Dolomite Green River formation

The Wyoming deposits of Green River Formation oil shale received different stratigraphic names, but they show some striking similarities to the distribution in Colorado (9). The bottom section called the Tipton Shale Member is predominately clay-rich oil shale similar to that in Colorado. The next section, called the Wilkins Peak Member, contains dolomite-rich oil shale layers interspersed with layers of saline minerals, particularly trona, or with clastic deposits away from the depositional centers. The uppermost section, called the Laney Member, consists of dolomite-rich deposits formed during a reexpansion of ancient Gosuite Lake. 

River Formation of Eocene age Dolomitic oil shale of the Green River Formation (80)... 

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