Cyclic diaryl ethers in a Late Permian sediment

Abundant cyclic diaryl ethers, such as dibenzofuran and its alkyl derivativ es are found in solvent extracts and kerogen pyrolysates of a Late Permian organic-rich marl from northern Italy. These organic compounds are distingu ishable from biphenyl and its alkyl derivatives by high resolution GC-MS. B ulk geochemical (Rock-Eval) and transmitted/reflected light microscopic ana lyses indicate that the dominant source of organic matter in the sediment i s from partially decomposed land plant debris which has been transported in to the marine depositional setting. A likely origin for the cyclic diaryl e ther moieties is dehydrated and condensed polysaccharides. Possible sources for the polysaccharides are the organic constituents of land plants, micro bes and fungi. (C) 1999 Elsevier Science Ltd. All rights reserved.