Organic geochemistry of the Lower Cambrian Sinyaya Formation (northern slope of the Aldan anteclise)

We investigated organic matter (OM) of the Lower Cambrian Sinyaya Formation in the southeast of the Siberian Platform. The studied collection of rocks was divided into groups according to the contents of organic carbon, bitumens, and sulfur and lithologic characteristics. The content and distribution of saturated biomarkers were examined. Lanostanes C30, norlanostanes C29, 28,30-bisnorhopanes, and 2α- and 3β-methylhopanes have been identified in the bitumens. Relationships between the content of organic carbon and the distribution of hopanes, hopane ratios, and 2α-methylhopane index have been established. The conditions of sedimentation, diagenesis, and catagenesis of OM and the generation potential of the rocks have been estimated. It is shown that lanostanes, 28,30-bisnorhopanes, and methylhopanes can be used as biomarkers of the source rocks of the Sinyaya Formation and thus can help to determine the source of bitumens on the northern slope of the Aldan anteclise of the Siberian Platform.