Thursday, December 6, 2007 : 1:05 p.m.
Borehole Geophysics I: Nuclear, Electric, and Electromagnetic
1) Nuclear – gamma, neutron, and gamma-gamma
2) Electric – spontaneous potential, single-point resistance, and normal resistivity
3) Electromagnetic – induction conductivity and magnetic susceptibility
The principles, instrumentation, and data collection and analysis of these geophysical logs will be presented. Applications for lithostratigraphic correlation, aquifer and confining unit characterization, and saltwater-intrusion delineation will be discussed.
John H. Williams, USGS John H. Williams has a MS in Geology from Penn State University and currently is the Ground-Water Specialist for the U. S. Geological Survey Water Science Center in New York. He is an integral part of a Survey-wide training and technology transfer program in borehole geophysics. John also has provided technical assistance to the U. S. Environmental Protection Agency, Army Corp of Engineers, Nuclear Regulatory Commission, and State cooperators on borehole-geophysical applications in a wide range of ground-water investigations in fractured bedrock.