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Michael E. Brownfield

Publications and source records attributed to Michael E. Brownfield.

At least 19 recordsLinked to original sources

Assessment of undiscovered shale-oil and shale-gas resources in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa, 2026

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 2.4 billion barrels of shale oil and 65.4 trillion cubic feet of shale gas in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa.

Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Ba

Assessment of undiscovered conventional oil and gas resources in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa, 2026

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean conventional resources of 419 million barrels of oil and 5.5 trillion cubic feet of gas in the Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Basins of northern Africa.

Berkine, Illizi, Hamra, Murzuq, and Erdis Kufra Ba

Assessment of undiscovered oil and gas resources in the Mancos-Menefee composite and underlying Todilto Total Petroleum Systems of the San Juan Basin Province, New Mexico and Colorado, 2020

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 12 million barrels of oil and 27 trillion cubic feet of gas in the Mancos-Menefee Composite and underlying Todilto Total Petroleum Systems of the San Juan Basin Province, New Mexico and Colorado.

Colorado, New Mexico

Characterization of feed coals and coal combustion byproducts from the Wyodak-Anderson coal zone, Powder River Basin, Wyoming

The U.S. Geological Survey (USGS) determined the physical and chemical properties of more than 260 feed coal and coal combustion byproducts from two coal-fired power plants. These plants utilized a low-sulfur (0.23-0.47 wt. % S) and low ash (4.9-6.3 wt. % ash) subbituminous coal from the Wyodak-Anderson coal zone in the Tongue River Member of the Paleocene Fort Union Formation, Powder River Basin, Wyoming. Fifty-three samples of bituminous coal were collected and analyzed from a Kentucky power plant, which used several sources of bituminous coals from the Appalachian and Illinois Basins. Based on scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses of feed coal samples collected and analyzed from 1996 through the late 2000s, two mineral suites were identified: (1) a primary or detrital suite consisting of quartz (including beta-form grains), biotite, feldspar, and minor zircon; and (2) a secondary authigenic mineral suite containing alumino-phosphates (crandallite and gorceixite), kaolinite, carbonates (calcite and dolomite), quartz, anatase, barite, and pyrite. The detrital mineral suite is interpreted, in part, to be of volcanic origin, whereas the authigenic mineral suite is interpreted, in part, to be the result of the alteration of the volcanic minerals. The mineral suites have contributed to the higher amounts of barium, calcium, magnesium, phosphorus, sodium, strontium, and titanium in the Powder River Basin feed coals in comparison to eastern US coals. XRD analysis indicates that (1) fly ash is mostly aluminate glass, perovskite, lime, gehlenite, quartz, and phosphates with minor amounts of periclase, anhydrite, hematite, and spinel group minerals; and (2) bottom ash is predominantly quartz, plagioclase (albite and anorthite), pyroxene (augite and fassaite), rhodonite, and akermanite, and spinel group minerals. Microprobe and SEM analyses of fly ash samples revealed quartz, zircon, and monazite, euhedral laths of corundum with merrillite, hematite, dendritic spinels/ferrites, wollastonite, and periclase. The abundant calcium and magnesium mineral phases in the fly ash are attributed to the alteration of carbonate, clay, and phosphate minerals in the feed coal during combustion. The calcium- and magnesium-rich and alumino-phosphate mineral phases in the coal combustion byproducts can be attributed to volcanic minerals deposited in peat-forming mires. Dissolution and alteration of these detrital volcanic minerals occurred either in the peat-forming stage or during coalification and diagenesis, resulting in the authigenic mineral suite. The presence of free lime (CaO) in fly ash produced from Wyodak-Anderson coal acts as a self-contained “scrubber” for SO 3 , where CaO + SO 3 form anhydrite either during combustion or in the upper parts of the boiler. Considering the high lime content in the fly ash and the resulting hydration reactions after its contact with water, there is little evidence that major amounts of leachable metals are mobilized in the disposal or utilization of this fly ash.

Wyoming

Assessment of continuous oil and gas resources in the Mississippian Delle Phosphatic Member of the Woodman Formation in the Eastern Great Basin Province of Nevada, Utah, and Idaho, 2019

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 144 million barrels of shale oil and 559 billion cubic feet of shale gas in the Mississippian Delle Phosphatic Member of the Woodman Formation in the Eastern Great Basin Province of Nevada, Utah, and Idaho.

Nevada, Utah, Idaho