Share

First State Geology Newsletter Signup

First State Geology has been the newsletter of DGS for over 25 years.

Click here to signup!

Site content related to keyword: "aquifer"

HM2 Geohydrology of the Newark Area, Delaware

Geohydrology of the Newark Area, Delaware

Geology and Hydrology of the Newark, Delaware area. There are 2 sheets in this series.

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

RI13 The Occurrence of Saline Ground Water in Delaware Aquifers

The location of the fresh-salt-water-boundary in the deeper aquifers of Delaware is related mainly to head values. Near coastal areas, dynamic conditions may prevail that affect the interface position within shallow aquifers open to the sea. Holocene and Columbia sands which form Delaware's shallow water-table aquifers contain brackish water in scattered coastal areas while brackish water in the artesian aquifers is found at various depths. Water from Chesapeake Group sediments (Miocene) is fresh in Kent County but is salty in poorly defined areas of Sussex County. The interface in the Piney Point Formation (Eocene) lies just north of Milford and extends in a northeast-southwesterly direction across the State. Brackish water exists in the Magothy and Potomac formations of Cretaceous age a few miles south of Middletown. Heavy pumping near sources of brackish water should be avoided for the present. Proper location of monitoring wells is necessary for detection of future chloride movement.

RI10 Pleistocene Channels of New Castle County, Delaware

RI10 Pleistocene Channels of New Castle County, Delaware

Two Pleistocene channel-systems are recognized in New Castle County, (1) a system of straight channels located in the area north of the Chesapeake and Delaware Canal and (2) a braided system occupying the area south of the Canal.

Fluctuations of the flow regime of Pleistocene streams were frequent as evidenced by sedimentary structures and widespread distribution of gravels in the channel deposits.
During high stream flows most of the study area was submerged, while during low flows large interstream areas and islands emerged.

The transporting agents of the Pleistocene sediments were primarily melt-water streams originating below glaciers which at times advanced to within 100 miles north of New Castle County. Thus, the age of the deposits is thought to be glacial, but there is no indication as to which glacial stage they belong. However, the channels appear to have been formed contemporaneously by a major distributary system.

RI4 Possibilities for the Storage of Natural Gas in Delaware

RI4 Possibilities for the Storage of Natural Gas in Delaware

Considerable quantities of natural gas are used in Delaware; however, there are no facilities for the storage of large quantities of gas within the state. All the gas is "piped in" and distributed by the local public utility companies. These companies are interested in the possibilities for the underground storage of natural gas, but there are no obvious underground reservoirs such as depleted oil or gas fields.

RI3 Wells for the Observation of Chloride and Water Levels in Aquifers that Cross the Chesapeake and Delaware Canal

RI3 Wells for the Observation of Chloride and Water Levels in Aquifers that Cross the Chesapeake and Delaware Canal

Three test wells were drilled near the banks of the Chesapeake and Delaware Canal, in aquifers formed by sand beds in two geologic units, the nonmarine Cretaceous sediments and the Magothy formation, which crop out along the sides and across the bottom of the canal. The canal carries tidal flow from the Delaware River to and from Chesapeake Bay. The purpose of the wells was to determine whether salt water from the canal has entered the water-bearing beds of these formations, and to determine the head of water in them. It was found that the sands contain fresh water, uncontaminated, and that apparently there was discharge of fresh water from the aquifers to the canal under low head, at least from the winter of late 1955 through early autumn 1957.

RI2 High-Capacity Test Well Developed at the Air Force Base, Dover, Delaware

RI2 High-Capacity Test Well Developed at the Air Force Base, Dover, Delaware

A thick aquifer of Eocene age underlies the Dover area, Delaware at depths ranging from 250 to 400 feet below the land surface. The aquifer is about 250 feet thick beneath the Dover Air Force Base and is composed of fairly uniform medium to fine glauconitic quartz sand. The static water level in a test well at the base was 18 feet below the land surface, or 5.7 feet above sea level, on April 17, 1957. The yield of the test well was about 300 gpm (gallons per minute), and the specific capacity at the end of a 12-hour pumping period was 8.3 gpm per foot of drawdown.

RI1 Salinity of the Delaware Estuary

RI1 Salinity of the Delaware Estuary

The purpose of this investigation was to obtain data on and study the factors affecting the salinity of the Delaware River from Philadelphia, Pennsylvania to Reedy Island, Delaware. The techniques of analyses of data and results of the analyses are presented.

DGS issues report on groundwater discharge areas

RI74 Locating Ground-Water Discharge Areas In Rehoboth And Indian River Bays And Indian River, Delaware Using Landsat 7 Imagery

The Delaware Geological Survey (DGS) at the University of Delaware has released a new technical report that identifies locations of groundwater discharge to estuaries and determines locations of discharge into the Inland Bays.