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Research about New Jersey

Source-linked reports with geographic coverage including New Jersey.

At least 505 records · Page 28Linked to original sources
USGS1958

Geology and magnetite deposits of Dover district, Morris County, New Jersey, with a description of the geologic section at Hibernia mine

The Dover district, Morris County, N. J., one of the oldest mining regions in the United States, has been active intermittently since the early part of the 18th century, and has yielded in excess of 26 million long tons of iron ore valued at more than $100,000,000. This is about 70 percent of the total production of iron ore from the State of New Jersey. Since 1940 about 500,000 tons of magnetite lump ore and fine concentrate have been shipped annually from the Scrub Oaks, Richard, and Mount Hope mines—the 3 producing mines in the district.

New Jersey↗
USGS1954

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↗
USGS1951

Preliminary report on the geology and ground-water supply of the Newark, New Jersey, area

In the Newark area, ground water is used chiefly for industrial cooling, air-conditioning, general processing, and for sanitary purposes. A small amount is used in the manufacture of beverages. Total ground-water pumpage in Newark is estimated at not less than 20,000,000 gallons daily. The Newark area is underlain by formations of Recent, Pleistocene and Triassic age, and the geology and hydrologic properties of these formations are discussed. Attention is called to the important influence of a buried valley in the rock floor beneath the Newark area on the yield of wells located within it. Data on the fluctuation of the water levels and the variation in pumpage are presented, and their significance discussed. The results of a pumping test made during the investigation were inconclusive. The beneficial results of artificially recharging the aquifers in one part of the area are described. The intrusion of salt water into certain parts of the ground-water body is described and graphically portrayed by a map showing the chloride concentration of the ground water in various parts of the City. Insofar as available data permit, the chemical quality of the ground water is discussed and records are given of the ground-water temperatures in various parts of the City. There has been marked lowering of the water table in the eastern part of the area, accompanied by salt water intrusion, indicating that the safe yield of the formations in this part of Newark has probably been exceeded. It is recommended that the study of the ground-water resources of this area be continued, and that artificial recharging of the aquifers be increased over as wide an area as possible.

New Jersey↗
USGS1950

Geology of the Dover magnetite district, New Jersey

This report has been prepared with two purposes in mind - to provide a better understanding of the magnetite deposits of the district and to present detailed petrologic and structural information that will aid in an understanding of the geology of the crystalline Highlands of Jew Jersey and adjacent states.

New Jersey↗