POLAR CONSTITUENTS OF ORGANIC-MATTER RICH MARLS FROM EVAPORITIC SERIES OF THE MULHOUSE BASIN

A suite of marl samples from the evaporitic series of the Mulhouse bas in (France; Lower Oligocene) was studied for its biomarker content, in particular its polar constituents. Novel series of 3-carboxyalkyl ste ranes and 15-oxo triaromatic ketones were identified by synthesis. The 3-carboxyalkyl steranes probably originate from highly polar precurso rs yet unreported in living organisms. Our data suggest that micro-alg ae could be the major source of these compounds which seem to be indic ators of high algal input rather than characteristic of evaporitic env ironments. The 15-oxo triaromatic ketones could be oxidation products of triaromatic steroid hydrocarbons formed during diagenesis, although their formation during work-up procedure could not be excluded.