when a reaction ...

Compatibility Diagram 3: Fo-Tc-Etc part of Petrology:Teaching Examples
One of three compatibility diagrams I use in class. This is a bit more complicated than #1 and #2. It involves a projection from H2O and non-standard corners on the composition triangle.

Plane Groups part of Mineralogy:Activities
Studying plane groups is a good way to introduce crystal systems, point groups, lattices, symmetry operators, etc. All is in 2-D, but it is easy to tell students that the principles are the same in 3-D. I provide, ...

Three Component Systems part of Petrology:Teaching Examples
This exercise involves plotting mineral compositions on triangular (3-component diagrams) and using those diagrams to determine possible mineral reactions.

Phase Diagrams and Chemographic Projections part of Petrology:Teaching Examples
This exercise is a good way to get students thinking about the phase rule, metastable and stable reactions and phase diagrams. It can be done in class or as homework.

Simple Eutectic Exercise: Diopside-Anorthite part of Petrology:Teaching Examples
This exercise can be done in-class (I use it as a group activity) or as homework. It is a quick way to get students to figure out how to use and interpret simple eutectic diagrams.

Three Component Systems and Their Reactions part of Petrology:Teaching Examples
This exercise involves plotting mineral compositions on triangular (3-component diagrams) and using those diagrams to determine possible mineral reactions.

Naming Igneous Rocks part of Petrology:Teaching Examples
This project is intended to introduce students to the IUGS rock classification scheme. Samples come from the Wards Collections (which many schools have). Students are provided with both hand specimens and thin ...

Plagioclase Phase Diagram part of Petrology:Teaching Examples
This is a short exercise aimed at evaluating whether students understand how to interpret the Ab-An phase diagram.

Plotting Compositions in 2-D and 3-D Space part of Petrology:Teaching Examples
This is a fairly short exercise that can be used for an in-class cooperative learning project or as homework. It includes LOTS of explanation and so is sort of a tutorial. I use it in my petrology class because it ...

Growing Crystals on a Microscope Stage part of Mineralogy:Activities
Many compounds crystallize rapidly from evaporating solutions, and many can be crystallized from melts. Because of this, it is possible to do simple crystallization experiments and to watch crystals grow over short ...

Schrinemaker Analysis - Problem #1: Analysis of an Invariant Point part of Petrology:Teaching Examples
This is a standard Schreinemakers problem: identifying the sequence of stable and metastable reactions around an invariant point.

Schreinemakers Analysis - Problem #2: Analysis of an Invariant Point with Application of the Clausius-Clapeyron Equation part of Petrology:Teaching Examples
This is a standard Schreinemakers problem: identifying the sequence of stable and metastable reactions around an invariant point. The added wrinkle is that they use the Clausius-Clapeyron Equation to calculate ...

Mole %, Weight %, Compositions and Projections part of Petrology:Teaching Examples
This is an introductory exercise intended to get students thinking about mole vs weight % and about the power and problems of projections.

Introduction to Crystal Structure: Bond Strength part of Mineralogy:Activities
This is an exercise to get students thinking about coordination number and bond strength It is really an application of Pauling's Rules, mostly rule #2

Properties of Minerals part of Mineralogy:Activities
Students examine a number of key mineral properties and how they are displayed by different minerals.

Metamorphic Rocks and Minerals part of Mineralogy:Activities
This exercise is an introduction to the most important metamorphic rocks and minerals.

Properties of Minerals and Intro to Polarizing Microscopes part of Mineralogy:Activities
This exercise continues the study of the physical properties of minerals and introduces petrographic microscopes.

Mineral Commodities part of Mineralogy:Activities
This exercise introduces students to mineral commodities.

Private Mineral Project - Part 1 part of Mineralogy:Activities
Students begin to work on semester-long private mineral projects.

Fun With Asbestos part of Mineralogy:Activities
This exercise is a practical application of optical mineralogy involving identification of some asbestiform minerals.

Using SHAPE to Make Crystal Drawings part of Mineralogy:Activities
In this exercise, students use SHAPE, a computer graphics program, to make crystal drawings.

Ore Minerals part of Mineralogy:Activities
Introduction to sulfides and other ore minerals.

First Look at Crystal Shapes part of Mineralogy:Activities
This is a short and simple exercise requiring students to examine and compare different crystal shapes.

