Potential Water-Bearing Fractures in New Hampshire Bedrock
Evaluated with Geophysical Methods

Finding high-yielding wells in fractured-bedrock aquifers requires several tools, tests, and information to help in the search. The U.S. Geological Survey, in cooperation with the New Hampshire Department of Environmental Services, has released a report describing the results of tests of several geophysical survey methods to test these tools at several wells in southern New Hampshire.

"Geophysical survey results can be used to indicate the location and orientation of fracture zones, through which ground water may flow in crystalline rock," said Jim Degnan, Hydrogeologist and author of the report. Until now, few studies have been published to document the effectiveness of geophysical tools for investigating a fractured crystalline bedrock aquifer, especially in the Northeast. The results of this USGS study show that some of the tools could locate areas associated with bedrock fractures at high-yielding well sites. These tools work best when results are examined along with geologic information and other data such as drillers' well records.

The study results are published in Water-Resources Investigations Report 01-4183, titled "Geophysical investigations of well fields to characterize fractured-bedrock aquifers in southern New Hampshire," by James R. Degnan and others, and is available for viewing at the USGS office in Pembroke, N.H. by contacting the Outreach Coordinator at (603) 226-7837. A paper copy can be ordered at cost by calling the toll-free number 1-888-ASK-USGS.

As the nation's largest water, earth and biological science and civilian mapping agency, the USGS works in cooperation with more than 2,000 organizations across the country to provide reliable, impartial, scientific information to resource managers, planners, and other customers. This information is gathered in every state by USGS scientists to minimize the loss of life and property from natural disasters, contribute to the sound conservation, economic and physical development of the nation's natural resources, and enhance the quality of life by monitoring water, biological, energy, and mineral resources.

* * * USGS * * *

New Hampshire/Vermont District
U.S. Department of the Interior 361 Commerce Way
U.S. Geological Survey Pembroke, NH 03275

Contact:

General: Debra Foster
Phone: (603) 226-7837
Fax: (603) 226-7894
Email: dhfoster@usgs.gov

Technical: Jim Degnan
Phone: (603) 226-7826
Email: jrdegnan@usgs.gov

Editors Note:

In-depth information about USGS programs may be found on the USGS home page: http://www.usgs.gov or http://water.usgs.gov.

For information on New Hampshire programs, http://nh.water.usgs.gov