GEOL 415
X-RAY DIFFRACTION IN GEOLOGY

1. Catalog Entry

GEOL 415. X-ray Diffraction in Geology
Two hours lecture; four hours laboratory (4).

Prerequisite: GEOL 212

Includes a presentation of the basic theory of X-ray diffraction, the use of X-ray diffraction equipment to identify minerals, determine lattice types, parameters, and the indexing of diffraction lines. The application of the techniques and equipment to various geologic problems will be investigated. Laboratory hours will be scheduled on an individual basis with the instructor.

2. Detailed Description of Content of Course

Lecture Outline:

1. Introduction
2. Historical Aspects

a. Discovery of X-rays
b. Discovery of X-ray Diffraction
c. X-Ray Diffraction and Atomic Structure Determination
d. Overview

3. Production and Detection of X-rays

a. General
b. Continuous Spectrum
c. Characteristic Spectrum
d. Absorption and Monochronicity
e. Equipment Used

4. Basic Theory of X-Ray Diffraction

a. General
b. Generation of the Diffracted X-ray Beam
c. The Bragg Law
d. {HKL} Reflections
e. Intensities of Diffracted X-ray Beam
f. Lattice Reflections and Intensities
g. Indexing an Isometric Diffraction Pattern
h. Unit Cell Dimensions and Lattice Type
i. Number of Atoms in Unit Cell
j. Determination of Atom Positions (i.e., structure)

5. Application of X-ray Diffraction to Other Geologic Problems (the following are some examples of areas of coverage)

a. Mineral Identification
b. Percent Dolomitization
c. Determination of Amount of Ca replaced by Mg in Calcite
d. Weight % of Carbonates and Quartz in Rocks
e. Crystallite Size
f. Plagioclase Composition Determination
g. Clay Mineral Analysis

Laboratory Outline

1. Introduction to XDS 2000

a. Basic Operation
b. Safety
c. Sample Preparation

2. Basic Data Collection
3. Storage of Data
4. Data Display
5. Standards
6. Mineral Identification – 1
7. Mineral Identification – 2
8. Multi Phase Problems
9. Percent Dolomitization
10. Other projects that a student may work on depending on their specific interests.

3. Detailed Description of Conduct of Course

The course will be taught by lecture, lab, oral presentations, and discussion of projects between class members. The lab work will involve experiments designed to introduce the student to the general use of X-ray diffraction equipment and to specific applications in the geological sciences. Students will choose a specific laboratory investigation topic, do library research into background information on topic, and establish operational goals and methods of approach with the guidance of the instructor. The student will then obtain, prepare, and run samples on X-ray diffractometer. Analysis of data using computer assistance and graphical presentation of that data will be done by the student prior to writing a final paper on the project. The project will be presented to the entire class in oral form and a group discussion will then ensue.

4. Goals and Objectives of Course

Having successfully completed the course, the student will:

1. Have hands-on experience with laboratory methods and techniques used in investigation of many geological problems;
2. Have a basic understanding of the theory of X-ray diffraction; and
3. Have experienced using state-of-the-art X-ray diffraction equipment the same as, or similar to, that used in many consulting firms, businesses, and scientific institutions around the world.

5. Assessment Measures

1. Lecture written examinations
2. Graded laboratory exercises
3. Project results

a. Paper
b. Oral Presentation and Defense

6. Other Course Information
7. Approval and Subsequent Reviews

Date Action Reviewed By
August 2005 Reviewed and Approved Stephen W. Lenhart, Chair