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William L. Lyke

Publications and source records attributed to William L. Lyke.

3 recordsLinked to original sources

Potentiometric surface of the Black Creek Aquifer in the central coastal plain of North Carolina, December 1986

Water level measurements were made in 95 wells open to the Black Creek aquifer at the end of 1986 to determine the configuration of its potentiometric surface over an area of about 4,900 sq mi in the central Coastal Plain of North Carolina. The altitude of the potentiometric surface of the Black Creek ranges between 80 and 100 ft above sea level along the western limit of the aquifer. From there the potentiometric surface slopes southeasterly toward a large, elongated cone of depression that has coalesced from cones that have developed around three main pumping centers and several smaller ones. The potentiometric surface in the Black Creek has declined to more than 120 ft below sea level in the southernmost cone developing near Jacksonville in Onslow County.

North Carolina

Potentiometric surface of the lower Cape Fear aquifer in the central coastal plain of North Carolina, December 1986

Water level measurements were made in four wells open to the lower Cape Fear aquifer at the end of 1986 to determine the configuration of its potentiometric surface over an area of approximately 4,100 sq mi. Because of the scarcity of data, five earlier measurements were also used to help estimate the position of the potentiometric contours. These were one-time measurements in temporary observation wells. A broad cone of depression has formed in the area between Kinston and New Bern where the potentiometric surface is below sea level and seems likely related to large groundwater withdrawals from the aquifers overlying the lower Cape Fear in that area.

North Carolina

Altitude of basement surface in the central coastal plain area of North Carolina

The altitude of the basement surface in the central Coastal Plain of North Carolina ranges from 140 ft above sea level in Wayne County near the Fall Line to 2,400 ft below sea level near the coast in Beaufort County. The slope increases to the east from about 20 ft/mi at the fall line to about 70 ft/mi at the eastern edge of the study area. The irregular nature of the basement surface is demonstrated by: (1) the variable altitudes of the basement surface in the western portion of the study area; (2) the protruding granite/gneiss rock body at a quarry near the Town of Fountain, Pitt County; and (3) the flattening of the basement surface slope observed near the Jones County and Craven County border. Basement rock types in this study area include granite, granite gneiss, metavolcanic, and metasedimentary rocks of Precambrian to Paleozoic age.

Water-Resources Investigations Report