Green River Shale/Formation

These oil shales represent two trillion barrels of oil in Colorado, Utah, and Wyoming, and an additional one trillion barrels of oil of Devonian shale formation in the eastern United States. Eastern Devonian shale is quite different from western Green River shale. The noticeable differences are in geological age, kerogen structure, oil content, pyrite, and other mineral compositions. In the past, little effort has been focused on Devonian shales. However, the increasing role of eastern shales has now... 

Methane. The methane evolution profiles for all five shale samples are surprisingly similar, but occur at significantly higher temperatures than has been observed (2) for the Green River shale. Although some methane evolution accompanies the oil formation, the major part is formed in the secondary pyrolysis region. At least three major processes with maxima in the vicinity of 500, 580 and 700°C appear to contribute to the total methane formation. Activation energies for these processes were determined for Condor carbonaceous shale and are summarised in Table 6. 

Carbon Monoxide. All shale samples showed a significant peak in the Co evolution rates in the temperature range over which oil evolution occurs. At these relatively low temperatures, it is unlikely that the reaction between CO2 and residual char could be a significant source of carbon monoxide (2), and it appears that for these shales and in contrast to the Green River shale (2), the decomposition of the kerogen results in the formation of CO. In the case of the Stuart shale, the processes leading to the formation of the CO in the low temperature range are characterised by a mean activation of n/ 174 kJ mo 1-1 and a distribution of 11 kJ mol-1 (Table 6). 

Upon exposure of the shales to liquid SO2, highly colored solutions develop due to formation of donor-acceptor complexes between extracted oil constituents and the SO2. Green River shale produces red-brown solutions, Moroccan shale forms orange solutions, and Antrim shale forms yellow solutions in each case, these colors are more intense when higher processing temperatures are used. 

Estimates of oil shale deposits by continent are given in Table 1 (2). Characteristics of many of the world s best known oil shales are summarized in Table 2 (3,4). Oil shale deposits in the United States occur over a wide area (Table 3). The most extensive deposits, covering ca 647,000 km (250,000 mi ), are the Devonian-Mississippian shales of the eastern United States (5). The richest U.S. oil shales are in the Green River formation of Colorado, Utah, and Wyoming. Typical mineral and organic analyses for Green River oil shale are given in Table 4. 

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...

Desborough, G. A. 1978. A biogenic-chemical stratified lake model for the origin of oil shale of the Green River Formation An alternative to the playa-lake model. Geological Society of America Bulletin, 89, 961-971. 

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. 

Fig. 1. Distribution of oil shale in the Green River formation. (U.S. Geological Survey)...

Work on the production of petroleum-like materials from oil shale in the Green River formation dates back many years. One of the first major efforts was that undertaken by the U.S. Bureau of Mines in 1944. This program involved two 40-ton capacity retorts that operated between 1947 and 1951, with a production of some 920 runs and a total consumption of 37,500 tons of raw shale. This was a batch process and much was learned from this experience. 

The literature on oil shale and shale oils is much richer and goes back several decades. However, because of its size and location, most of the literature deals only with one oil shale formation—the Green River Formation. 

J oil shale more than 10 ft thick Area of Green River Formation... 

Purpose. This fracturing program was intended to devise an effective method to fracture the formation with wellbore shots. More specifically, Green River site 1 was developed to test chemical explosive fracturing procedures for establishing communication between wells at greater depths and well spacings than had been previously attempted in oil shale. 

Case Studies. The discussion of individual studies in this paper are intended as brief summaries of important results from a variety of ancient and modern lake sediments discussed in other papers (13-16). These studies include two Paleogene lacustrine oil shales—the Green River Formation (Colorado, Utah, and Wyoming) and the Rundle Formation (Queensland, Australia). The locations of these formations are shown in Figure 3, and key characteristics of the deposits are compared in Table I. Also included are results from studies of three modern productive saline lakes (Soap Lake, Washington Great Salt Lake, Utah and Walker Lake, Nevada) and two... 

Table I. Comparison of characteristics of oil-shale deposits of the Green River and Rundle Formations...

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