Geophysical well logging provides valuable information about rock and soil properties adjacent to wells. Multiple logs measuring different material properties are used to define material types adjacent to the well. Information collected in many wells is used to extrapolate geology throughout a site. Often particular formations yield log curves with distinctive patterns making it possible to correlate specific lithologic units between wells. Geophysical well logging defines:
Borehole television verifies the integrity and construction of existing ground water supply and monitoring wells. The borehole camera provides sharp images of actual downhole conditions. Video tapes are made for permanent records. Borehole video visually inspects and locates:
Borehole seismic surveys measure geologic boundaries and rock velocities in the vicinity of boreholes. They are most commonly used to measure various types of rock moduli in situ. P and S-waves are transmitted from the source on the surface to receivers in an adjacent borehole (downhole) or from a source located in one borehole to receivers located in another (crosshole). Borehole seismic surveys provide information about:
Seismic tomography is applied to situations where detailed pictures of the subsurface are needed. Tomography utilizes both borehole to surface and borehole to borehole shooting. Sophisticated computer programs invert the field data into a tomographic image showing a very accurate two dimensional diagram of the velocity structure in the surveyed areas. Tomography is employed to detect or map:
At J R Associates we stand ready to apply our geophysical expertise to your particular requirements. Please contact us to discuss how our combination of techniques, knowledge, and experience can provide you with a window on what's underground.
Ph: (408) 293-7390 EMail: jra@GreatGeophysics.com