Oil and gas potential of ancient Riphean sediments of the East European Platform (Mezen syneclise) based on basin analysis

Oil and gas reservoirs of ancient sediments is one of the critical areas of increasing hydrocarbon resources. The study area located in the European part of the north-east of the East European Platform, characterized by extremely low and uneven geological and geophysical knowledge, has repeatedly attracted attention as an area with ambiguous prospects for oil and gas content. Repeated attempts have been made to estimate the local oil and gas potential using the information, methods and technologies available in all those years. Seismic exploration works in 2010–2011 in the White Sea water area, where an extension of a series of tectonic structures from land—ancient rifts of the Mezen syneclise—was revealed, and processing of drilling logs from Middle Nyafta well 21 allowed a more systematic view of the structure of the ancient Riphean age strata and, with regard to earlier research analyses and generalizations, enabled an attempt to assess the oil and gas prospects using modern technologies of basin modeling. The main distinctive feature of the Mezen syneclise is the three-layer structure of the sedimentary cover, consisting of synrift, syneclise and plate complexes. The sedimentary cover is composed of the Upper Proterozoic (Middle and Upper Riphean), Vendian–Cambrian and Paleozoic rocks. In general, while the thickness of the Vendian–Cambrian and Paleozoic sediments is small and the oil and gas potential of these sediments is estimated to be extremely low, the thickness of the Middle Upper Riphean sediments is 3–5 km onshore and reaches 6 and more kilometers in the water area, which makes it possible to assess them as an independent area of study.