EXTENDED TRICYCLIC TERPANES IN SEDIMENTS AND PETROLEUMS

An extended series of tricyclic terpanes was identified in sediments a nd petroleums from Brazil. The identification of the tricyclic terpane s was based on their chromatographic behavior and characteristic MS/MS transitions from molecular ions to m/z 191. We identified tricyclic t erpane homologs up to C54. The presence of this extended series, from C19 up to C54, varies considerably with depositional environment, bein g prominent in saline lacustrine and marine carbonate settings. This s uggests that the biological precursor organism lived in moderate condi tions of salinity.