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John R. Dyni

Publications and source records attributed to John R. Dyni.

At least 19 recordsLinked to original sources

Geology and resources of some world oil-shale deposits

Oil-shale deposits are in many parts of the world. They range in age from Cambrian to Tertiary and were formed in a variety of marine, continental, and lacustrine depositional environments. The largest known deposit is in the Green River Formation in the western United States; it contains an estimated 213 billion tons of in-situ shale oil (about 1.5 trillion U.S. barrels). Total resources of a selected group of oil shale deposits in 33 countries are estimated at 409 billion tons of in-situ shale oil, which is equivalent to 2.8 trillion U.S. barrels of shale oil. These amounts are very conservative because (1) several deposits mentioned herein have not been explored sufficiently to make accurate estimates, and (2) some deposits were not included in this survey.

Book

Preliminary Stratigraphic Cross Sections of Oil Shale in the Eocene Green River Formation, Uinta Basin, Utah

Oil shale units in the Eocene Green River Formation are shown on two east-west stratigraphic sections across the Uinta Basin in northeastern Utah. Several units have potential value for recovery of shale oil, especially the Mahogany oil shale zone, which is a high grade oil shale that can be traced across most of the Uinta Basin and into the Piceance Basin in northwestern Colorado. Many thin medium to high grade oil shale beds above the Mahogany zone can also be traced for many miles across the basin. Several units below the Mahogany that have slow velocities on sonic logs may be low grade oil shale. These may have value as a source for shale gas.

Open-File Report

Geology and resources of some world oil-shale deposits

Oil-shale deposits are in many parts of the world. They range in age from Cambrian to Tertiary and were formed in a variety of marine, continental, and lacustrine depositional environments. The largest known deposit is in the Green River Formation in the western United States; it contains an estimated 213 billion tons of in-situ shale oil (about 1.5 trillion U.S. barrels). Total resources of a selected group of oil shale deposits in 33 countries are estimated at 409 billion tons of in-situ shale oil, which is equivalent to 2.8 trillion U.S. barrels of shale oil. These amounts are very conservative because (1) several deposits mentioned herein have not been explored sufficiently to make accurate estimates, and (2) some deposits were not included in this survey.

Scientific Investigations Report

Oil-shale data, cores, and samples collected by the U.S. geological survey through 1989

The U.S. Geological Survey has acquired a large collection of geotechnical data, drill cores, and crushed samples of oil shale from the Eocene Green River Formation in Colorado, Wyoming, and Utah. The data include about 250,000 shale-oil analyses from about 600 core holes. Most of the data is from Colorado where the thickest and highest-grade oil shales of the Green River Formation are found in the Piceance Creek basin. Other data on file but not yet in the computer database include hundreds of lithologic core descriptions, geophysical well logs, and mineralogical and geochemical analyses. The shale-oil analyses are being prepared for release on floppy disks for use on microcomputers. About 173,000 lineal feet of drill core of oil shale and associated rocks, as well as 100,000 crushed samples of oil shale, are stored at the Core Research Center, U.S. Geological Survey, Lakewood, Colo. These materials are available to the public for research.

Conference Paper

NORMATIVE MINERALOGY OF OIL SHALE IN THE JUHAN CORE HOLE 4-1, PICEANCE CREEK BASIN, COLORADO.

A procedure for calculating the quantities of normative minerals and kerogen in Colorado oil shale was developed and used to analyze a sequence of sodium-rich oil shales in a core hole near the depocenter of the Piceance Creek Basin in northwestern Colorado. The sequence of oil shales was found to average 48. 1 weight percent carbonate minerals, 32. 5 percent silicate minerals, 1. 9 percent pyrite, and 17. 5 percent kerogen. Dawsonite left bracket NaAl(OH)//2CO//3 right bracket and quartz are associated to a high degree in the vertical sequence, but no significant trends between mineral abundances and depth were noted.

