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Frederick K. Mack

Publications and source records attributed to Frederick K. Mack.

At least 37 records · Page 2Linked to original sources
USGS1996

Potentiometric Surface of the Lower Patapsco Aquifer in Southern Maryland, September 1995

A map showing the potentiometric surface of the lower Patapsco aquifer in the Patapsco Formation of Cretaceous age in southern Maryland during September 1995 was prepared from water-level measurements in 69 wells. The potentiometric surface was 87 feet above sea level near the northwestern boundary and outcrop area of the aquifer in topographically high areas of Anne Arundel County. From this high area, the potentiometric surface declined to the south and southeast toward large well fields at Crofton, Severndale, Arnold, Annapolis, Waldorf, LaPlata, Indian Head, and Morgantown. The ground-water levels reached 18 feet below sea level at Crofton, 62 feet below sea level at Severndale, 26 feet below sea level at Arnold, more than 20 feet below sea level near Annapolis, 160 feet below sea level in the Waldorf area, nearly 100 feet below sea level at LaPlata, more than 110 feet below sea level at Indian Head, and 75 feet below sea level at the Morgantown powerplant.

Open-File Report↗
USGS1996

The difference between the potentiometric surfaces of the Aquia aquifer of September 1982 and September 1995 in southern Maryland

A map showing the net change in the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in southern Maryland was based on water levels measured in 66 wells from September 1982 to September 1995 and shows that the decline of the potentiometric surface during the 13-year period was 20 to 30 feet in most of the area. The decline was more than 50 feet in the Lexington Park area and more than 60 feet at Solomons Island.

Maryland↗
USGS1996

The difference between the potentiometric surfaces of the Magothy Aquifer of September 1975 and September 1995 in southern Maryland

A map showing the net change in the poentiometric surface of the Magothy aquifer in the Magothy Formation of Cretaceous age in southern Maryland from September 1975 to September 1995 was based on water-level measurements in 67 wells. The map shows that the decline of the potentiometric surface during the 20-year period ranged from 2 to 21 feet in the northernmost part of the study area. The decline was greater than 40 feet in parts of southern Prince Georges County, 75 feet at Waldorf, and 28 feet at the Chalk Point powerplant.

Maryland↗
USGS1995

Potentiometric surface of the Aquia Aquifer in southern Maryland, September 1994

A map showing the potentiometric surface of the Aquia aquifer in the Aquia aquifer in the Aquia Formation of Paleocene age in southern Maryland during September 1994 was prepared from water levels measured in 74 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 131 feet below sea level in one well near the center of the cone.

Open-File Report↗
USGS1995

Potentiometric surface of the Magothy Aquifer in southern Maryland, September 1994

A map showing the potentiometric surface of the Magothy aquifer in the Magothy Formation of Cretaceous age in southern Maryland during September 1994 was prepared from water levels measured in 85 wells. The potentiometric surface was highest near the northwestern boundary and outcrop area of the aquifer in topographically high areas of Anne Arundel and Prince Georges Counties. Regionally, the potentiometric surface sloped gently downward toward 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 centered around well fields in the Annapolis, Waldorf, and Chalk Point areas. Ground-water levels were as low as 60 feet below sea level in the Waldorf area, more than 45 feet below sea level at Chalk Point, and almost 15 feet below sea level near Annapolis.

Open-File Report↗
USGS1995

Potentiometric surface of the upper Patapsco Aquifer in southern Maryland, September 1994

A map showing the potentiometric surface of the upper Patapsco aquifer in the Patapsco Formation of Cretaceous age in southern Maryland during September 1994 was prepared from water levels measured in 43 wells. The potentiometric surface was at least 70 feet above sea level near the northwestern boundary and outcrop area of the aquifer in a topographically high area of Anne Arundel County, and nearly 60 feet above sea level in a similar setting in Prince Georges County. From these high areas, the potentiometric surface declined to the south and southeast toward large well fields in the Annapolis and Waldorf areas and at the Chalk Point powerplant. Ground-water levels reached nearly 30 feet below sea level in the Annapolis area, nearly 110 feet below sea level southwest of Waldorf, and more than 25 feet below sea level at the Chalk Point powerplant.

Open-File Report↗
USGS1995

Potentiometric surface of the lower Patapsco Aquifer in southern Maryland, September 1994

A map showing the potentiometric surface of the lower Patapsco aquifer in the Patapsco Formation of Cretaceous age in southern Maryland during September 1994 was prepared from water levels measured in 56 wells. The potentiometric surface was at least 104 feet above sea level near the northwestern boundary and outcrop area of the aquifer in a topographically high area of Prince Georges County, and at least 89 feet above sea level in a similar setting in Anne Arundel County. From these high areas, the potentiometric surface declined to the south and southeast toward large well fields at Crofton, Severndle, Arnold, Annapolis, Waldorf, La Plata, Indian Head, and Morgantown. The ground-water levels reached 20 feet below sea level at Crofton, 80 feet below sea level at Severndale, 25 feet below sea level at Arnold, more than 10 feet below sea level near Annapolis, more than 130 feet below sea level in the Waldorf area, more than 100 feet below sea level at La Plata an Indian Head, an nearly 80 feet below sea level at the Morgantown powerplant.

Open-File Report↗
USGS1993

Potentiometric surface of the Aquia Aquifer in southern Maryland, September 1991

A map showing the potentiometric surface of the Aquia aquifer in the Aquia Formation of Paleocene age in southern Maryland during September 1991 was prepared from water levels measured in 82 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. Groundwater levels were more than 60 feet below sea level in a 60-sq-mi area surrounding the deepest part of the cone of depression and 117 feet below sea level in one well near the center of the cone.

Open-File Report↗