Sedimentary and Related Minerals part of Mineralogy:Activities
This exercise is an introduction to sedimentary minerals and rocks.

Symmetry Summary part of Mineralogy:Activities
This summary exercise involves crystal system and point group identification and stereo diagram construction.

Point Groups part of Mineralogy:Activities
This exercise involves identifying symmetry in crystals and using that information to assign crystals to crystal systems and point groups.

Mafic Mineral Properties and Thin Sections part of Mineralogy:Activities
Students look at mafic igneous minerals, learning to distinguish and identify them in hand specimen. They also look at a few of the minerals in thin section.

Crystallizing Minerals from Aqueous Solutions part of Mineralogy:Activities
Students dissolve selected salts and other compounds in water, let the water evaporate, and examine the crystals that grow.

Plagioclase Phase Diagram part of Mineralogy:Activities
This short exercise involves the binary plagioclase "two-phase loop" phase diagram.

X-ray Analysis of Sand part of Mineralogy:Activities
This is an x-ray diffraction analysis of six sand samples and comparison with hand specimens.

Symmetry part of Mineralogy:Activities
This is an introduction to the basic symmetry elements.

A Last Look at Igneous Minerals in Thin Section part of Mineralogy:Activities
A final lab exercise that uses the optical mineralogy skills learned in the previous labs, and begins the transition to petrographic analysis of thin sections.

Introduction to Crystal Structures: Bond Strength (Pauling's Rule #2) part of Mineralogy:Activities
A look at Pauling's "electrostatic valency" principle.

Phase Equilibria part of Mineralogy:Activities
This is a short exercise that introduces basic thermodynamics.

Interpreting T-X Diagrams part of Petrology:Teaching Examples
This exercise is designed to help students learn how to interpret T-X phase diagrams. It also introduces them to the systematics of reactions involving a group of minerals.

Phase Diagrams part of Petrology:Teaching Examples
This is a somewhat lengthy homework assignment that introduces students to phase diagrams. It is a tutorial that stands alone and does not need much introduction.

AFM Diagram Quiz part of Petrology:Teaching Examples
This is a short problem set I use to determine if students know how to interpret AFM diagrams. I call it a quiz but it is really more of a learning experience. It works well as an in-class group exercise.

Introduction to Mineral Equilibria part of Petrology:Teaching Examples
This activity features a short problem set to be used in class. It helps focus the discussion, while providing a starting point for an introduction to mineral reactions and phase diagrams.

A Field Trip to See a Cross Section of the Crust and Samples of the Mantle part of NAGT:Our Work:Past Projects:Teaching in the Field:Field Trip Collection
A field trip guide for undergraduate geology students visiting diverse California sites to observe crustal cross sections and mantle xenoliths, emphasizing hands-on learning of ophiolites, blueschists, serpentinites, and San Andreas Fault geology within a two-week itinerary designed by the University of North Dakota Geology Club.

Private Mineral Gallery Walk part of Mineralogy:Activities
Public display of "private mineral" posters created by students and a group learning session based on the posters.

Mineral Structure 2 part of Mineralogy:Activities
Introduction to some basic crystal structures.

X-ray Analysis of Unknown Minerals part of Mineralogy:Activities
In this exercise, students use X-ray analysis to identify unknown minerals.

Stereo Diagrams part of Mineralogy:Activities
This exercise is an introduction to stereo diagrams.

Mineral Structure 3 part of Mineralogy:Activities
Introduction to silicate structures.

Photographing Minerals part of Mineralogy:Activities
Students take digital photographs of mineral specimens and learn how to manipulate them with Photoshop.

Knowledge Surveys part of Student Learning: Observing and Assessing:Activities
Knowledge Surveys consist of a series of questions that cover the full content of a course. The questions are designed to illustrate the different levels of understanding required for mastery of the content. Knowledge surveys can serve as both formative and summative assessment tools.

Advanced Modeling Programs: Theriak-Domino part of Integrating Research and Education:Teaching Phase Equilibria
Educational resource page detailing the Theriak-Domino software for calculating equilibrium phase diagrams and pseudosections in petrology, covering installation guidance, thermodynamic principles, applications with visual examples, strengths and limitations, problem sets, downloadable PowerPoint tutorials by de Capitani, and supporting references for teaching phase equilibria.

