COMPARISON OF REFLECTANCE DATA FROM VARIOUS MACERALS FROM SUB-BITUMINOUS COALS

Reflectance values were determined for selected huminite (eu-ulminite, eugelinite and phlobaphinite) and liptinite (cutinite and resinite) samples from a 560—m thick unit of lignitic-sub-bituminous coals in the Hat Creek coal deposit of British Columbia.
The objective of this study was to determine: (a) the reflectance differences between macerals, especially those of the humocollinite subgroup, and to determine the possibility of the use of the reflectance of the humocollinite maceral as an indicator of rank; (b) the trend of reflectance of humocollinite macerals (kerogen Type III) with depth; and (c) comparison of the reflectance trends of resinite and cutinite (kerogen Type II) with that of the humocollinite macerals (kerogen Type III).
Two types of corpohuminite were found in the same coal: Type 1 phlobaphinite with reflectance lower than eu-ulminite, and Type 2 phlobaphinite with reflectance higher than eu-ulminite. Reflectance of eugelinite was higher than corpohuminite and eu-ulminite.
Kerogen Type III (huminite) in these coals consists of: a) low-reflecting hydrogen-rich phlobaphinite Type 1; b) phlobaphinite Type 2 and eu-ulminite B. with intermediate reflectance and hydrogen content; c) relatively high-reflecting and perhaps hydrogen-poor eugelinite. The reflectance of all these macerals increased with depth.