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Organic geochemical studies of the transformation of gymnospermous xylem during peatification and coalification to subbituminous coal

January 1, 1990

Organic geochemical investigations of peatified and coalified xylem from gymnosperms have provided useful information on the organic transformational processes collectively known as coalification. The combined use of solid-state 13C nuclear magnetic resonance (NMR) and pyrolysis/gas chromatography/mass spectrometry (py/gc/ms) has allowed us to examine the organic composition of peatified and coalified xylem on both a bulk (average) compositional basis and on a detailed molecular basis. We conclude from our studies that coalification of gymnospermous xylem involves the following processes1.

(1) early selective removal of cellulosic materials so that lignin, a primary constituent of xylem, is transformed to macromolecular aromatic components in coal;2.

(2) modification of gymnospermous lignin by demethylation to form catechol-like structures, and by condensation reactions to induce a high level of cross-linking at an early stage of coalification; and

(3) dehydroxylation during increasing coalification to subbituminous coal, the resultant xylem becomes more phenolic in character as the catechol-like structures decrease.


Publication Year 1990
Title Organic geochemical studies of the transformation of gymnospermous xylem during peatification and coalification to subbituminous coal
DOI 10.1016/0166-5162(89)90090-6
Authors Patrick G. Hatcher, H. E. Lerch, T.V. Verheyen
Publication Type Article
Publication Subtype Journal Article
Series Title International Journal of Coal Geology
Index ID 70016453
Record Source USGS Publications Warehouse