After discoveries of large oil-and-gas fields within Yuribchen-Tokhoma Zone the Riphean deposits are considered as a promising object for an exploration. The rocks are quite widespread and probably have been deposited within several anisochronous basins. During pre-Vendian these deposits have undergone irregular erosion and deformations, which have occurred at western periphery of the platform to larger extent. This period has effaced a significant volume of Riphean sediments and has complicated their distribution as well as during this time a majority of already formed hydrocarbon accumulations have been obliterated. Source rocks are known at various levels within each basin. According to basin oil-and-gas formation modeling, the Upper Riphean source rocks had to make the biggest contribution to formation of recently present fields. Their maximum hydrocarbon generation shall be attributed to Early - Middle Paleozoic. Riphean reservoirs are placed in weathering crust of carbonates and have been formed under favourable combination of tectonic and lithological factors.