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James Pierson Minard

Publications and source records attributed to James Pierson Minard.

13 recordsLinked to original sources
USGS1980

Geology of the Round Bay quadrangle, Anne Arundel County, Maryland

Six Coastal Plain formations and one group crop out in the Round Bay quadrangle near the inner edge of the Atlantic Coastal Plain physiographic province. The quadrangle lies astride the Severn River, in Anne Arundel County, near Annapolis, Md. The seven stratigraphic units aggregate as much as 128 m in outcrop. In ascending order, the units are: the upper part of the Potomac Group and the Magothy, Matawan, and Severn Formations, all of Cretaceous age; the Brightseat and Aquia Formations of Paleocene age and the Calvert Formation of Miocene age. Quaternary deposits are thin and cover only small areas; they are all mapped under one unit. Several small, thin deposits of Tertiary alluvium are mapped separately. The largely unconsolidated Cretaceous and Tertiary formations consist chiefly of quartz, glauconite, clays, muscovite, chlorite, lignite, feldspar, and pyrite. Quaternary sediments are mostly locally derived sands, silts, and clays with some gravel and, in the finer sediments, considerable amounts of organic matter. The Cretaceous and Tertiary units strike generally northeast; the younger the formation, the more easterly it strikes. Dips are gentle, 3.6 to 15 m per kilometer toward the southeast, and decrease upward through the section. The Round Bay quadrangle is near the southern limit of several formations that thin progressively toward the southwest from New Jersey. Some pinch out between Betterton, on the eastern shore of Chesapeake Bay, and Round Bay, on the western shore, whereas others are present only as thin remnants 1-2 m thick. Resources of the quadrangle include abundant ground water, sand, and high land values near water.

Maryland↗
USGS1979

Upper Cenozoic sediments of the lower Delaware Valley and the northern Delmarva Peninsula, New Jersey, Pennsylvania, Delaware, and Maryland

The 'yellow gravels' referred to by R. D. Salisbury in 1898 and the 'Trenton gravel,' as defined by H. C. Lewis in 1880, were investigated along the inner edge of the New Jersey Coastal Plain in southern New Jersey and in the northern Delmarva Peninsula. The highest level deposits, the Beacon Hill gravel, are found on only the highest hills in the New Jersey Coastal Plain. Their distribution suggests deposition from north to south across the plain. After deposition of the Beacon Hill, probably in middle or late Miocene time, a narrow valley was formed paralleling the inner edge of the New Jersey Coastal Plain between Raritan Bay and Camden. South of Camden, the valley broadened, covering much of southern New Jersey. The deposits in this valley are largely the Bridgeton Formation as we have redefined it. A second narrow valley was entrenched through the Bridgeton between Trenton and Salem, N.J. This valley broadens and covers much of the northern Delmarva Peninsula west of the Delaware River. The fill in the valley is largely the Pensauken Formation, as we have redefined it in our report. Collectively, the Beacon Hill, the Bridgeton, and the Pensauken were originally the 'yellow gravels' of Salisbury. These deposits are all fluviatile in origin and were largely formed as a series of step like downcutting channels. The Delaware Valley between Trenton and the lower Delaware Bay region is occupied by the 'Trenton gravel,' which is below the average level of the 'yellow gravels.' Two units recognized throughout the area and informally named the Spring Lake beds and the Van Sciver Lake beds are lithologically distinct from the 'yellow gravel' formations. The lithologies of the Spring Lake beds and the Van Sciver Lake beds are much more heterogeneous than those of the older formations. These two units, particularly, contain much greater amounts of silt and clay, often in thick beds. The depositional environments associated with the two units include fluviatile, estuarine, and marginal marine. Both these units are interpreted to be late Pleistocene (Sangamonian) in age.

Delaware, Maryland, New Jersey, Pennsylvania↗
USGS1957

Photogeologic maps of the Miles Ranch and Love Ranch quadrangles, Fremont and Natrona Counties, Wyoming

Love Ranch and Miles Ranch quadrangles are in the Wind River Basin, Wyoming (fig. 1). The rocks exposed in the quadrangles are sedimentary, and range in age from Late Cretaceous to early Tertiary. The youngest formation in the quadrangles, the Wind River formation of Eocene age, is uranium bearing in adjacent areas. Within the two quadrangles the Wind River formation unconformably overlies all the older rocks. In Miles Ranch quadrangle the Wind River formation is divided, on the basis of photointerpretation, into an upper and lower unit; the relationship of these units to units of the Wind River formation, as mapped in adjoining areas, has not been determined.

Trace Elements Memorandum↗