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Frederick K. Mack

Publications and source records attributed to Frederick K. Mack.

At least 19 recordsLinked to original sources
USGS1999

Potentiometric surface of the upper Patapsco aquifer in southern Maryland, September 1997

This report presents a map showing the potentiometric surface of the Upper Patapsco aquifer in the Patapsco Formation of Cretaceous age in Southern Maryland during September 1997. The map was prepared from water-level measurements in 42 wells. The potentiometric surface was 122 feet above sea level near the northern boundary and outcrop area of the aquifer in a topographically high area of Anne Arundel County, and 57 feet above sea level in a similar setting in Prince Georges County. From these high areas, the potentiometric surface declined to the southeast toward large well fields in the Annapolis area and Arnold and from all directions toward a cone of depression southwest of Waldorf. Ground-water levels reached 20 feet below sea level in the Annapolis area, 28 feet below sea level at Arnold, and 118 feet below sea level southwest of Waldorf.

Maryland↗
USGS1999

The difference between the potentiometric surfaces of the upper Patapsco aquifer, September 1990 and September 1997 in southern Maryland

This report presents a map that shows the change in the potentiometric surface of the Upper Patapsco aquifer in the Upper Patapsco Formation of Cretaceous age in Southern Maryland for September 1990 and September 1997. The map, based on water-level measurements in 38 wells, shows that the change of the potentiometric surface during the 7-year period ranged from zero in the most northern part of the study area, which is near the outcrop of the aquifer, to a decline of 19 feet at LaPlata, which is near the most southwestern part of the study area.

Maryland↗
USGS1999

The difference between the potentiometric surfaces of the lower Patapsco Aquifer, September 1990 and September 1997 in southern Maryland

This report presents a map that shows the change in the potentiometric surface of the Lower Patapsco aquifer in the Lower Patapsco Formation of Cretaceous age in Southern Maryland for September 1990 and September 1997. The map, based on water-level measurements in 53 wells, shows that the change of the potentiometric surface during the 7-year period ranged from rises of 8 feet at Indian Head and 1 foot near the outcrop area in Glen Burnie to declines of 39 feet at Arnold, 37 feet at Waldorf, and 37 feet at Morgantown.

Maryland↗
USGS1997

Potentiometric Surface of the Aquia Aquifer in southern Maryland, September 1995

A map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in southern Maryland during September 1995 was prepared from water-level measurements in 80 wells. The potentiometric surface was above sea level near the northwestern boundary and outcrop area of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties, and was below sea level in the remainder of the study area. The hydraulic gradient was directed southeastward toward an extensive cone of depression around well fields at Lexington Park and Solomons Island. Ground-water levels were more than 70 feet below sea level in a 60-square-mile area surrounding the deepest part of the cone of depression and 126 feet below sea level in one well near the center of the cone.

Open-File Report↗
USGS1996

Potentiometric Surface of the Magothy Aquifer in Southern Maryland, September 1995

A map showing the potentiometric surface of the Magothy aquifer in the Magothy Formation of Cretaceous age in southern Maryland during September 1995 was prepared from water-level measurements in 92 wells. The potentiometric surface was highest near the northwestern boundaryand outcrop area of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties. Regionally, the potentiometric surface sloped gently downward towards the southeast and the local gradients were directed toward the centers of three cones of depression that have developed in response to pumping. These cones were centeredaround well fields in the Annapolis, Waldorf, and Chalk Point areas. Ground-water levels were as low as 63 feet below sea level in the Waldorf area, more than 50 feet below sea level at Chalk Point, and almost 20 feet below sea level near Annapolis.

Open-File Report↗