Conference Paper

Fluorine in Colorado oil shale

Oil shale from the lower part of the Eocene Green River Formation in the Piceance Creek Basin, Colorado, averages 0.13 weight percent fluorine, which is about twice that found in common shales, but is the same as the average amount found in some oil shales from other parts of the world. Some fluorine may reside in fluorapatite; however, limited data suggest that cryolite may be quantitatively more important. Analysis of 913 samples from two core holes that penetrate the lower 375 m of the oil-shale deposits found fluorine to range from 0.001 to 2.2 weight percent; about 90 percent of the samples con tain between 0.001 and 0.20 weight percent fluorine. The analyzed sequence consists of mostly nahcolitebearing dolomitic oil shale, except for the lower 55-75 m, which consists of illitic oil shale. The fluorine content of much of the nahcolitic oil shale is somewhat lower, and much more variable from sample to sample, than that of the underlying illitic oil shale. Vertical profiles of the fluo rine content for the two core holes through the same stratigraphic interval are essentially dissimilar. The abundance of fluorine seems unrelated to shaleoil content, except in the R-5 zone and near the base of nahcolite-bearing oil shale where there is a moderate positive association. Fluorine and phos phorus abundances show mostly little or no assoc iation, and only moderate positive association in some scattered samples.

Colorado

Brief comparison of some technological and environmental aspects of large-scale surface and underground mining of oil shale, Piceance Creek Basin, Colorado

Comparison of several aspects of surface and underground methods of mining for large-scale oil shale extraction in the Piceance Creek Basin suggests that surface mining techniques may have several advantages over underground methods. For a production level of one million barrels of shale oil per day, potential advantages include those related to economics, environmental effects, and the overall national interest. One million barrels of shale oil per day could be produced from 2-3 large surface mines compared to perhaps 10-20 large underground mines. Fewer surface mines would result in: (1) fewer roads and utility corridors, (2) less acres disturbed per barrel of oil pro duced, (3) reduced detrimental effects on ground water and surface water, (4) less wildlife distur bance, (5) a safer overall operation, (6) a greater opportunity to achieve stable long-term land and water reclamation, (7) potential economic advantages related to scale and materials handling, and (8) a three- to five-fold increase in resource recovery. Advantages to underground (including modified in situ [MIS]) mines include: (1) more flexibility of mine siting, (2) mining and handling a minimum of waste rock, and (3) simplified ore grade control for processing.

Colorado

Distribution and origin of sulfur in Colorado oil shale

The sulfur content of 1,225 samples of Green River oil shale from two core holes in the Piceance Creek Basin, Colorado, ranges from nearly 0 to 4.9 weight percent. In one core hole, the average sulfur content of a sequence of oil shale 555 m thick, which represents nearly the maximum thickness of oil shale in the basin, is 0.76 weight percent. The vertical distribution of sulfur through the oil shale is cyclic. As many as 25 sulfur cycles have lateral continuity and can be traced between the core holes. Most of the sulfur resides in iron sulfides (pyrite, marcasite, and minor? pyrrhotite), and small amounts are organically bound in kerogen. In general, the concentration of sulfur correlates moderately with shale-oil yield, but the degree of association ranges from quite high in the upper 90 m of the oil -shale sequence to low or none in the leached zone and in illitic oil shale in the lower part of the sequence. Sulfur also correlates moderately with iron in the carbonate oil -shale sequence, but no correlation was found in the illitic samples. Sulfide mineralization is believed to have occurred during early and late stages of diagenesis, and after lithification, during development of the leached zone. Significant amounts of iron found in ankeritic dolomite and in illite probably account for the lack of a strong correlation between sulfur and iron.

Colorado

Nahcolite analyses of seven drill cores from the saline facies of the Green River Formation in Northwest Colorado

This report presents the results of about 3,060 quantitative analyses for nahcolite in cores from seven holes drilled in the saline facies of the Green River Formation (Eocene) in Rio Blanco County, Colorado. Nahcolite analyses of three additional drill cores from the same area were reported earlier by Dyni, Beck, and Mountjoy (1971). The analyses of these 10 drill cores were made during a detailed stratigraphic and resource study of the nahcolite that is found in association with the oil-shale deposits of the Green River Formation in the Piceance Creek basin (Dyni, 1973). The locations of the drill holes are shown on figure 1 and are described in the table headings.

Colorado