Portable X-Ray Diffraction (XRD)
Exploration Technique: Portable X-Ray Diffraction (XRD)
|Exploration Technique Information|
|Exploration Group:||Field Techniques|
|Exploration Sub Group:||Data Collection and Mapping|
|Parent Exploration Technique:||Data Collection and Mapping|
|Information Provided by Technique|
|Lithology:||Rapid and unambiguous identification of unknown minerals.|
X-ray powder diffraction has been widely used in geology, environmental science, material science, and engineering for rapid identification of unknown crystalline substances since the 1940s, however these analyses were historically restricted to a laboratory setting. Additional uses include detailed characterization of crystalline samples, determination of unit cell dimensions, and quantitative determination of modal amounts of minerals in a sample. X-ray powder diffraction can also be applied to the identification of fine-grained minerals. More specifically, the technique can be used to distinguish between different clays and mixed layer clays that are optically similar, but form from distinctly different weathering and hydrothermal alteration processes.
Recent innovations have led to the development of a vibrating sample holder for use in XRD analysis. Such sample holders cause convection of a powdered sample during bombardment, allowing for analysis of samples with grain sizes between 5-150 microns. This capability drastically simplifies sample preparation and greatly reduces the number of moving parts required for the device to function, allowing for miniaturization and portability.
- Data Collection and Mapping
- Interpretation of the data requires access to the AMSCD mineral database (included in the XPowder software that ships with the Terra device) or to a standard reference file of inorganic compounds.
- Requires a relatively small amount of pure material that has been ground into a powder.
- Indexing of patterns for non-isometric crystal systems can be complex for unit cell determinations.
- Peak overlay may occur for some samples and becomes worse for high angle “reflections.”
Cullity, B. D. 1978. Elements of X-ray diffraction. 2nd ed. Addison-Wesley, Reading, Mass.
Eby, G.N., 2004, Principles of Environmental Geochemistry. Brooks/Cole-Thomson Learning, p. 212-214.
Klug, H. P., and L. E. Alexander. 1974. X-ray diffraction procedures for polycrystalline and amorphous materials. 2nd ed. Wiley, New York.
Moore, D. M. and R. C. Reynolds, Jr. 1997. X-Ray diffraction and the identification and analysis of clay minerals. 2nd Ed. Oxford University Press, New York.
- X-ray Powder Diffraction (XRD)
- Technology Overview of InXitu XRD/XRF Products
- Vibrating Sample Holder for XRD Analysis with Minimal Sample Preparation
<ref>tag; no text was provided for refs named
Cite error: Invalid
- X-Ray Reflection in Accordance with Bragg’s Law
No exploration activities found.