Fluorescent spectral types of liptinite macerals

Petrographic properties of bituminous coals collected from three Colorado basins are being investigated. These coals range in age from Late Cretaceous to Early Tertiary. Fluorescence of the liptinite macerals in these Colorado coals is known to disappear at a lower vitrinite reflectance than that observed for Carboniferous-age coals from other regions. The current investigation is concerned with characterizing selected Colorado coals with respect to maceral composition, rank, and fluorescent properties. The fluorescent spectra at a given level of coalification (rank) are being investigated and compared to those observed for other coal-bearing regions. It is hoped that, from this comparison, insight will be gained concerning the coalification history of Colorado coals. Thus, the overall objective of the project is to employ fluorescence microscopy techniques to characterize the rank relationships of the liptinite macerals from Colorado coals and to compare this work with that already completed on coals from Illinois, Oklahoma, the Appalachian regions, and Europe. Initial results are discussed.