CALIBRATION OF CONODONT COLOR ALTERATION USING COLOR IMAGE-ANALYSIS

A set of 40 polished sections of Silurian and Devonian conodonts with color alteration indices ranging from 1.0 to 8.0 was examined using Color Image Analysis. The color composition of each conodont specimen was determined by measuring the intensities of the red, green, and blue color components on several carefully selected areas. The data were evaluated using nested analysis of variance. The observed variance can be attributed to three different sources of error. Within the studied conodont population, the variance due to rank amounts to an average 90%. The variance due to taxonomic differences or type of conodont element is about 3% and, thus, of minor importance. The heterogeneity within single specimens amounts to 6% and is also a minor source of variance. The application of Color Image Analysis helps characterize samples of different rank but similar optical properties. Color Image Analysis helps reduce the subjectivity of conodont color alteration studies.