The coal partings split into fine laminae have been first distinguished in
the clay-siliceous-carbonaceous rocks of the Upper Jurassic-Lower Cretaceou
s Bazhenov Formation in the south of the West-Siberian Plate. A petrographi
c analysis of the coal showed its sapropelic nature. Compared with the host
rock, the coal is depleted in Cd, Zn, V, and, to a lesser extent, some oth
er elements and is rich in Mo and Mn.