Predicting zones of separate oil and gas accumulation in lower-middle Cambrian Kuonamsky and Inikansky deposits of Eastern Siberia

The Kuonamsky bituminous siliceous-carbonate shale formation occurring in the northern and eastern parts of the Siberian Platform and its Early-Middle Cambrian analogues are the objects of this research. The Kuonamsky Formation contains the Inikansky, Shumninsky deposits and their age analogues present in the northern and eastern regions of the Siberian Platform. With the purpose of petroleum exploration, geochemical characteristics of the Organic Matter from the comprehensive collection of the samples of Kuonamsky siliceous-carbonate rocks taken from the regions of the Anabarsky and Aldansky anteclises and Vilyuisky hemisyneclise are discussed in the paper. On the basis of geochemical studies and generalization of the available actual data, high quality of source rocks in Lower-Middle Cambrian Kuonamsky and Inikansky formations of the Eastern Siberia are confirmed, and locations of hydrocarbon gas and oil accumulation zones in the area of studied formations occurrence are also predicted for the first time. It is found that owing to heat and mass transfer media moving up the fault zones, to thermal maturity of Organic Matter increases up to oil window both towards the Vilyuisky hemisyneclise and eastern part of the Aldansky anteclise to the boundary with the Mesozoic zone of folding