DETERMINATION OF COAL MACERAL COMPOSITION BY MEANS OF COLOR IMAGE-ANALYSIS

With the development of Colour Image Analysis Systems (CIAS) which are capable of processing multi-colour images it has become possible to d efine more complex optical units in comparison to black and white imag e analysis systems. The colour composition of each maceral group can b e defined by intensity levels of three different colours, i.e. red, gr een, blue, thus allowing the user to characterise macerals within smal l diagnostic thresholds. This investigation presents the results of th e application of CIAS (Cue 3, Olympus) to coal petrology. Maceral grou p analyses have been carried out on a series of 7 high to medium volat ile bituminous coals from the Carboniferous Coal Measures of The Nethe rlands, using both conventional point count analysis (PCA) and CIAS. T he results show that CIAS is applicable to maceral group analysis of c oals of different ranks. CIAS is time efficient as compared to PCA.