Unprecedented occurrence of novel C-26-C-28 21-norcholestanes and related triaromatic series in evaporitic lacustrine sediments

A novel series Of C-26-C-28 21-norcholestanes and their triaromatic analogs have been tentatively identified as major components in Eogene evaporitic sediments in Jinxian Sag of the Bohai Bay basin, northern China. These comp ounds may be viewed as representatives of a new class of molecules whose bi ological or diagenetic origin remains to be determined. Their unprecedented high abundance in the evaporitic lacustrine sediments, and related oils, s how important source and/or depositional environment controls in addition t o thermal maturity. Crown Copyright (C) 2001 Published by Elsevier Science Ltd. All rights reserved.