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P.W. Choquette

Publications and source records attributed to P.W. Choquette.

2 recordsLinked to original sources

Occurrences of uranium at Clinton, Hunterdon County, New Jersey

An occurrence of uranium at Clinton, Hunterdon County, N. J. was first brought to the attention of the U.S. Geological Survey when Mr. Thomas L. Eak of Avenel, N. J. submitted to the Survey a sample containing 0.068 percent uranium. Subsequent examinations of the area around Clinton indicated that detailed mapping and study were warranted. The uranium occurrences at Clinton are in or associated with fault zones in the Kittatinny limestone of Cambro-Ordovician age. The limestone generally light gray, thick bedded, and dolomitic; chert is common but not abundant. Regionally and locally, faults are the most significant structural features. The local faults at Clinton are the loci for most of the uranium. The largest fault can be traced for about 700 feet and is radioactive everywhere it crops out. Samples from this fault contain as much as 0.038 percent uranium; the average content is about 0.010 percent uranium. Uranium also occurs disseminated in two 4-inch layers of black feldspathic dolomite and in several zones of residual soil derived from the Kittatinny limestone. The black layers contain as much as 0.046 percent uranium and can be traced only about 20 feet along strike. They are cut by a small fault that is also radioactive. The radioactive soil zones are roughly elongated parallel to bedding. Soil from them contains up to 0.008 percent uranium. The uranium occurrences are best explained by a supergene origin. The sampling, mapping, and radioactivity testing of uranium occurrences at Clinton indicate they are too low grade to be of current economic interest.

New Jersey

Uranium occurrences in Bucks County, Pennsylvania, and Hunterdon County, New Jersey

Eleven occurrences of uraniferous argillite in the Lockatong lithofacies and five occurrences of uraniferous sandstone in the Stockton lithofacies, both of Triassic age, are known in Buck County, Pa. and Hunterdon County, N.J. Most of the occurrences were discovered by the Geological Survey, though prospectors found several. The Delaware quarry, Bucks County, Pa., was mapped and sampled in detail because the best exposed and most uraniferous argillite known crops out there. Sketches of two sandstone occurrences were made. Two stratigraphic sections of part of the Stockton formation were made in an unsuccessful effort to find key beds to which the uranium occurrences might be referred. The argillite occurrences contain as much as 0.034 percent uranium but commonly contain only about 0.010 percent uranium. They are known to extend for several hundred feet along the strike and may possibly extend several thousand feet, but less than a mile. They range from about 1 to 6 feet in thickness. The sandstone occurrences are characterized by the presence of pyrite or limonite and the alteration of feldspar to clay. The most uraniferous parts of the sandstone contain mud pebbles or lenses. The sandstone with mud pellets generally contain from 0.01 to 0.03 percent uranium, but selected parts of the pellets contain as much as 0.29 percent uranium. The known occurrences are small, about 1 to 2 feet thick and 20 to 30 feet long. None of the argillite or sandstone occurrences are now of economic importance.

New Jersey;Pennsylvania