Application of Geographical Information Systems to shape-fabric analysis

Abstract A Geographical Information System (GIS) has been applied to shape-fabric analysis and strain measurement. It works in either raster or vectorial format, allows determination of many geometrical features of grains and stores additional descriptive information linked to all these graphic elements. Some new applications for shape characterization and strain measurement have been developed, e.g. the shape parameter S, the Fry method installed as a variant that uses only contiguous grains (TFry method) and a new method (ASPAS method), based on the intersection lengths of the lines of a radial network with the grain boundaries. A compilation of finite-strain estimates on a tectonite sample has been used to compare the results obtained by the new methods. As the shape fabric does not register the full strain history, the strain ratios obtained from the shape-fabric analysis are lower in most cases than those obtained using pretectonic markers.

[1]  D. Dunnet,et al.  A technique of finite strain analysis using elliptical particles , 1969 .

[2]  F. Bastida,et al.  Conodont colour alteration indices (CAI) of Upper Ordovician limestones from the Iberian Peninsula , 1998 .

[3]  M. R. Johnson.  Structural geology , 1977, Nature.

[4]  R. Panozzo.  Two-dimensional strain from the orientation of lines in a plane , 1984 .

[5]  R. Panozzo.  Two-dimensional strain determination by the inverse Surfor wheel , 1987 .

[6]  G. Thomas.  Elements of calculus and analytic geometry , 1976 .

[7]  Dana Prescott Bartlett.  General Principles of the Method of Least Squares , 2006 .

[8]  E. Erslev.  Normalized center-to-center strain analysis of packed aggregates , 1988 .

[9]  H. Exner.  Analysis of Grain- and Particle-Size Distributions in Metallic Materials , 1972 .

[10]  Teresa Connolly,et al.  Understanding GIS; The ARC/INFO Method (PC Version) , 1998 .

[11]  Renée Heilbronner,et al.  The autocorrelation function: an image processing tool for fabric analysis , 1992 .

[12]  Renée Heilbronner,et al.  Integrated spatial and orientation analysis of quartz c-axes by computer-aided microscopy , 1993 .

[13]  G. Draper.  Geological strain analysis—a manual for the Rf/φ technique: by Richard J. Lisle. Pergamon Press, Oxford, 1985, viii + 99 pp. $15 hard cover/$8.95 soft cover , 1986 .

[14]  J. Ramsay.  Folding and fracturing of rocks , 1967 .

[15]  N. Fry.  Random point distributions and strain measurement in rocks , 1979 .

[16]  T. Masuda,et al.  Fractal analysis of experimentally, dynamically recrystallized quartz grains and its possible application as a strain rate meter , 1998 .

[17]  Andrew R. H. Swan,et al.  Image analysis of petrographic textures and fabrics using semivariance , 1995, Mineralogical Magazine.

[18]  R. Panozzo.  Two-dimensional analysis of shape-fabric using projections of digitized lines in a plane , 1983 .

[19]  M. McNaught.  Modifying the normalized fry method for aggregates of non-elliptical grains , 1994 .

[20]  Patrick Launeau,et al.  Fabric analysis using the intercept method , 1996 .

[21]  Kieran F. Mulchrone.  Application of Delaunay triangulation to the nearest neighbour method of strain analysis , 2003 .

[22]  B. Sander.  Einführung in die Gefügekunde der geologischen Körper. In zwei Teilen. 2. Teil: Die Korngefüge. Springer-Verlag. Wien und Innsbruck 1950. XII + 409 s., 153 fig., 166 Gefüge-diagram, 8 pl., därav 4 i färgtryck. Pris $ 15: 30 , 1951 .

[23]  Eric A. Erslev,et al.  Least-squares center-to-center and mean object ellipse fabric analysis , 1990 .

[24]  R. Heilbronner.  Automatic grain boundary detection and grain size analysis using polarization micrographs or orientation images , 2000 .

[25]  R. Lisle.  Strain analysis using deformed pebbles: The influence of initial pebble shape , 1979 .

[26]  J. H. Kruhl,et al.  The fractal shape of sutured quartz grain boundaries: application as a geothermometer , 1996 .