Activity Models part of Integrating Research and Education:Teaching Phase Equilibria
Educational page on thermodynamic activity models in mineralogy, covering ideal and non-ideal solution behavior, Margules parameters, activity-composition diagrams, and applications in geothermobarometry and phase equilibria calculations.

Fundamental Thermodynamic Calculations part of Integrating Research and Education:Teaching Phase Equilibria
Educational page on fundamental thermodynamic calculations in petrology, covering Gibbs free energy, reaction curves, activity models, Clausius-Clapeyron equation, and geobarometry, with examples like the GASP reaction for metamorphic pressure estimation.

Clapeyron Equation part of Integrating Research and Education:Teaching Phase Equilibria
Educational webpage detailing the Clapeyron equation in metamorphic petrology, covering its thermodynamic derivation, application in geothermobarometry, phase diagram analysis, and worked examples for calculating reaction slopes and P-T conditions, authored by Andrea Koziol and Dexter Perkins.

Pseudosections part of Integrating Research and Education:Teaching Phase Equilibria
Educational webpage explaining pseudosections—phase diagrams depicting stable mineral assemblages for a specific bulk composition—contrasting them with petrogenetic grids and illustrating their application in metamorphic petrology using THERMOCALC and Perplex modeling.

Gibbs Free Energy and Other Thermodynamic Functions part of Integrating Research and Education:Teaching Phase Equilibria
Educational webpage covering thermodynamic principles in geology, focusing on Gibbs free energy, phase stability, and metamorphic reactions, with detailed explanations of enthalpy, entropy, volume, and their role in determining reaction direction and equilibrium under varying pressure and temperature conditions.

Thermodynamics part of Integrating Research and Education:Teaching Phase Equilibria
Educational resource page on thermodynamics in geology, covering Gibbs Free Energy, phase diagrams, thermobarometry, and modeling programs like THERMOCALC and TWQ, with teaching exercises and data references.

Deriving and Balancing Metamorphic Reactions part of Integrating Research and Education:Teaching Phase Equilibria
Educational page detailing methods for deriving and balancing metamorphic reactions using phase equilibria, covering inspection, graphical analysis, and Gauss-Jordan reduction with mineralogical examples in a CaO-Al₂O₃-SiO₂ system.

Phase Diagrams (and Pseudosections) for Petrologists part of Integrating Research and Education:Teaching Phase Equilibria
This educational webpage, authored by Dexter Perkins and John Brady, serves as a comprehensive resource for petrologists, detailing standard phase diagrams and pseudosections—graphical representations of mineral equilibrium relationships governed by thermodynamics—while providing instructional content, downloadable diagrams (binary, ternary, metamorphic P-T and T-X), animations, problem sets, and external links for teaching phase equilibria in geoscience.

Method of Schreinemakers -- A Geometric Approach to Constructing Phase Diagrams part of Integrating Research and Education:Teaching Phase Equilibria
Educational resource page detailing the Schreinemakers Method—a geometric approach for constructing phase diagrams in multicomponent systems—covering invariant points, univariant reactions, compatibility diagrams, metastability, enantiomorphic projections, and practical steps for generating topologically correct reaction bundles, with applications in petrology and thermodynamics.

Mineral Formulae Recalculation part of Integrating Research and Education:Teaching Phase Equilibria
Educational webpage offering tools and methods for recalculating mineral chemical analyses into atomic proportion formulas, featuring spreadsheets for silicate minerals, teaching activities, and references on geochemical analysis techniques.

Advanced Modeling Programs: Introduction to the THERMOCALC Mineral Equilibria Modeling Software part of Integrating Research and Education:Teaching Phase Equilibria
THERMOCALC is a thermodynamic modeling software used in petrology and geochemistry for calculating mineral equilibria through inverse and forward modeling, including pseudosections, compatibility diagrams, and average PT thermobarometry, supported by an internally consistent dataset and specialized tools like drawpd.

Mineralogy: University of North Dakota part of Starting Point-Teaching Entry Level Geoscience:Studio Teaching in the Geosciences:Examples
This class is an introduction to fundamental mineralogy and mineralogical principles. The course is taught as a studio course, and significant emphasis is placed on helping students develop holistic learning ...

Introduction to X-ray diffraction part of Mineralogy:Activities
Students collect X-ray diffraction patterns for the experimental products obtained in a lab on Reagents, Compositions, Weight Loss.