Mount Sopris Instruments has been working with GeoSpec Drilling on a variety of groundwater projects throughout the state of Nebraska. In order to supplement their investigation, GeoSpec rented the new 60mm Borehole Nuclear Magnetic Resonance (NMR or BMR) system.
The NMR rental system included:
- Nuclear Magnetic Resonance tool (60mm, 2.36 inch diameter)
- OPAL Acquisition Logger
- 4MXB winch, spooled with 480 meters of standard 3/16 inch 4-conductor geophysical wireline
- WellCAD display/processing software
- Accessory Kit (sheave wheel, centralizers, spares…)
BMR is an advanced geophysical logging tool available for rent from Mount Sopris. This tool provides an accurate characterization of pore structure in the subsurface by measuring signals from magnetic resonance. This measurement can distinguish fluid types, and determine rock porosity, fluid content and permeability. At the Nebraska sites real time total porosity, specific yield and specific retention were all measured directly in-situ. Since the tool is specifically tuned to sense the fluid-filled pores only, measurement accuracy is completely unaffected by matrix composition.
No special calibrations to formation lithology are therefore required. This superior response capability contrasts completely with the lithology-dependent measurement principle of conventional logging tools. Aquifer permeability can also be derived from analysis of NMR responses, and compared to other methods, such as packer and core testing, NMR is cost-effective. See Table below.
Taylor Weber and Jim LoCoco, from Mount Sopris, drove the NMR system out to Nebraska to assist GeoSpec with the operation. The purpose of this log was to identify which water bearing zones would provide the highest production. After logging the probe successfully down and back up the borehole, the data was analyzed in real-time and the well was constructed accordingly.
