Green River formation Mahogany zone

Table 8. Elemental concent rations determined in raw (i.e., feedstock). retorted. and after low-temperature ash (LTA) of oil shale from Green River Formation. Mahogany Zone, (GRFMZ). USA...

Saether, O. M., Runnells, D. D., Ristinen, R. A. Smythe, W. 1981. Fluorine its mineralogical residence in oil shales of the Mahogany Zone of the Green River Formation, Piceance Creek Basin, Colorado, USA. Chemical Geology, 31, 169-184. 

Inorganic Geochemistry of Mahogany Zone Oil Shale in Two Cores from the Green River Formation... 

In northwest Colorado, the Parachute Creek Member of the lacustrine Green River Formation (Eocene) contains thick sequences of rich oil shale that were deposited in ancient lake Uinta. The richest sequence and the richest oil-shale bed within the Parachute Creek Member are called the Mahogany zone... 

The Mahogany zone of the Green River Formation is rich in carbonate-related elements and poor in most trace elements compared to an average shale or average black shale. The two cores have similar chemistry, although CR-2 samples have more Ca, Cu, La, Ni, Sc, and Zr and 01-A samples have more As and Sr. These differences probably reflect slight differences in depositional conditions, sediment source areas, or diagenesis. 

Oil shale core samples were available from two widely separated (East, West) locations in the Green River formation (Figure 1). The first core studied was from the Geokinetics site south of Vernal, Utah. In this area the Mahogany zone is close... 

Table I Bulk mineralogy of Green River formation C a Tract, Mahogany Zone, oil shale in weight percent...

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