Institute of Geology and Dynamics of the Lithosphere at the University of Göttingen



International Conference on
Textures and Physical Properties of Rocks

October 13 (Wed) to 16 (Sat), 1999 in Göttingen, Germany

WORKSHOP 11:

David J. Prior (Liverpool University) & Geoffrey E. Lloyd (Leeds):

Practice and problems of applying electron backscatter diffraction (EBSD) to rock forming minerals

Workshop Aims:
To provide an open forum for discussion of current practice and problems in the application of EBSD and orientation contrast imaging to rock forming problems. The workshop will have two parts.

1. Introduction to crystallographic techniques in the SEM
This short lecture will present the theoretical background to electron diffraction and common practices in the application of EBSD and orientation contrast imaging. The lecture is aimed at potential-EBSD users who want an understanding of the basics so that the main part of the workshop is more useful.

2. Discussion of common practices and problems
The aim of this part of the workshop is to outline standard practices in a number of EBSD laboratories and to discuss common problems and potential solutions. The workshop will cover the following topics as a minimum. As the workshop is timed to follow the conference it will also be possible to discuss how EBSD practice bears upon common scientific objectives.

a. Hardware
Tilt angles
Phosphor types and position
Camera types
Sampling times
Background correction
Solid state detectors: types and positions
Charge prevention
Operating conditions

b. Sample Preparation
Polishing
Fracture/facets
Cleaning
Coating

c. Reflector files
Data sources
Structure factor calculations
Empirical modifications
Optimisation

d. Indexing
Calibration procedures
Optimising the Hough transform
Mis-indexing problems
Acceptable null data ratios
Acceptable incorrect data ratios
Manual verification procedures
Automated verification procedures
Polyphase samples: linking to X-Ray data

e. Reference frames
Sample registration procedures and errors
Common reference frame errors

f. Spatial Resolution
Imaging resolution
EBSD resolution
FEG vs. Tungsten filaments

g. Angular Resolution
Testing angular resolution
Acceptable tolerances

h. Sampling strategies
Image based
Line sampling
Grid sampling
Manual sampling
Beam and stage control
Dynamic calibration corrections
Automated intelligent sampling

i. Data Processing and Presentation
Pole figures and IPFs
ODFs
Misorientation data

j. The need for standards
Single crystal standards
Textured standards

k. Networks/ User groups

Oral contributions, posters and practical demonstrations are invited.

Return to Workshops

Last updated: Sep 6, 1999