Structurally and tectonically, the Vorkutsk coal deposit is a large brachysynclinal fold (mulda), the long axis of which has a north-north-east strike ...

The introduction of modern complex mechanization into the practice of coal mining places high demands on the detail and reliability of forecasting of mining and geological conditions and complicating factors. Such factors at the Vorkutsk and Vorgashorsk coal fields include, first of all, small-amplitude discontinuities in coal seams with displacement of less than 10 m, which due to their parameters are not established during exploration works, so their meeting by preparatory and cleaning mine workings turns out to be in one way or another unexpected....

Within the ore field of the studied gold deposit sandy-shale deposits of the Lower Permian with thickness up to 2000 m are spread. The deposit is located in the near-axial part of a brachyanticlinal fold of meridional strike. The meridional and north-eastern and south-western breakers of the chipping type are widely developed.

The Leningrad oil shale deposit is located in the west of the Leningrad Region and is the eastern part of the Baltic oil shale basin. The industrial oil shale bed (promplast) lies in the lower part of the Kuker stratigraphic horizon of the Middle Ordovician and consists of four convergent layers of oil shale, separated by interlayers of limestone ...