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Ernest P. Beroni

Publications and source records attributed to Ernest P. Beroni.

4 recordsLinked to original sources

Preliminary report on the White Canyon area, San Juan county, Utah

The White Canyon area, in the central part of San Juan County, Utah, consists of approximately two 15-minute quadrangles. Approximately 75 square miles have been mapped by the Geological Survey on a scale of 1 inch equals 1 mile, using a combined aerial photography-plane table method. Structure contours were drawn on top of the Organ Rock member of the Cutler formation. Parts of the Gonway and North Point claims, 1/4 mile east of the Happy Jack mine, were mapped in detail. The principal objectives of the investigations were: (1) to establish ore guides; (2) to select areas favorable for exploration; and (3) to map the general geology and to determine the regional relationships of the uranium deposits. The White Canyon area is comprised of sedimentary rocks of Carboniferous to Jurassic age, more than 2,000 feet thick, having a regional dip of 1° to 2° SW. The nearest igneous rocks are in the Henry Mountains about 7 miles west of the northern part of the area; The Shinarump conglomerate of the late Triassic age, the principal ore horizon in the White Canyon area, consists of lenticular beds of sandstone, conglomeratic sandstone, conglomerate, clay, and siltstone. The Shinarump conglomerate, absent in places, is as much as 75 feet thick. The sandstones locally contain molds of logs and fragments of altered volcanic ash. Some of the logs have been replaced by copper and uranium minerals and iron oxides. The clay and siltstone underlie and are interbedded with the sandstone, and are most common in channels that cut into the underlying Moenkopi formation. The Shinarump conglomerate contains reworked Moenkopi siltstone fragments, clay balls, carbonized wood, and pebbles of quarts, quartzite, and chert. Jointing is prominent in the Western part of the mapped area. The three most prominent joint trends are due east, N. 65°-75° W., and N. 65°-75° E. All joints have vertical dips. The red beds are bleached along some joints, especially those that trend N. 65°-75° W. All uranium ore produced has been from the lower part of the Shinarump conglomerate, where it commonly occurs with copper as disseminations and fracture coatings in sandstone. Uranium and copper minerals also occur in low-grade disseminated deposits in the lower Chinle and in the Moenkopi formation and in veins cutting these formations. Although some uranium deposits occur in Chinarump channels and scours, copper and uranium minerals along fractures suggest that channel control may be secondary. Logs and clay balls apparently have exerted some chemical influences for deposition. The uranium occurs as the oxide in some deposits, and as secondary hydrous sulfates, phosphates, oxides, and silicates in these and several other deposits. Charcoal, iron and manganese oxides, and veinlets of hydrocarbon are abnormally radioactive in most of the deposits. Base-metal sulfides are commonly found inside the oxidized zone. Secondary copper minerals include the hydrous sulfates and carbonate. Gangue minerals include quarts, clay minerals, and manganese oxides, dickite (?), calcite, gypsum, pyrite, and chalcedony (?). Principal wall-rock alteration appears to have been silicification, clay alteration, and bleaching. Most of the shipped ore has contained more than 0.3 percent uranium. The ore also contains copper, commonly in grades lower than 1.0 percent. Criteria believed to be most useful for prospecting for concealed uranium deposits are (1) visible uranium minerals; (2) sulfide minerals; (3) secondary copper minerals; (4) dickite (?); (5) hydrocarbons; and (6) bleaching and alteration of the Moenkopi formation.

Utah↗

Reconnaissance for trace elements in North Dakota and eastern Montana. Part 1. Geology and radioactivity. Part 2. Reserves and summary

A reconnaissance for sources of radioactive material in North Dakota and eastern Montana was made in 1948. This reconnaissance was followed by a more detailed survey of parts of Golden Valley and Slope counties, southwestern North Dakota, in June 1949. The radioactivity of representative sections of all formations known to be exposed in the area and of three manganiferous spring deposits was determined with portable Geiger-Mueller counters. At 86 localities 82 samples were taken of these formations and also of 10 ground and surface waters. Only the lignites in the upper part of the Sentinel Butte member of the Fort Union formation in the southwestern part of N. Dak. contained more than 0.005 per cent equivalent to U 3 O 8 . The ground and surface waters tested were for the most part non-radioactive. Water sample number 291 from locality 100, however, contained 0.17 parts per million U 3 O 8 . The radioactive lignites of N. Dak. appear to be limited to the higher buttes, such as Sentinel, Flat Top (Square Top), Bullion, H-T(Black), and White(Chalky) Buttes. One to five lignite beds are found in a 90-foot stratigraphic interval near the top of the Sentinel Butte member of the Fort Union formation, and from about 40 to 140 feet beneath the base of the overlying White River formation. The thickness of the beds ranges from a few inches to over six feet. The nomenclature, and therefore correct correlation, of all the beds above the middle part of the Sentinel Butte member is in doubt. The lignites and associated sand and clay beds are believed to be either equivalent to, or close to the base of, the Eocene Golden Valley formation. The exact mode of origin of the uranium in the lignite is not known. Uranium may have accumulated in swamps at the same time as the organic debris, or it may have been introduced by ground water after the formation of lignite. In either case carbon or carbon compounds apparently caused the precipitation or fixation of uranium. Further work is needed to determine the origin of this type of uranium deposit.

Montana, North Dakota↗