Borehole-geophysical characterization of a fractured-bedrock aquifer, Rye, New Hampshire
Borehole geophysical logs collected from six wells were analyzed to characterize a high-yield bedrock aquifer in the Town of Rye, New Hampshire. Video camera, caliper, fluid temperature and conductivity, natural gamma, and deviation logs were used to identify and characterize the fractured bedrock. More advanced geophysical tools included acoustic televiewer and borehole radar, which were used to determine the orientation of fractures and fracture zones that intersect and surround each of the six wells. Borehole-radar surveys included single-hole directional-reflection surveys. The borehole radar logs indicate that the bedrock aquifer is highly fractured. Zones of low velocity and high attenuation in the radar logs correlated with the fractures and fracture zones observed in the standard geophysical logs of the six wells. The strikes of the fracture sets, as determined by the acoustic televiewer, coincide with photolineaments identified on high-altitude and low-altitude aerial photography and side-looking airborne radar (SLAR). The coincident fracture sets and lineaments trend N100°E, N140°E, N170°E, and N40°E.
Citation Information
Publication Year | 1999 |
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Title | Borehole-geophysical characterization of a fractured-bedrock aquifer, Rye, New Hampshire |
DOI | 10.3133/ofr98558 |
Authors | C. D. Johnson, A.H. Dunstan, Thomas J. Mack, J.W. Lane |
Publication Type | Report |
Publication Subtype | USGS Numbered Series |
Series Title | Open-File Report |
Series Number | 98-558 |
Index ID | ofr98558 |
Record Source | USGS Publications Warehouse |
USGS Organization | Office of Ground Water |