YIN, PEIGUI, STEVEN W. BOESE, DONALD B. MACGOWAN, and RONALD C. SURDAM, University of Wyoming, Laramie, WY, and FRANCIS P. MIKNIS, Western Research Institute, Laramie, WY
Hydrous pyrolysis experiments were performed on samples of an immature brown coal from the Gippsland basin (southeastern Australia), for 72 hours at temperatures ranging from 270 to 350 degrees C. The produced liquid pyrolysate ("oil"), gases, and aqueous organic acid anions were quantified, and the geochemical properties of the "oil" were determined. The solid residue from experiments was studied using conventional pyrolysis, elemental analysis, vitrinite reflectance microscopy, and nuclear magnetic resonance. The maturation stages of the solid residue with increasing experimental temperatures can be correlated with maturation trends of the natural brown coal samples
in the Gippsland basin from near surface to a depth of 9000 ft. The "oil" derived from hydrous pyrolysis is poorer in saturates and richer in aromatics and NSO compounds than the natural oil produced from the Gippsland basin. The major carboxylic acid anions (e.g., acetate and propionate) generated during hydrous pyrolysis also are present within the produced waters in the Gippsland basin. The experimental results suggest that hydrous pyrolysis experiments can simulate the natural maturation of source rocks and can be used to estimate the genetic potential of specific source rock for both hydrocarbons and organic acid anions.
AAPG Search and Discovery Article #91017©1992 AAPG Rocky Mountain Section Meeting, Casper, Wyoming, September 13-16, 1992 (2009)