Geology topics

Research about New Jersey;Pennsylvania

Source-linked reports with geographic coverage including New Jersey;Pennsylvania.

3 recordsLinked to original sources

USGS2000

Relationship of Eastern hemlock ( Tsuga canadensis ) to the ecology of small streams in Delaware Water Gap National Recreation Area

Hemlock ravines in Delaware Water Gap National Recreation Area (DEWA) are highly valued because of their distinctive aesthetic, recreational and ecological qualities. We conducted a comparative study designed to determine the potential long-term consequences to aquatic communities of the suspected transition from hemlock-dominated forests to mixed hardwood forests as a result of hemlock woolly adelgid (HWA; Adelges tsugae) induced mortality. A landscape analysis of DEWA using Geographic Information Systems (GIs) was used to select 14 hemlock and hardwood site-pairs that were similar in topography (i.e., slope, terrain shape, aspect, light levels) and stream size (first or second order) but differed in forest composition. This paired watershed approach provided a powerful means to discern the influence of hemlock forests on stream communities. This study was designed to provide an aquatic perspective on potential losses of biological diversity should hemlock forests die.

New Jersey;Pennsylvania↗

USGS1954

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↗

USGS1954

Chemical characteristics of Delaware River water, Trenton, New Jersey, to Marcus Hook, Pennsylvania

This progress report gives the results of an investigation of the quality of water in the Delaware River from Trenton, N. J. to Marcus Hook, Pa., for the period August 1949 to December 1952. The Delaware River is the principal source of water for the many industries and municipal water supplies along this reach of the river and both industries and municipalities use it for the disposal of their wastes. Consequently, a study of the quality of the water and variations in the quality caused by changes in streamflow, tidal effects, pollution and other factors is important to the many users. In both New Jersey and Pennsylvania steps are being taken to abate pollution, thus it is of more than passing interest to measure the effects of waste treatment on the quality of the Delaware River water. At average or higher rates of streamflow the mineral content of the water increases slightly from Trenton to Marcus Hook. There is little variation in the concentration of dissolved minerals from bank to bank or from top to bottom of the river. At times of protracted low rates of flow the effect of ocean water mixing with the river water may be noted as far upstream as Philadelphia. At such times the salinity is often greater near the bottom of the river than near the top. The increase in chloride concentration upstream from Philadelphia is small compared to the rapid increase downstream from Philadelphia. Temperatures of offshore water vary with the season, but on a given day are substantially uniform throughout the reach of the river from Trenton to Marcus Hook. The water contains less dissolved oxygen as it flows downstream indicating that oxygen is being consumed by oxidizable matter. From Philadelphia downstream there are periods, especially in late summer, when the dissolved oxygen is barely sufficient to meet the oxygen demands of the pollution load.

New Jersey;Pennsylvania↗